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Universit Louis Pasteur, Institut Le Bel, 4, rue Blaise Pascal, 67000 Strasbourg, France, e-mail: hosseini@chimie.u-strasbg.fr Supramolecular synthesis, a construction approach based on the use of reversible interactions, is a domain of current interest. This strategy, by combining molecules through non-covalent interac tions, allows to build up complex supramolecular architectures and offers endless possibilities. Self assembly is a process generating supramolecular entities from molecular components capable of mutual interactions. The combination of supramolecular synthesis with self-assembly processes leads to a powerful strategy allowing the generation of structural and functional complexity. Some 15 years ago, we entered a domain called molecular tectonics which deals with the design and for mation of molecular networks in the crystalline phase. This approach combines supramolecular syn thesis and self-assembly in the solid state. After a general and conceptual introduction of the field, variety of tectons (construction units) and molecular networks will be described.

From Tectons to Molecular Networks y y x x z z 2x2 4x4 4x N C T1T2 A F1F2 A Tectons y x N T1T2 A z Acknowledgements: Many thanks to the Universit Louis Pasteur, Institut Universitaire de France, CNRS and the Ministry of Education and Research for financial support References 1. M. W. Hosseini, Acc. Chem. Res., 2005, 38, 313.

2. M. W. Hosseini, Chem. Comm., Focus Article, 2005,582.

3. M. W. Hosseini, Cryts. Eng. Comm., 2004, 6, 4. M. W. Hosseini, Coord.Chem. Rev., 2003, 240, 157.

5. M. W. Hosseini, A. De cian, Feature Article in J. C. S. Chem. Comm. 1998, 727.


Universit Bordeaux 1 CNRS UMR 5248, Insitut Europen de Chimie et Biologie, 2 rue Robert Escarpit, 33607 Pessac, France, Huc I.cb.u-bordeaux.fr The amazing variety of structures and of functions displayed by proteins is attainable with a set of only about 20 amino-acid constituents arranged in a linear sequence. One can only wonder what structures and what functions are attainable by appropriately combining the innumerable non natural monomers available to chemists. To answer this question, synthetic foldamers oligomers that fold into well-defined conformations in solution have been the object of great attention and very active research over the past ten years. It has been shown that the secondary structural motifs of proteins are not restricted to the -peptide backbone but belong to many classes of oligomers as, for example, the numerous molecular strands reported to wind into helices. Among the most studied families of non-natural oligomers are aliphatic,, and -peptides, which bear particular signifi cance because of their similarity to -peptides.

This lecture will focus on the promising family of aromatic oligoamide foldamers which feature a remarkable combination of structure predictability, stability, tunability and ease of synthesis, and thus possess a high potential for mimicking the secondary structures of biopolymers. Several sec ondary helical motifs can in turn be covalently associated to produce very large (8 KD), structur ally well-defined, folded architectures which compare in size and complexity with small proteins.

The aryl-amide bond rotation can be restricted through specific attractive and repulsive interac tions between amide and functional groups at the ortho position on the aryl moiety. The overall con formation of an oligomer thus results from the simple linear combination of the local conforma tional preferences at each amide bond. Thus, by simply changing the relative orientation of the acid and amine units, and by tuning the size of these units, the curvature of the oligomeric strand may be adjusted from strictly linear to highly bent, giving rise to helices of controllable diameter and to ex tended linear conformations. The folded states of these oligomers also give rise to large conforma tional changes and dynamic phenomena. For example, helixlinear strand transitions may be in duced upon changing the local conformational preference of aryl-amide bonds using protonation of endocyclic pyridine nitrogen atoms or metal ion coordination. Helical handedness may be induced in solution by chiral groups at the end of a helix, and reversibly switched off in the solid state. Ex tension of the single helices like springs allow their hybridization into double helices.

References 1. Hecht, I. Huc (Eds), Foldamers: Structure, Properties, and Applications, 2007, Wyley-VCH, Weinheim, ISBN 13: 978-3-527-31563-5.

2. N. Delsuc, J.-M. Lger, S. Massip, I. Huc Angew. Chem. Int. Ed. 2007, 46, 214.

3. D. Haldar, H. Jiang, J.-M. Lger, I. Huc Angew. Chem. Int. Ed. 2006, 45, 5483.

4. C. Zhan, J.-M. Lger, I. Huc, Angew. Chem. Int. Ed. 2006, 45, 4625.

5. C. Dolain, J.-M. Lger, N. Delsuc, H. Gornitzka, I. Huc Proc. Natl. Acad. Sci. (USA) 2005, 102, 16146.

6. C. Dolain, H. Jiang, J.-M. Lger, P. Guionneau, I. Huc J. Am. Chem. Soc. 2005, 127, 12943.

7. C. Dolain, A. Grlard, M. Laguerre, H. Jiang, V. Maurizot, I. Huc, Chem. Eur. J. 2005, 11, 6135.

8. J. Garric, J.-M. Lger, I. Huc Ang. Chem. Int. Ed. 2005, 44, 1954.

9. C. Dolain, C. Zhan, J.-M. Lger, L. Daniels, I. Huc, J. Am. Chem. Soc. 2005, 127, 2400.

10. V. Maurizot, C. Dolain, Y. Leydet, J.-M. Lger, P. Guionneau, I. Huc J. Am. Chem. Soc. 2004, 126, 10049.

11. H. Jiang, C. Dolain, J.-M. Lger, H. Gornitzka, I. Huc J. Am. Chem. Soc. 2004, 126, 1034.

VIII , , 2007 FINELY DISPERSED FERROMAGNETIC SYSTEMS BASED ON LAYERED DOUBLE HYDROXIDES AND NANOPARTICLES OF FERROMAGNETIC METALS Isupov V.P.a, Mitrofanova R.P.a, Chupakhina L.E.a, Boldyrev V.V.a, Starikova E.V.a, Abornev I.S.b, Martyanov O.N.b, Yudanov V.F.b a Institute of Solid State Chemistry and Mechanochemistry SB RAS, Kutateladze str., 18, Novosibirsk, b Institute of Catalysis SB RAS, Lavrentiev av., 5, Novosibirsk, Finely dispersed systems composed of micron or submicron sized ferromagnetics coated with a bio logically compatible material, the surface of which is modified by functional groups, attract atten tion as the magnetic drug carriers1. The capacity of these carriers is not high, so it seems interesting to develop ferromagnetic systems in which the molecules of drugs would be present not only on the surface of the material but also in the bulk, which would allow one to achieve a substantial increase in the capacity of these carriers. In order to make the systems of this kind, it is possible to use inter calation compounds with layered structure, including layered double hydroxides (LDH), as a carrier of medical substances2,3. In the present work we consider the possibility to synthesize these carriers on the basis of Li-Al LDH and nanoparticles of ferromagnetic metals (Ni, Co). The proposed method involves the following stages: synthesis of Li-Al LDH intercalated with metal complexes [Medta]2- (M Co, Ni);

their thermal decomposition with the formation of nickel (cobalt) nanopar ticles distributed over the carbon-containing X-ray amorphous matrix of lithium aluminates;

the formation of a composite Li-Al DLH/metal nanoparticles in the interaction of thermolysis products with aqueous solutions of lithium salts. The processes of synthesis of the initial precursors and their thermal decomposition were thoroughly investigated previously4,5. Using XRD and FMR in situ we investigated the formation of ferromagnetic carriers based on Li-Al LDH and nanoparticles of fer romagnetic metals. The effect of the conditions of thermal decomposition of precursors and the ef fect of the parameters hydrochemical action (concentrations of lithium salts, time of interaction, process temperature) on the phase and chemical composition of the formed ferromagnetic systems was investigated.

The investigation was supported by RFBR under Project No. 06-03-32107, by the RAS Presidium Program (Project No. 8.16), Project 5.7.3 of the Department of Chemistry and Materials Science Chemistry and physicochemistry of supramolecular systems and atom clusters, by the Leading Scientific Schools program (Project No. NSh-4505.2006.3), and by CRDF under Project RUX0-008-NO-06.

References 1. P. Tartaj, M.P. Morales, T. Gonsalez-Carreno, S. Veintemillas-Verdaguer, J. Magn. and Magn.

Materials 2005, 290-291, 2. V.P. Isupov, R.P. Mitrofanova, L.E. Chupakhina, Abstracts of the Xth International seminar on inclusion compounds (ISIC-10), Kazan, 2005, 3. Hui Zhang, Kang Zou, Hui Sun, Xue Duan, Journal of Solid State Chemistry 2005, 178, N11, 4. V.P. Isupov, L.E. Chupakhina, R.P. Mitrofanova, et al., Solid State Ionics 1997, 101/103, 5. V.P. Isupov, K.A. Tarasov, L.E. Chupakhina, et al. Dokl. Chem 2003, 391, nos. 4-6, 2240 VIII , , BINDING SITE OF CRUCIAL SUBDOMAINS IIID/E OF HEPATITIS C IRES ON THE HUMAN 40S RIBOSOMAL SUBUNIT Karpova G.G.a, Laletina E.S.a, Graifer D.M.a, Malygin A.A.a, Shatsky I.N.b a Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia b Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, 119899, Russia Cap-independent pathway of "internal initiation" of translation is based on recruitment of the so called internal ribosomal entry site (IRES), a specifically structured RNA segment in the 5 untranslated region upstream the initiation AUG codon. The genomic RNA of hepatitis C virus (HCV), one of the most dangerous human pathogens, contains an IRES element able to form a sta ble binary complex with the 40S ribosomal subunit providing the positioning of the initiation AUG codon at the P site without any initiation factors. To study the role of the respective IRES sequences in the binding to 40S subunits, we elaborated an approach based on application of derivatives of oligodeoxyribonucleotides complementary to specific sequences of the HCV IRES and bearing an alkylating group at the terminal 3'- or 5'-phosphate to obtain covalent adducts of the IRES with the deoxy oligomers. The purified adducts have been then used for testing their binding properties. It was found that affinity of 40S subunits for the HCV IRES covalent adducts bearing deoxy oli gomers complementary to sequences in hairpins IIId and IIIe was drastically lower than that for the unmodified IRES. This indicated that HCV IRES subdomains IIId and IIIe are the main determi nants for binding to 40S subunits. To introduce photoactivatable group into subdomain IIIe or IIId, phosphoramide bond in the respective covalent adduct was hydrolysed under mild acidic condi tions, and aryl azide group was selectively introduced at the benzylamine group liberated after hy drolysis1. Mild UV-irradiation resulted in cross-linking of the HCV IRES derivatives to the 40S subunit;

targets for cross-linking were proteins rather than rRNA. Analysis of the cross-linked pro teins revealed that photoactivated group in hairpin IIIe modified proteins S5 and S16 and to a lesser degree p40 and S3a.2 The same group in hairpin IIId cross-linked to protein S14 and to a smaller extent to S3a. Notably, none of these proteins was found earlier to cross-link to mRNA analogues bearing the same photoactivatable group. Hence, binding site of HCV IRES on the 40S subunit al most does not overlap with the binding site for cellular mRNAs. Comparison of the results obtained with data of cryo-electron microscopy made it possible to draw a conclusion on location of HCV IRES binding on the 40S subunit surface.

The work was supported by Russian Foundation for Basic Research (grant #05-04-48357-a).

References 1. E.S. Laletina, D.M. Graifer, A.A. Malygin, I.N. Shatsky, G.G. Karpova, Rus. J. Bioorg. Chem. 2006, 32, 280.

2. E. Laletina, D. Graifer, A. Malygin, A. Ivanov, I. Shatsky, G. Karpova, Nucleic Acids Res. 2006, 34, 2027.

VIII , , 2007 OLIGOPYRROLE BASED ARTIFICIAL RECEPTORS FOR OXOANIONS Katayev E.A.a, Boev N.V.a, Mishkovskaya E.N.a, Kolesnikov G.V.a, Sessler J.L.b, Tananaev I.G.c, Ustynyuk Yu.A.d a A.N.Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova st. 28, 119991, Moscow, Russian Federation.

E-mail: katayev@ineos.ac.ru b Department of Chemistry & Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165 USA c Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of Science, Leninskiy pr. 31, 119991, Moscow, Russian Federation d Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskie gori, 1/3, 119992, Moscow, Russian Federation The development of highly efficient systems capable of binding specific anions selectively is rec ognized as being a key predicate to solving a number of fundamental problems, including anion sensing, extraction, and separation. Oxoanions are of particular relevance in this regard.1 Carboxy late anions are important constituents of aminoacids and proteins. Likewise, phosphates and phos phate esters are ubiquitous in biology, playing roles in signaling, energy transduction, information storage and expression. A number oxoanions such as sulfate, pertechnetate and phosphate are also recognized as toxic or undesirable in certain situations. Hybrid ligands containing binding motifs of different types represent a promising class of compounds for the highly selective binding of oxoan ions. Since oxoanions can exist in solution in protonated forms we have suggested that the receptor molecules in question should contain both hydrogen bond acceptor and hydrogen donor binding motifs.2 Modulation of their number, as well as the conformation of the ligand is expected to impart high selectivity towards a particular target anion. In our work to date we have used anion-controlled (supramolecular) synthesis to prepare the receptors from appropriately chosen dialdehyde and dia mine building blocks, including ones containing polypyrrole and amido subunits. Imine bonds, functionality that can accept a proton from protonated oxoanions, were then used to link these groups into macrocycles. According to our investigations, the best receptor for a target anion is am plified during the condensation of building blocks. Several macrocyclic systems have been con structed using this anion-controlled approach to synthesis, several of which display high affinity for the hydrogensulfate, dihydrogenphosphate, and acetate anions. 2,2-Bipyrrole has also been used as a building block and found to give new receptors for the perrhenate binding.3 The ring expansion of several of our macrocycles has been found to occur under thermodynamic control in the presence of HSO4- and H2PO4- anions in acetonitrile solution. Finally, the anion binding properties and X-ray crystal structures of the [3+3] product arising from the condensation of diformyl bipyrrole and 2,6-dimethylamino(2-aminophenyl)-pyridine revealed strong similarity with the active sites of the natural phosphate and sulfate binding proteins.

Acknowledgements. The work was supported by Russian Foundation for Basic Research (grant no. 05-03- and 05-03-08017) References 1. E. A. Katayev, Y. A. Ustynyuk and J. L. Sessler, Coord. Chem. Rev., 2006, 250, 3004-3037.

2. J. L. Sessler, E. Katayev, G. D. Pantos, P. Scherbakov, M. D. Reshetova, V. N. Khrustalev, V. M. Lynch and Y. A.

Ustynyuk, J. Am. Chem. Soc., 2005, 127, 11442-11446.

3. E. A. Katayev, N. V. Boev, V. N. Khrustalev, Y. A. Ustynyuk, I. G. Tananaev and J. L. Sessler, J. Org. Chem., 2007, 72, 2886-2896.


Department of Structural Biology and Genomics, IGBMC, Illkirch, France The ribosome is a molecular machinery in living cells that catalyses the translation of the genetic code and performs protein biosynthesis. We study the structure-function relationship of the ribo some with transiently binding regulators such as protein factors and messenger RNAs (mRNA).

The functional complexes are studied through a combination of biochemistry, structural biology (including cryo-electron microscopy and crystallography), biophysics and bio-informatics. The presentation will illustrate several reaction intermediates of the ribosomal machinery trapped in presence of associated factors. The role of structured mRNAs in the regulation of protein synthesis initiation will be discussed, which we show is performed through a docking and unfolding of the mRNA on a dedicated site of the ribosome, followed by binding into the mRNA channel inside the ribosome.

VIII , , 2007 PROBING BIOLOGICAL SUPRAMOLECULAR STRUCTURES WITH NEW ENVIRONMENT-SENSITIVE FLUORESCENT DYES Klymchenko A.S., Yushchenko D.A., Jain N., Zhang X., Shvadchak V.V., MBaye G., Oncul S., Didier P., Duportail G., Mly Y.

Photophysique des Interactions Biomolculaires, UMR 7175-LC1 du CNRS, Institut Gilbert Laustriat, Facult de Pharmacie, Universit Louis Pasteur, 67401 Illkirch, France e-mail: aklymchenko@pharma.u-strasbg.fr Fluorescent molecular probes are powerful tools for studying biological self-assembled systems. To design probes with high sensitivity to structural changes of these systems, we used environment sensitive two color fluorophores of the 3-hydroxychromone family1. Moreover, to achieve high af finity of these probes for a particular supramolecular structure, we specially designed their anchor groups. In this respect, to study biomembranes, which are nanostructures self-assembled from lipid molecules, we have developed 3-hydroxychromone dyes bearing long hydrophobic chains and zwit terionic groups. These probes exhibit high affinity to lipid membranes and, being added to living cells, bind selectively the outer leaflet of the plasma membrane. These probes can follow the pro grammed cell death (apoptosis), which results in a change of the lipid composition of the outer membrane leaflet due to fast flip-flop exchange with the inner leaflet2. In addition, the new probes also allow us to study and visualize the clustering of particular lipids within the bilayers, which is known as lipid rafts.

To develop probes highly specific to DNA, we modified a 3-hydroxychromone fluorophore with a group bearing several positive charges. Unlike non-substituted fluorophore, the positively charged derivatives bind strongly DNA molecules, which is observed as a dramatic change in the two-color emission. The obtained fluorescence spectra of the DNA-probe complexes indicate on the low po larity of the fluorophore binding site, which suggests the intercalation of the fluorophore between the nucleic bases of the double helix. Importantly, our DNA probes exhibit strong color change of transition from double strand to single strand forms, so that the new probes are highly promising for studying dynamics of nucleic acid complexes. We also demonstrate that our new lipid membrane and DNA probes can be used to follow interactions between DNA and lipid membranes, which re sults in the formation of the gene delivery nanostructures.

apoptotic cells Fluorescence Intensity 1. Probe Probe 0. Apoptosis 0. normal cells 0. 500 600 Wavelength (nm) Fig. 1. Changes in the transmembrane lipid asymmetry of cell membranes during programmed cell death and the fluorescence response of our probe to these changes.

References 1. A. S. Klymchenko, A. P. Demchenko, Phys. Chem. Chem. Phys. 2003, 5, 461.

2. V. V. Shynkar, A. S. Klymchenko, C. Kunzelmann, G. Duportail, C. D. Muller, A. P. Demchenko, J.-M. Freyssinet, Y. Mely, J. Am. Chem. Soc., 2007, 129, 2187.

2244 VIII , , SMART AND SOFT SUPRAMOLECULAR AGGREGATES IN AQUEOUS SOLUTIONS Konovalov A.I., Zakharova L.Ya., Mustafina A.R., Ibragimova A.R., Elistratova Y.G.

A.E.Arbuzov Institute of Organic and Physical Chemistry, Kazan Research Center of the Russian Academy of Sciences, 8 Acad. Arbuzova Str., 420088 Kazan, Russian Federation The development of supramolecular systems with various practical properties, such as nanoreactors, sensors, switchers, nanotubes, is becoming one of the most priority directions of a modern chemis try. Present report is devoted to the ways of getting of nanosized aggregates in aqueous solutions, which work as nanoreactors, receptors and sensors. Surfactants, polymers, macrocyclic molecules and metal ions are building blocks of such supramolecular systems. The structure and receptor properties of self-assembled amphiphilic calixarenes, as well as of mixed calixarene-surfactant ag gregates will be considered. The inclusion capacity of calixarene-based nanosized aggregates in ma jor extent depends on the supramolecular packing mode of receptor molecules (calixarenes). The nanoaggregates calixarene-Gd(III) ion and calixarene-surfactant will be viewed as sensors.

An approach for the design of effective catalysts by means of step-by-step modification of su pramolecular assemblies by components with their own catalytic or structuring functions has been worked out. The relation between the structure of nanoaggregates and their catalytic effects on hy drolytic cleavage of phosphorus acid esters is shown. Within the frame of this approach nanoreac tors are designed, which represent lanthanum ions immobilized on calixarene, polymer-colloid or liquid crystalline matrix. The catalytic effect of these assemblies can reach more than six orders of magnitudes. A differentiation of contributions of binding the substrate by calixarene and its su pramolecular effect to the summary catalytic action is exemplified by the calixarene surfactant system.

Acknowledgements The work was supported by RFBR (grant N 07-03-00282).


Institute of Organic Chemistry University of Regensburg, D-93040 Regensburg, Germany Metal complexes with open coordination sites have found wide use in molecular recognition. They serve as binding sites in the development of chemosensors, to study metalloenzyme function in bioinorganic chemistry or direct supramolecular self-assembly.1 Binding of metal complexes with open coordination sites to Lewis-basic guest molecules can be very high, even in polar solvents, and the binding specificity of the coordinated metal ion described by the HSAB principle adds another dimension of selectivity (Figure 1). In the presentation basic principles and recent examples are dis cussed.

Figure The combination of reversible coordinative bonds with weaker specific interactions is particular attractive for the construction of functional compounds and materials for the selective recognition of biomolecules. Imprinting of zinc-cyclen complexes in the presence of creatinine gave polymers with micromolar affinity to the analyte from aqueous solution.2 A luminescent probe for dipeptides was obtained from the combination of a copper imidodiacetic complex with a luminescent crown ether moiety (Figure 2). The presence of the dipeptide Lys-His is signalled by an increase in lumi nescence. H N O N H O N OH NH2 Cu O O O O N O O +O O O NH O N O O O O O Figure Restricting peptide conformation is the mission of a zinc-nitrilo-tri-acetate complex functional ized with a peptide -sheet mimic.4 After coordination of the N-terminal His of a peptapeptide, its conformation in solution is restricted by intramolecular interactions.

2246 VIII , , O O H H O H N N N N N O H H O O O H HO NO O O H H Zn N N N O ON O O N N H H HN O O O Figure Another example is the use of amphiphilic zinc-bis cyclen complexes for guided molecular rec ognition at interfaces. Self-assembled into 2D arrays the reversible coordination of the metal com plexes to phosphate and nucleobases allows a cooperative self-assembly of nucleotides. References 1. M. Kruppa, B. Knig, Chem. Rev. 2006, 106, 3520.

2. M. Subat, A. S. Borovik, B. Knig, J. Am. Chem. Soc. 2004, 126, 3185.

3. M. Kruppa, C. Mandl, S. Miltschitzky, B. Knig, J. Am. Chem. Soc. 2005, 127, 3362.

4. M. Kruppa, C. Bonauer, V. Michlov, B. Knig, J. Org. Chem. 2005, 70, 5305. For related examples, see: X. Li, S.

Miltschitzky, A. Grauer, V. Michlov, B. Knig, Tetrahedron 2006, 62, 12191;

H. R. Kalbitzer, M. Spoerner, T. Graf, B. Knig, Biochem. Biophys. Res. Commun. 2005, 334, 709.

5. D. S. Turygin, M. Subat, O. A. Raitman, V. V. Arslanov, B. Knig, M. A. Kalinina, Angew. Chem. 2006, 118, 5466 5470;

Angew. Chem. Int. Ed. 2006, 45, 5340;

D. S. Turygin, M. Subat, O. A. Raitman, S. L. Selector, V. V. Arsla nov, B. Knig, M. A. Kalinina, Langmuir, 2007, 23, 2517.


Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentiev Av., 630090 Novosibirsk, Russia Affinity labeling technique was intensively developed for the last several decades to study complex protein machines. We have applied this technique to study supramolecular ensembles of base exci sion DNA repair (BER) and nucleotide excision repair (NER). Both processes require a finely tuned action of numerous enzymes and protein factors. The intermediate DNAprotein structures ap peared in the course of DNA repair are too complicated and very dynamic to be studied by X-ray analysis or other instrumental techniques. Photoaffinity labeling has been applied to study assembly of base excision DNA repair machines around DNA. The main idea of our approach consists in in troduction of photoreactive moieties in the course of DNA transactions by the activity of DNA po lymerases. Wide range of photoreactive base-substituted derivatives of dNTPs has been synthesized and used to design photoreactive intermediates of DNA repair either in systems reconstituted of pu rified proteins or in nuclear or cellular extracts of mammalian cells. Photoreactive branch point in termediates of BER have been used in cellular and nuclear extracts to identify composition of pro tein ensembles interacting with damaged DNA and with the BER pathway intermediates. The main target proteins covalently linked to photoreactive branch point BER intermediate formed in mouse embryonic fibroblast cellular extracts were identified by immunoprecipitation assay or by MALDI MS as poly(ADP-ribose) polymerase1 (PARP1), flap endonuclease1 (FEN1), DNA polymerase (Pol), apurinic/apyrimidinic endonuclease1 (APE1) and the high mobility group box 1 protein (HMGB1). Crosslinking experiments combined to functional assay revealed that PARP1 and APE can discriminate DNA intermediates of short-patch and long-patch BER pathways to regulate the process. Chemically reactive DNA structures containing apurinic/apyrimidinic (AP) site were used for proteomic analysis of protein targets in mammalian cellular extracts. PARP1, XRCC1 and Ku70/80 were found to interact with AP-site containing DNA structures. Nucleotide excision repair process was intensively studied using DNA probes carrying synthetic photoreactive DNA damages.

It was shown that bulky photoreactive nucleotide analogs introduced into DNA are the targets for NER system. DNA constructs containing photoreactive damages were used as photoreactive inter mediates of NER to analyze loading of NER factors on damaged DNA. Photocrosslinking of NER factors: XPC-hHR23B, XPA, RPA to photoreactive NER damages were performed using 60-mer DNA duplexes containing matched or mismatched base pairs opposite to damages. All NER pro teins under assay were crosslinked with mismatch structures more efficiently than to photoreactive nucleotide paired with complementing one. Subunits of NER proteins crosslinkined to photoreac tive damaged DNA were identified. Our data show interaction of large subunit of XPC-hHR23B dimer with photoreactive damage. Therefore affinity labeling technique combined to functional as say is a powerful tool to explore supramolecular ensembles of DNA repair and to identify func tional composition of these machines.

This research was supported by RFBR, grants no. 05-04-48319, 07-04-00178, by grant from HFSP RGP0007/ and by grant from INTAS-SBRAS n. 9210.


Institute of Chemistry Far Eastern Branch of the Russian Academy of Science, Vladivostok The interesting results concerning the correlation between the molecular design as well as lumines cent, thermoluminescent, triboluminescent, size-dependent luminescent, reversible thermochromic and luminescent-thermochromic properties in p- element (boron, antimony (III), tellurium (IV)) and lanthanide complexes were obtained by the luminescent, fluorescent electronic microscopy, diffuse reflection spectroscopy methods and low-temperature X-ray analysis.

Correlation between thermo chromic properties of hexabromotellurate (IV) (guanidinium (+1) and (N, N diphenylguanidinium (+1)) and peculiarities of the ligands thermal vibrations were revealed: anomalous strong increase (but not decrease) of the deviation angle 3 of the thermal atomic vibration ellipsoid axis from the metal-ligand bond direction occurs with the temperature lowering. The thermochromic mechanism was interpreted in the frame of Jahn-Teller theory: orbital degeneracy removal of the first excited state of s2ion takes place under increasing the temperature that leads to the increase of Jahn-Teller splitting of long-wave absorption (reflectance) band. Size- dependent luminescent properties of some chelates of boron difluoride were detected for the first time: the luminescence color changes under transfer from bulk crystals to microcrystals. The characteristic peculiarity of microcrystal morphology is the existence of oval nanoparticals of 100 10 nm on the microcrystal face. The ex istence of luminescent thermochromism and reversible photo-induced luminescence color change (blue green) were detected to be characteristic of microcrystals of dibenzoylmethanate of boron difluoride. In the frame of exciton mechanism, the model describing size-dependent processes of excimer and interdimer fluorescence enhancement was suggested. The results obtained correct the literature data concerning the nature of size- dependent luminescence, reversible photo-induced transformations, thermochromism and luminescent thermochromism and need further spectral and structural investigations.


CONSTRUCTING AND STRUCTURAL-FUNCTIONAL INVESTIGATIONS Pozmogova G.E.ab, Chuvilin A.N.a a FGU Research Institute of Physico-Chemical Medicine of Roszdrav.

Malaya Pirogovskaya 1a, Moscow, Russia b Center of Bioengineering of Russian Academy of Sciences.

60-letiya Oktyabrya prosp., 7a, Moscow, Russia A new approach was proposed on constructing of proteins able to associate spontaneously with oligo/polynucleotides, giving transfer complexes. For design of new targeted gene therapy drugs a number of recombinant proteins was obtained. Associates of lasts with various forms of DNA un derwent selective internalization by target cells, according with mechanism of receptor mediated endocytosis, providing nucleic component delivery to intracellular goals.

The processes of formation of complexes and their structures were studied on examples of oli gonucleotides series and plasmid DNA. They interacted with PGEk, recombinant protein1 which consists of addressing domain, the residue of human epidermal growth factor (EGF), and of oligo cationic sequence of nuclear localization signal motif.

It was shown that plasmid DNA is compactified after complexing with PGEk (AFM microscopy data). Effect of DNA conformation on properties, structure and composition of complexes with PGEk was examined in experiments with various oligonucleotides, in particular with telomeric G quadruplex d(TTAGGG)4 (TMO) and its thio-analog (TMS).

Binding of two firsts PGEk molecules with TMO/TMS occurs according with non-cooperative mechanism, K1TMO = (71)x107 M-1, K1TMS = (30.5) x107 M-1. Subsequent linkage up to 6 PGEk molecules per TMO happens by cooperative mechanism, K2TMO = (41.5)x106 M-1 (method of in trinsic UV-fluorescence quenching).

The analysis of rotational relaxation times of TMO and TMS molecules and of their complexes with PGEk showed high mobility of EGF-residues of complexed PGEk. This fact explains steric accessibility of this ligand to interact with cell EGF-receptors. Moreover, comparison of mitotic ac tivities of PGEk and its DNA complexes proves only one EGF-domain of associate to participate in this process, i. e. the whole nucleoprotein complex to become the unified ligand of target receptor.

An expressed correlation was found between complexes structure and biologic properties. PGEk influence on a process of selective oligonucleotide internalization by tumor cells followed by pref erential translocation into nucleoplasm was investigated. PGEk at found optimum ratio essentially increased antineoplastic effect of TMS, and only in relation to target cells. Biological properties of non-cytotoxic TMO preparations were changed discontinuously as PGEk was added. PGEk/TMO (5:1) complex, as well as PGEk/TMS complexes effectively and selectively suppressed target cells growth.

References 1. Pozmogova G.E. et al. Patent RU 2248983, 2005.

2250 VIII , , COMPOSITE OLIGONUCLEOTIDE PROBES TOOLS FOR DNA DIAGNOSTICS Pyshnyi D.V.a, Pyshnaya I.A.a, Kabilov M.R.a, Lomzov A.A.ab, Vinogradova O.A.a, Dmitrienko E.V.ab, Zarytova V.F.a a Institute of chemical biology and fundamental medicine SB RAS, Novosibirsk, Russia b Novosibirsk State University, Novosibirsk, Russia Hybridization of composite oligonucleotide probes (oligonucleotide tandems, bridged oligonucleo tides) with DNA was systematically studied. The perspectives of composite oligonucleotides to be used as probes for highly selective recognition of complementary DNA are shown. Various tech niques were used for the physico-chemical description of duplex formation by these types of oli gonucleotides. The database containing large set of thermodynamic parameters of DNA duplex formation with native and composite oligonucleotide was created. The influence of the ionic strength on the stability of duplexes was char COMPLEXES OF COMPOSITE OLIGONUCLEOTIDES acterized too. As a result the unified thermo BRIDGED TANDEM dynamic parameters which characterize the various types of interaction within the duplex structure were obtained. These data in combi nation with published characteristics1 allow us to design composite oligonucleotide probes nick non-nucleotide insert having desirable hybridization properties with well defined selectivity of binding with DNA.

Substrate properties of DNA complexes of composite oligonucleotides were investigated with the use of DNA-depending enzyme (DNA-polymerase or DNA-ligase). Composite probes were shown to ensure high selectivity of discrimination of single nucleotide substitution in DNA tem plate. On the basis of the data obtained new approaches to analysis of SNP in DNA were proposed and the software for the design optimal oligonucleotide probes for DNA diagnostics tasks was de veloped.

This work was supported by a grant of the MCB Program of RAS (10.6), integration grant of SB RAS (73, 55), grant for young scientist of SB RAS (93), CRDF (BRHE), a grant from the Ministry of Education and Science of the Russian Federation (ZN-454-04), RFBR 06-04-49263.

References 1. J. SantaLucia and D. Hicks, Annu. Rev. Biophys. Biomol. Struc. 2004, 33, 415.



Laboratory of Supramolecular Chemistry and Technology MESA+ Research Institute for Nanotechnology University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands Nanotechnology is a part of the chemical domain, because the ultimate goal is to build nanostruc tures with precision at the molecular level. This requires the ability to manipulate and modify mole cules individually rather than in the bulk. There are many challenges for chemists and in particular for supramolecular chemistry. In our group we are studying several aspects that may contribute to the bottom-up approach to nanostructures. Firstly, molecular printboards will be discussed that can be used to confine molecules in time and space. These printboards are self-assembled monolayers of receptor molecules on flat surfaces. The regular molecular assemblies offer anchoring points for (individual) molecules that can be immobilized (and erased) by supramolecular host-guest interac tions. Suitable printboards are composed of cyclodextrine derivatives, immobilized on gold or glass surfaces. By force-distance spectrocopy we can analyse the forces involved between individual guest molecules and these receptors. Subsequently we can write or print guest molecules like den drimers on these printboards by softlithographic techniques (microcontact printing and dip pen or nano-imprint lithography). We can also use layer-by-layer assembly processes and metal deposition in order to extend 2D-patterns to 3D-objects. By using these assembly processes we are able to fab ricate electronic devices.

References 1. J. Am. Chem. Soc., 2006, 128, 17024- 2. Small, 2006, 2, 1422- 3. Angew. Chem. Int. Ed., 2005, 44, 6282- 4. J. Am. Chem. Soc., 2004, 126, 17050- 2252 VIII , , TRANSITION METAL-COMPLEXED CATENANES, ROTAXANES AND MOLECULAR MACHINES Sauvage J.-P.

Laboratoire de Chimie Organo-Minerale, Universite Louis Pasteur/CNRS, U.M.R.

7177, Institut de Chimie, 4, rue Blaise Pascal, F-67070 Strasbourg-Cedex, France Catenanes represent attractive synthetic challenges in molecular chemistry. The creation of such complex molecules as well as related compounds of the rotaxane family demonstrates that syn thetic chemistry is now powerful enough to tackle problems whose complexity is sometimes remi niscent of biology, although the elaboration of molecular ensembles displaying properties as com plex as biological assemblies is still a long-term challenge.

The field of artificial molecular machines and motors has experienced a spectacular development in the course of the last fifteen years, in relation to biological motors or information storage and processing at the molecular level. A recent example consists of a fast-moving rotaxane whose ring undergoes a pirouetting motion on the millisecond time scale by oxidizing or reducing the central II I copper atom (Cu /Cu ).

Recently, our group has also proposed a transition metal-based strategy for making two dimensional interlocking and threaded arrays. Large cyclic assemblies containing several copper(I) centres could be prepared which open the gate to controlled dynamic two-dimensional systems and membrane-like structures consisting of multiple catenanes and rotaxanes.

In the course of the last three years, we have been much interested in endocyclic but non steri cally hindering chelates. These compounds are based on carefully designed 3,3'-biisoquinoline de rivatives. Some of them have even been incorporated into macrocyclic compounds. A particularly efficient and fast moving molecular "shuttle" based on such a chelate has been made and investi gated as well as three-component molecular entanglements constructed by assembling three such ligands around an octahedral metal centre. These biisoquinoline-based compounds are particularly promising in relation to fast-responding controlled dynamic systems and novel topologies.

VIII , , 2007 STRUCTURE OF LANGMUIR MONOLAYERS AND LANGMUIR-BLODGETT FILMS OF HEMICYANINE Selector S.a, Grauby-Heywang C.b, Abraham E.b, Jonusauskas G.b a Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninsky pr., 31 4, GSP-1, 119991, Moscow, Russia, e-mail: pcss_lab@mail.ru b CPMOH, University Bordeaux 1, CNRS UMR 5798, 351 cours de la Libration, Talence cedex, France Hemicyanine dyes are extensively studied owing to their potential interests in molecular optics or optoelectronics. Their alkyl derivatives are able to form stable Langmuir monolayers and Lang muir-Blodgett (LB) films, but their tendency for aggregation is usually responsible for the forma tion of microheterogeneities in films, limiting potential applications.

In this work, we studied monolayers of 4-[4-(dimethylamino)styryl]-1-docosylpyridium bro mide. At least two different kinds of (-A) isotherms were obtained, showing a plateau characteris tic for a phase transition or a unique phase. In order to precise the necessary experimental condi tions for both cases, different experimental parameters were studied more particularly: subphase temperature and pH (in the 5-40C and 4-10 range, respectively), concentration of the solution, spread volume, time of evaporation (5-60 minutes) and compression speed (5-30 cm2/min).

Monolayers were also prepared by successive spreading of 2 l drop at the air-water interface kept at a constant surface. It was shown that the shape of the unique phase isotherm could be deals with the nucleation of a new phase appearing during spreading.

Even if a complete correlation has not been established, a strong dependence between the sub phase pH and the shape of the isotherm was observed: an increase of subphase pH between 4 and decreases the probability to have an isotherm with a plateau. Moreover the surface pressure range of the plateau increases with pH and mean molecular areas at the beginning of isotherms shifts to lower values. These effects induced by pH could be due to changes of the hemicyanine charge by protonation/deprotonation of its amino-group. At last, in all cases, mean molecular areas are in the same range at high surface pressure.

In order to precise the nature of the observed phase transition, monolayers were also transferred on quartz plates by the Langmuir-Blodgett (LB) method. Fluorescence microscopy, using intrinsic fluorescence properties of hemicyanine dye (maximal excitation at 480 nm, emission above nm), shows the presence of dark irregular domains in a lighter phase. Roughly, their surface density is correlated to the shape of the corresponding (-A) isotherm: in the absence of plateau, the surface density of domains is clearly lower than when the phase transition is observed. At pH 8, filaments surrounding domains are also observed. This effect of pH is not clearly understood at the moment, since the dye pKa is estimated in the 6-7 range. Therefore, LB films were also studied by other complementary methods such as UV-visible absorption, or stationary and time-resolved fluores cence spectroscopy, which give information on the samples at the molecular level. These methods enable us to precise the organization of molecules (presence of aggregates or monomers). This spectroscopic study is presented in a second


(Picosecond time-resolved fluorescence stud ies of hemicyanine Langmuir-Blodgett films, by E. Abraham et al.).

Thus, the existence of two different phase initial states of hemicyanine monolayer has been es tablished. Measurements suggest also that it could be possible to change the organization of hemi cyanine molecules in LB films, by controlling strictly experimental conditions during the spreading of the monolayer at the air-water interface, its compression and its transfer.


Institute of Chemical Biology & Fundamental Medicine.

Lavrentev av. 8, Novosibirsk 630090 Russia.

SELEX (System evolution of Ligands by Exponential enrichment) suggested a decade ago has been successfully put into practice, thus opening fundamentally new possibilities for the development of highly specific and low-toxic drugs.

In the present work we have attempted to develop a molecular meccano that allows ones to ob tain self-assembling molecular ensembles basing on SELEX as well as on well-known selective and highly-efficient organic reactions. Such nanomolecular machines are able to recognize and selec tively bind tumor cells and deliver a necessary agent inside the cells.

In this work we demonstrate the availability of the suggested approach by creating a model self assembling nanomolecular machine that is able to deliver a fluorescent dye into prostate cancer cells.

O O CN O NH Aptamer N N Linker group O Flu O CN O Flu NH Flu Flu Aptamer O O N NH O NN Linker group Flu Flu N NH Flu Flu O Fig. 1. The general approach to synthesis of nanomolecular machines.

This work was supported by RFBR (grant No 07-04-00990-a).



"V.G. Khlopin Radium Institute", St. Petersburg, Russia Calix[4]arenes with dialkyl- and alkylphenyl phosphinoxide substituents at upper rim and calix[5]arene phosphorylated at lower rim show the strong cooperative effect, extracting Eu hun dred times better than monophosphoryl analogs (Fig.).

100 Bu Bu Bu Bu PO PO DEu Bu Bu PO 10 O O 4 O Pr PO Hex Bu Bu O Me Bu Bu O PO PO O O Bu Bu 0,1 PO PO Bu Bu Bu Bu 0, Fig. Extraction of Eu from 0.3 M HNO3 by 0.01M solutions of calixarenes or 0.04 M phosphineox ides in NBTF.

In contrast to monophosphinoxides, the length of alkyl substituent at phosphorus atom in phos phorylated calixarenes strongly affects their extraction properties. In a row of calix[4]arenes with two methylene-diphosphonate substituents at upper rim the extraction efficiency of americium and europium decreases in the following order: propyl isopropyl methyl, ethyl, butyl. The substitu ent value affects the extraction of technetium and palladium only slightly.

Dialkylphosphinoxide (at upper rim) derivatives of calix[4]arene form strong hydrates (shift of (P=O) by 73 cm-1). The hydrates are easily solved in water (up to 300 g/l), but on addition of elec trolyte or elevation of temperature the calixarene is separated into an individual phase, capturing the radionuclides contained in aqueous phase.

The possibility for recovery of radionuclides from HLW was demonstrated by using the extrac tant based on phosphorylated calix[4]arene C67. In three successive contacts about 99,9% of emitters and more than 99,9% of Am and Eu were separated from real HLW.

As to the drawbacks of phosphorylated calixarenes, mention should be made of low rate of emulsions separating into layers in extraction of radionuclides from weakly acidic media.

The work was carried out under financial support of ISTC Project 3405.


R. Agladze Institute of Inorganic Chemistry and Electrochemistry Mindeli str. 11, 0186, Tbilisi, Georgia lpc@geo.net.ge By the example of the interaction between the compounds of chlorides, thiocyanates, nitrates, for mates and acetates with methylpyridine-, nicotine-, isonicotinamides, orto-, meta-, para aminopyridines, 2,3,4,5,6-methylderivatives of ortoaminopyridine in nonaqueous solvents the fol lowing has been established: 1) at the synthesis of given coordination compounds (ratio of the com ponents metal: amine or amide = 1:2 and 1:4) the compound of 1:2 and 1:4 composition is formed.

By data of x-ray crystallographic analysis and IRspectroscopy these ligands are monodentant and are coordinated with metals through nitrogen atoms of heterocycle;

2) at the interaction of methylpyridine-, nicotine-, isonicotine hydrazides and hydrazones of benz-, parapyridine-, di methylaminobenzaldehydes with these complexes in nonaqueous solvents at the ratio synthe sized complex: hydrazide or hydrazone = 1:1 or 1:2, a single-ligandhydrazide or hydrazone com plexes of 1:1 or 1:2 composition are formed. By data of xray crystallographic analysis and IRspectroscopy hydrazides or hydrazons are in ketone form and produce five-membered metallo cycles through carbonyl oxygen and nitrogen atoms of amino (or imino) groups.

In the compounds with methylpyridine hydrazide and its hydrazones two at a time five membered metallocycles are formed through atoms of oxygen of carbonyl group and heterocycle nitrogen as well as through an oxygen atom of carbonyl group and nitrogen atom of amino- and iminogroups. Central atoms of complex former have octahedral configuration.

Biological investigations of some synthesized compounds have shown a low cancerigenousicity of the complexes with orto-derivatives of hydrazides and hydrazones, which is confirmed by quan tumchemical calculations of bioactivity index of a given ligands.


Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Siberian Branch, Novosibirsk, 630090 Russian Federation. e-mail: tsvetkov@kinetics.nsc.ru Peptides containing different amount amino acid residues (trichogin-12, zervamicin-16, alamethi cin-19) are exhibiting antibiotic properties. The interest to these peptides is due to its ability to af fect the permeability of biological membranes by ion conducting channel formation.

One of the approaches to the investigation of self-aggregation of peptides is the method of spin labeling combined with cw and pulse ESR (PELDOR) techniques. The PELDOR technique will be represented. It is shown that by analyzing the kinetics of PELDOR signal decay due to magnetic dipolar interactions it is possible to fined the distance between paramagnetic centers in a pairs, dis tance distribution function F(r) in the range 15-70, to identify the radical assembling in groups and to estimate the number of the radicals in the groups.

The conformations of double labeled peptides were determined in polar frozen solutions. In apo lar solutions aggregation of peptides was found. The structures of aggregates based on geometrical parameters obtained by PELDOR are proposed. For example the analysis of PELDOR data for monolabeled trichogins in glassy weakly polar solutions shows the existence of peptide aggregates.

The distances between the labels in aggregate are around the values of 23,5 and 26, the number of peptide molecules in aggregates is about 4. From the experiments with diluted (by unlabeled pep tides) aggregates the 310-helical conformation for trichogin inside the aggregate is determined. An aggregate model of four 310-helical trichogin molecules has been proposed that is consistent with the experimental data. By using cw ESR it is shown that the aggregates are organizing in liquid so lutions of peptides in equilibrium reactions. From the motional parameters of ESR spectra the num ber of the molecules in aggregates is estimated.

Data on the structure of supramolecular aggregates of spin-labeled trichogin dimmer, zervamicin and alamethicin in apolar solutions will be presented together with its structural changes when pep tide/biolayers interaction is taking place.

This work was supported by the Russian Grant for Scientific Schools (6271-2006.3), the Russian Foundation of Ba sic Research (RFBR grant 06-04-48021-a), grant of Programme 7 Dep. of Chem. and Mather. RAS.

References 1. Yu.D. Tsvetkov. in Biological Magnetic Resonance.V.21. EPR:Instrumental Methods. Ed. C.J.Bender and L.J.Berliner. Kluwer/Plenum New York, 2004. Chapter 8, pp.385-434.

2. A.D. Milov, D.A. Erilov, E.S. Salnikov, Yu.D. Tsvetkov, F. Formaggio, C. Toniolo, and J. Raap. Phys.Chem.Chem.

Phys. v.7, 1794-1799, 3. Milov A.D., Tsvetkov Yu.D., Formaggio F., Oansea S., Toniolo C., Raap J., Phys. Chem. Chem. Phys., 2004, 6, 3596-3603.

4. A. D. Milov, R. I. Samoilova, Yu.D. Tsvetkov, M. Jost, C. Peggion, F. Formaggio, C. Toniolo, J.-W. Handgraaf, J.

Raap. Chem.Biodiv. (accepted) 2258 VIII , , PHOTOREFRACTIVE IR-RANGE COMPOSITES ON THE BASIS OF POLY(VINYL CARBAZOLE) AND RUTHENIUM(II) TETRA-15-CROWN-5-PHTHALOCYANINATES Vannikov A.V., Grishina A.D., Gorbunova Yu.G., Konnov F.Yu., Enakieva Yu.Yu., Pereshivko L.Ya., Krivenko T.V., Savel'ev V.V., Tsivadze A.Yu.

Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences 119991, Leninsky Prospect, 31, Moscow, Russia;

E-mail: van@elchem.ac.ru The photorefractive (PR) materials have great possibilities for various photonic applications. PR com posites providing the amplification and correction of the infrared information laser beams are promising, first of all, for optical medical diagnosis when biological tissue are illuminated within their transparency window, at 1064 nm, for optical telecommunication, operating at wavelength 1550 nm and for re cording, treatment and storage of optical information.

The PR effect in near IR-region in composites consisting of poly(vinyl carbazole) (PVK) and com plexes of ruthenium(II) with tetra-15-crown-5-phthalocyanine and axially coordinated CO and CH3OH molecules [(R4Pc)Ru(CO)(CH3OH)] are determined by formation of the supramolecular ensembles of the complexes, which sensitize polymer composites to near IR- region (having electron absorption at 800 1500 nm) and are thirdorder nonlinear chromophores. PVK has a high glass-transition tempera ture of 200C and therefore conserves the chaotic distribution of the nonlinear chromophores. Thus, only third order susceptibility proper to nano-dimensional , - formations has the non-zero value. Interference of two laser beams in the PR polymer layer provides the photogeneration of the electron-hole pairs in bright regions. Then electrons and holes drift in the applied electric field E0 in the opposite directions until they are captured by the deep traps. The cap- tured charges give rise to a periodic space charge field Esc that polarizes nonlinear optical chromophores and forms thereby a periodic modulation of the refractive index n, i.e.

a phase hologram. PR effect arises in the case when the 20 charges of different sings are differently shifted prior to be captured by traps. In this case, the field Esc and therefore the phase hologram is spatial shifted with respect to the interfer- 0 50 100 ence picture by phase. This shift provides the amplifica- Fig. 1. Dependence of the signal beam gain coefficient on tion of beam carrying optical information (signal beam, Is) for account of attenuation of another one (pump beam Ip). applied electric field E0.

Fig. 1 shows the field E0 dependence of the two beam gain coefficient for composite from PVK, (R4Pc)Ru(CO)(CH3OH) (5 wt.%) and ferrocene (20 wt.%), which is responsible for positive charge transport. The field dependence of the gain coefficient was measured at wavelength 1064 nm and Ip = Is. Fig. 1 shows that the net gain coefficient equals = cm-1 at E0 = 160 V/m (Here = 18 cm-1 is absorption coefficient at 1064 nm). Vertical line in Fig. shows the grow of the gain coefficient from 40 to 75 cm-1 at increase Ip /Is from 1 to 6. The two beam gain coefficient depends on modulation n and shift :

= (4ncos2 sin/). (1) The measurement of the diffraction efficiency (using third reading 633 nm beam) allowed us to de terminate n = 0.0046 and to estimate by formula (1) phase shift = 4.3. Small phase shift suggests that the charges of both signs are mobile and carried away from the interference picture by the field E over similar distances. The measurements of the drift mobility confirm this conclusion.

This work was supported by the Russian Foundation for Basic Research (projects. 05-03-33206 and 05-03-32984).

VIII , , 2007 PREDICTING STABILITIES OF METAL -ORGANIC LIGAND COMPLEXES Varnek A.a, Solovev V.P.b a Laboratoire dInfochimie, Institut de Chimie, 4, rue B. Pascal, Strasbourg 67000, France e-mail: varnek@chimie.u-strasbg.fr, URL: http://infochim.u-strasbg.fr/ b Institute of Physical Chemistry, Russ. Acad. Sci., Leninskiy prospect 31a, 119991 Moscow, Russia E-mail: solovev-vp@dio.ru This presentation concerns the COMET (COmplexation of METals) project devoted to develop ment of chemoinformatics tools able to predict stability constants for the M:L = 1:1 (logK1) and M:L = 1:2 (log2) complexes of metal cations (M) with organic ligands (L) in water.

Two approaches were used: (i) quantitative structure property modeling and (ii) linear free en ergy relationships. The first one concerns theoretical calculations with the ISIDA (In SIlico design and Data Analysis) software19 which builds quantitative structure-property relationships (QSPR) using fragment descriptors and different machine-learning techniques: multi-linear regression, sup port vector machine, artificial neural networks, k nearest neighbors. All developed models are then simultaneously applied to predict logK1 (log2) values for new ligands. Generally a consensus model calculated as arithmetic mean of values obtained with different models leads to more reliable predictions than any individual QSPR model. Models applicability domain concept was also used in order to improve the robustness of predictions.

The second approach is based on empirical correlations between stability constants for the com plexes of the given set of ligands with two different metals Mi and Mj. This approach is more re strictive than the previous one because it can be applied only for already known ligands.

In order to train structure-property models, the experimental data on complexation stability con stants from the IUPAC Stability Constants Database (SC-DB) were used. Thus, from 80000 records of SC-DB including 8600 ligands, we have selected more than 13600 logK1 and 4300 log2 values corresponding to the complexes 78 metals in their 140 cationic forms with 2962 organic ligands.

Then, these data scaled for standard temperature 298 K and ionic strength 0.1 M were used for the modeling.

Application of the developed software tools to the complexes alkaline-earth cations, transition metals and lanthanides with organic ligands is discussed.

References 1. ISIDA (In Silico Design and Data Analysis) Sofware, http://infochim.u-strasbg.fr/recherche/isida/index.php 2. Varnek A.;

Fourches D.;

Sieffert N.;

Solovev V.P.;

Hill C.;

Lecomte M. Solv. Extr. Ion Exch. 2007, 25, 1-26.

3. Tetko I. V.;

Solov'ev V. P.;

Antonov A. V.;

Yao X. J.;

Fan B. T.;

Hoonakker F.;

Fourches D.;

Lachiche N.;

Varnek A. J. Chem. Inf. Model. 2006, 46, (2), 808-819.

4. Solov'ev V. P.;

Kireeva N. V.;

Tsivadze A. Y.;

Varnek A. A. J. Struct. Chem. 2006, 47, (2), 298-311.

5. Varnek A.;

Fourches D.;

Hoonakker F.;

Solovev V. P. J. Comp.-Aided Mol. Design 2005, 19, 693-703.

6. Varnek A.;

Fourches D.;

Solov'ev V. P.;

Baulin V. E.;

Turanov A. N.;

Karandashev V. K.;

Fara D.;

Katritzky A. R.

J. Chem. Inf. Comp. Sci. 2004, 44, (4), 1365-1382.

7. Solov'ev V. P.;

Varnek A. A. Rus. Chem. Bull. 2004, 53, (7), 1434-1445.

8. Katritzky A. R.;

Fara D. C.;

Yang H.;

Karelson M.;

Suzuki T.;

Solov'ev V. P.;

Varnek A. J. Chem. Inf. Comp. Sci.

2004, 44, (2), 529-541.

9. Varnek A.;

Kireeva N.;

Tetko I. V.;

Baskin I. I.;


Laboratoire MSM, UMR CNRS 7177, Institut de Chimie, 4 rue B. Pascal, 67 000 Strasbourg (France).

wipff@chimie.u-strasbg.fr The solvation properties of Room temperature ionic liquids [M][A] can be investigated by molecu lar dynamics simulations, providing microscopic insights into the interaction between their constitu tive anions A- and cations M+ and charged versus neutral solutes. We will show examples in the context of nuclear waste partitioning by liquid liquid extraction17 and in the field of phase trans fer catalysis. Uranyl cation and its first solvation shell in the The [RhH(CO)(PPh3)3] catalyst at the [BMI][Tf2N] liquid. [BMI][PF6] hexene interface.

References 1. Chaumont, A.;

Engler, E.;

Wipff, G. Inorg. Chem. 2003, 42, 5348-5356.

2. Chaumont, A.;

Wipff, G. Inorg. Chem. 2004, 43, 5891-5901.

3. Gaillard, C.;

Chaumont, A.;

Billard, I.;

Hennig, C.;

Ouadi, A.;

Wipff, G. Inorg. Chem. 2007, 46, in press.

4. Chaumont, A.;

Wipff, G. Phys. Chem. Chem. Phys. 2006, 8, 494-502.

5. Vayssire, P.;

Chaumont, A.;

Wipff, G. Phys. Chem. Chem. Phys. 2004, 7, 124-135.

6. Sieffert, N.;

Wipff, G. Phys. Chem. A 2006, 110, 1106-1117.

7. Sieffert, N.;

Wipff, G. J. Phys. Chem. B 2006, 110, 19498-19506.

8. Sieffert, N.;

Wipff, G. J. Phys. Chem. B 2007, in press.

VIII , , 2007 A COMPLEX SUPRAMOLECULAR MACHINERY FOR SYNTHESIS OF SELENIUM CONTAINING PROTEINS Wurth L.a, Boulon S.b, Marmier-Gourrier N.c, Pradet-Balade B.b, Banlant C.c, Bertrand E.b, Charpentier B.c, Krol A.a, Allmang C.a a Architecture et Ractivit de lARN, Universit Louis Pasteur, Institut de Biologie Molculaire et Cellulaire, CNRS, Strasbourg, France.

b Institut de Gntique Molculaire, CNRS, Montpellier, France.

c Maturation des ARN et Enzymologie Molculaire, Universit Henri Poincar, CNRS, Vandoeuvre-les-Nancy, France Selenium, an essential trace element, is found in selenoproteins in the form of selenocysteine (Sec), the 21st amino acid. The majority of selenoproteins whose function is known are oxidation reduc tion enzymes using selenocysteine in their active site. Sec is encoded by a UGA codon which is normally interpreted as a stop signal by the cell protein biosynthesis machinery. This recoding process is achieved by the combined action of several RNA and protein partners acting in cis and in trans. To distinguish between the two UGA functions, a specific stem-loop located in the 3 UTR of selenoprotein mRNAs, termed Selenocysteine Insertion Sequence (SECIS), is required. Among the transacting factors, the SBP2 protein plays a major role by promoting multiple protein/RNA and protein/protein interactions. It binds the SECIS element and recruits a complex formed by the tRNASec and the specialized elongation factor EFsec. The ribosomal protein L30 is also able to bind SECIS, positioning it to the ribosomal A site and displacing SBP2 from SECIS. SBP2 belongs to the L7A/L30 family in which proteins share a homologous RNA-binding domain. In order to iden tify novel protein factors implicated in SECIS mRNP assembly, we immunopurified SBP2 associ ated complexes. We have identified new partners, and a conserved machinery which assembles pro teins of the L7A/L30 family on their target RNAs. This chaperone complex helps to guide and to fold SBP2 on the SECIS RNA. It is probably also required to recrute other new factors of the ma ture SECIS mRNP. In addition to identifying novel partners of SBP2, this study showed the high degree of complexity of SECIS mRNP assembly and selenoprotein synthesis which is far from be ing completely understood.


Institut de Gntique et de Biologie Molculaire et Cellulaire, Illkirch-Strasbourg, France marat@igbmc.u-strasbg.fr Ribosome is the macromolecular assembly responsible for protein biosynthesis in the cell. This large RNA-protein complex, 70S in prokaryotes contains two RNA molecules nearly 4 500 nucleo tides and 50 individual proteins. Total molecular mass of the ribosome is around 2, 5OO OOO Dal ton. This is only one cell organelle which was studied by x-ray analysis at atomic level.

Translation initiation is a major determinant of the overall expression level of a gene. The trans lation of functionally active protein requires the messenger RNA (mRNA) to be positioned on the ribosome in such a way that the start/initiation codon of the gene will be read first and in the correct frame. Very little is known about the molecular basis for interaction of mRNA with the ribosome at different states of translation.

Recent crystal structures 70S ribosome containing functional ligands provided information about the general organization of the ribosome and its functional centers1. We have crystallized and com pared X-ray structures of several ribosome complexes modeling translation initiation, post-initiation and elongation states2. In the initiation and post-initiation complexes, the presence of the Shine Dalgarno (SD) duplex causes strong anchoring of the 5-end of mRNA on the platform of the 30S subunit, where numerous interactions between mRNA and the ribosome take place. Conversely, the 5-end of the elongator mRNA lacking SD interactions is flexible suggesting a different exit path for mRNA during elongation. The post-initiation ribosome complex reveals that after initiation of translation, while SD interaction is still present, mRNA moves in the 3-5 direction with simulta neous clockwise rotation and lengthening of the SD duplex.

References 1. M Yusupov, G Yusupova, A Baucom, K Liberman, L Lancaster, T Earnest, J Cate, H Noller, Science 2001, 292, 2. G Yusupova, L Jenner, B Rees, D Moras, M Yusupov, Nature 2006, 444, VIII , , 2007 SUPRAMOLECULAR BIOCHEMICAL SYSTEMS OF THE ANIMAL BLOOD Zaitsev S.Yu.a, Maksimov V.I.a, Bardukova T.V.b a FGOY VPO Moscow State Academy of Veterinary Medicine and Biotechnology named by K. I. Skryabin, Akad. Skryabin Str. 23, Moscow 109472, Russia;

b Veterinary Clinic Centr, Tsvetnoi bulvar 11, Moscow 127051, Russia The complexes of biologically active compounds of humans and animals blood plasma can be con sidered as native supramolecular biochemical systems. In is especially actual for various blood plasma enzymes which have complicated structures and particular multicomponent combinations.

For example, lactate dehydrogenase (LDG) consists of the 4 protein subunits of one or two types (H- and M-subunits) and has 5 isoenzyme forms (from H4 or LDG1 and H3M or LDG2 localized mainly in heart muscle;

till M4 or LDG5 mainly in liver). Another enzymes: kreatine kinase (KK) consists of the 2 protein subunits of one or two types (M- and B-subunits) and has 3 isoenzyme forms (KK-MM, KK-MB, KK-BB);

aspartate aminotransferase (AST) and alanine aminotransferase (ALT) consist of the 2 protein subunits (each enzyme) and so on1.

We have studied these enzymes in the blood plasma of healthy and ill dogs of various age and sex. The extremely high increase of the activity for all enzymes has been found for rather old male dogs (10-11 years old) with heart disease as compared to middle-aged male dogs. Especially pro nounced changes in the enzyme activity has been found for the LDG1 (in 15 times) and LDG2 (in times) isoenzyme forms, as well as for the KK-MB and KK-MM isoenzyme forms (in about 4 times total) as compared to the activities of the same isoenzyme forms of the healthy animals1.

These results have not only support the fundamental necessity to study the particular combina tions of the enzymes and their isoenzyme forms in the blood plasma of healthy animals, but also proved their importance for clinical diagnostics of some diseases.

This work was supported by Rector of the FGOY VPO MSAVM&B named by K. I. Skryabin.

References 1. T. V. Bardukova, S. Yu. Zaitsev S. Yu., V. I. Maksimov Veterinary medicine (Rus.) 2006, 2-3, 28.



Institute of Chemical Biology and Fundamental Medicine SB RAS.

8, Lavrentiev ave., Novosibirsk 630090, Russian Federation Design of artificial ribonucleases is one of the most challenging tasks in RNA targeting. Apart from being useful molecular biology tools, such compounds may provide new opportunities for design of therapeutics targeting viral genomic RNAs. Artificial ribonucleases usually consist of two domains connected by a flexible linker: a catalytic domain is responsible for RNA cleavage while an RNA binding domain recognizes RNA and provides interaction of artificial ribonuclease with the RNA.

We design and investigated ribonucleases activity of several series of artificial ribonucleases (aR Nases) designated as ABnLkCm, nDm, nLm, Dxn conjugates of potential catalytic groups and cationic structures and demonstrated that some of the compounds display pronounced RNA cleav ing activity. Rate enhancement of RNA cleavage by some of aRNases is 107-108 fold as compared with non-catalyzed reaction. These compounds cleave RNA at Y-A Y-C C-N (were Y is pyrimidine and N any base).

The conjugate built of nanodeoxyribonucletide and the peptide [Leu-Arg]4-Gly-amide connected by a linker of three abasic deoxyribonucleotides (conjugate pep-9) cleaving RNA exclusively at G X linkages under various conditions was identified by rational screening. Rate enhancement of RNA cleavage at G-X linkages catalyzed by pep-9 is 108 as compared to non-catalyzed reaction, pep-9 cleaves these linkages only 105 fold less efficiently then RNase T1.

The potential of the aRNases as probes for investigation of RNA structure in solution and as antivirals was studied. We demonstrated that aRNases display a high RNA structure and sequence specificity. Moreover some of the compounds are able to inactivate Influenza virus. Treatment of influenza virus with aRNase prior to infection entirely destroys viral genomic RNA and prevents development of virus infection in MDCK cells, in embryonated chicken eggs and in mice. Thus, aRNases represent a new class of compounds capable of inactivation of RNA containing viruses This work was supported by Russian Academy of Sciences (Programs Molecular and Cellular Biology and Sci ences to Medicine), RFBR grant no. 05-04-49109, and Euler/DAAD fellowships References 1. Giege R., et al, Meth. Enzymol., 2000, 318, 147-165;

2. Zenkova M.A., et al, Meth. Enzmol., 2001, 341, 468-490;

3. Mironova N.L., et al, Nucleic Acids Res., 2004, 32, 1028-1936;

4. Artificial Nucleases, Ed. Marina Zenkova in Nucleic Acids and Molecular Biology, Springer Verlag, 2004, 13.;

5. Kovalov N., et al., Nucleosides, Nucleotides and Nucleic acids, 2004, 23, 977-982;

6. Kuznetsova I.L., et al, Nucleic Acids Res., 2005, 33, 1201-1212;

7. Mironova N.L., et al, J. Biomol. Struct. Dyn. 2006, 23, 591 602;

8. Kovalev N., et al., Bioorganic Chemistry 2006. 34. 274-286;

9. Mironova N.L., et al., Nucleic Acids Res., 2007, V. 35(7), in press.

2266 VIII , , PICOSECOND TIME-RESOLVED FLUORESCENCE OF HEMICYANINE LANGMUIR-BLODGETT FILMS Abraham E.a, Grauby-Heywang C.a, Selector S.b, Jonusauskas G.a a CPMOH, University Bordeaux 1, CNRS UMR 5798, 351 cours de la Libration, Talence cedex, France, e-mail: em.abraham@cpmoh.u-bordeaux1.fr b Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninsky pr., 31 4, GSP-1, 119991, Moscow, Russia Hemicyanine Langmuir-Blodgett (LB) films can be employed to conceive functionalized artificial membranes by incorporating light-sensitive molecular units designed to introduce specific trans membrane functionalities such as light-to-electrical energy conversion and sensor capabilities.

In this work, 4-[4-(dimethylamino)styryl]-1-docosylpyridium bromide has been used for the formation of LB films. The study of the hemicyanine at the air-water interface and the elaboration process of the LB films are detailed in another abstract (Structure of Langmuir monolayers and Langmuir-Blodgett films of hemicyanine, S. Selector et al.). Here, we will focus on the photo physical characterization of the films using steady-state and time-resolved spectroscopic methods.

Indeed, it is of primary importance to understand the photodynamics of the films after photoexcita tion for a later functionalization of the films, such as light-harvesting, energy transfer, sensor capa bilities. Especially, a time-resolved fluorescence technique was adopted to determine quantitatively, with a picosecond resolution time, the emission lifetimes of hemicyanine in LB films transferred under different experimental conditions. This method was coupled to steady-state absorption and fluorescence measurements. Results show that the behaviour of hemicyanine depends strongly on the subphase pH.

In the case of films transferred at 30 mN/m from a monolayer formed on subphase pH 10, we observed a main absorption band around 460 nm and an emission band centered on 605 nm. With the streak camera, we measured the transient fluorescence of the film and revealed interesting fea tures concerning the time-resolved fluorescence of the film. Just after excitation at 480 nm, we first observed an emission band around 570 nm that was not observed in steady-state fluorescence. The time decay of this new emission band is very short (1 = 23 ps). After the time decay of the new emission band at 570 nm, another emission band centered near 595 nm develops with a bi exponential decay time with 2 = 120 ps and 3 = 550 ps. At pH=4, the absorption spectrum of the film reveals a new absorption band near 360 nm that could be reasonably attributed to the emission of the chromophore containing protonated dimethylaminogroup.

At last, in the case of films transferred at surface pressure higher than 20mN/m, the absorption spectra revealed the formation of H-aggregates (blue-shifted absorption band around 420 nm). The intensity of the absorption band of the H-aggregates depends on the incident polarization of the light and on the orientation of the film indicating that the H-aggregates (dimmers for instance) have a nearly perpendicular orientation with respect to the quartz plate. Furthermore measurements at polarized light showed the presence of strong aggregate dipole moment orientation in the transfer direction. With the streak camera, we investigated the relationship between the LB film orientation and the intensity and lifetime of the fluorescence decay.

VIII , , 2007 LUMINESCENCE CHARACTERISTICS OF THE POLYMER COMPOSITION CONTAINING NANOAGGREGATES OF SOLUBILIZED BY PLURONICS EUROPIUM DIKETONATES Aksenova N.A., Glagolev N.N., Shashkova V.T., Zaichenko N.L., Kol`tsova L.S., Shiyonok A.I., Mardaleishvili I.R., Timashev P.S., Zapadinskyy B.I., Solovieva A.B.

119991, Moscow, Kosygin str., 4, N.N. Semenov Institute of chemical physics The main problems of photosensitive and light resistant polymer compositions preparation are sta bilizing within matrix of photoactive compound (PAC) such as complex europium -diketonates, with linear size less than 1 mkm and achieving of uniform distribution of such particles inside the matrix. Most effectively these problems can be solved by solubilizing of injected particles with bi phylic substances. Usually they are non-ionic surfactant which are soluble in hydrophobic polymer matrix.

In this paper it was shown that triple block copolymers ethylene and propylene oxides (pluron ics) can be used as suitable surfactant solubilizer of PAC. It was shown that luminescence intensity (I615) of some solubilized complex -europium diketonates injected by evaporation of combined solutions into PMMA increase by 5 times comparing with intensity of nonsolubilized luminophore.

We suggest that luminophore solubilization causes PAC aggregate size decrease;

I615 increase is caused by reducing of concentrative dissipation effect that is determined by luminophore molecules interactions inside these aggregates. In the same time no changes of I615 detected for solubilized complex europium -diketonates dissolved in OKM-2 before its curing. It supposed that pluronic with molecular mass 2090 during the process of curing is pressed out from high density system (molecular mass internodal segment is 418) and also destruction of luminophor-pluronic association is happened. This way main part of pack is located within polymer matrix in nonsolubilized form.

The conclusion about particle size of complex europium -diketonates pluronics solubilized made based on AFM analysis of crystallized pluronic agglomerate structure on mica surface from its solu tion in chloroform. It was made with and without luminophore presence in solution. Without lu minophore pluronics is crystallized on mica surface as dendrite-like (tree-like) structure. However after evaporation of europium -diketonates and pluronic chlorophorm solutions associations crys tallized on mica surface has structure of independent islands with linear size about 200-500 nm.

We acknowledge the Basic Research Programme of RAS Presidium References 1. D. Harvey. Modern Analytical Chemistry. Boston 2000, 798.

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