[Penta-peptide (YFRKD) suppression of complex conditioned-reflex activities in the ontogeny of white rats]. / Podavlenie penta-peptidom (YFRKD) slozhnoi uslovnoreflektornoi deiatel'nosti v ontogeneze belykh krys.

Influence of YFRKD, modified fragment of interferon-alpha, on the formation of two-links system of feed-procuring conditioned reflexes was studied in rats in ontogenesis. The experiments have shown that YFRKD impedes both current learning and use of previous experience. The process of synthesis of two reflexes in united complicated functional complex is disturbed.

[An alternative model of structural organization of the ternary complex antigen-protein MHC II-TCR]. / Al'ternativnaia model' strukturnoi organizatsii troinogo kompleksa antigen-belok MHC II -TCR.

An alternative model of organization of the structure of ternary complex "antigen-molecule" of the main complex of histocompatible class II (MHC II)--antigenic receptor of T-cells (TCR) is suggested. In contrast to the already developed ones the new model foresees TCR interaction with only one (beta)-chain of the molecule MHC (II), with its surface site having the structure of alpha-spiral. The second (alpha)-chain of the molecule MHC II performs only antigen-binding and supporting function. According to the structure of the code of amino acids interaction a comparative analysis of the roots (bases of the second nucleotides) of amino acid codons of fragments of alpha-, beta-, and gamma-invariant chains of MHC II, as well as some antigens and immunoregulators. An expressed similarity of the structures of spiral fragment of beta- and gamma-chains of MHC II both between themselves and with certain antigens and natural immunoregulators.

[Structural similarity of the active sites of major histocompatibility complex class I proteins and ubiquitin]. / Skhodstvo struktur aktivnykh tsentrov belkov glavnogo kompleksa gistosovmestimosti klassa I i ubikvitina.

With the help of a new method of protein primary structures analysis, i.e. CAACRA (comparative amino acid codon root analysis) a marked structural similarity of the MHC class I protein active sites and ubiquitin alpha-helix has been revealed. Using the CAACRA a periodicity of ubiquitin primary structure has been shown. Ubiquitin molecule consists of 4 repeat units.

[Structure and organization of class I interferon molecules]. / Struktura i organizatsiia molekul interferonov I klassa.

The regular structure of class I interferon molecules was proposed using the new method of protein structure investigation--the comparative analysis of amino acids codon roots. It was found out that IFN-alpha and IFN-omega molecules are formed of 5 repeats. Each repeat can be divided into two parts or blocks with regular (alpha-spiral, block A) and irregular (parts of molecules between alpha-spirals, block B) structures. Localization of blocks A and B in IFN-alpha molecules has good correlation with the models of secondary structure organization of IFN-alpha. It is supposed that such a structure of IFN molecules is formed in the evolution process as a result of multiplication of IFN primary gene.

[Hidden symmetry of peptide and protein primary structures]. / Skrytaia simmetriia pervichnykh struktur peptidov i belkov.

The internal symmetry of peptide chains was considered. To identify symmetrically located equivalent amino acids, the signatures method and the code of amino acid codon roots were applied. There was revealed the hidden symmetry of amino acid sequences of peptides and proteins as well as of their active centres. Amino acids having common codon roots in primary (and supposedly in the spatial "biologically active") molecular structures, are located symmetrically. Definition of local symmetry of peptide chains was proposed to use as one of the elements of complex analysis to determine location of molecular active centres.

[A model of intra- and intermolecular interactions of peptide chains]. / Model' vnutri- i mezhmolekuliarnogo vzaimodeistviia peptidnykh tsepei.

Results of attempts to determine the code of interaction of amino acids in peptide chains proceeding from their coding nucleotide sequences have been summarized. According to the model suggested the G/C and A/U complementarity of codon roots determines the mutual binding of coded amino acid residues. Structures of analogs of the immunoactive peptide, a fragment of IgG1 (336-370) EPQVY have been constructed on the basis of the model.

[Folding of peptide chains during formation of the spatial structure of protein molecules is determined by the code of amino acid codon roots]. / Svorachivanie peptidnykh tsepti pri obrazovanii prostranstvennykh struktur molekul belkov opredeliaetsia kodom kornei kodonov aminokislot.

Basing on the analysis of a large number of protein sequences (Cserzo M., Simon I., 1989), the structure of the amino acid nearest neighbour pair whose occurrence has a maximal positive deviation from the mean statistical value, is shown to correspond in most cases to the code of the amino acid codon roots. It reveals particularly amino acid pairs in n and n+5 positions of polypeptide chains. Amino acids belonging to A/U family contribute mostly to the folding of peptide chains.

[Antagonistic properties of tetra-substituted analog of vasopressin with selective antidiuretic effects]. / Antagonisticheskie svoistva chetyrekhzameshchennogo analoga vazopressina s selektivnym antidiureticheskim deistviem.

Biological properties of a novel vasopressin analogue were investigated. It was found that this analogue has no vasopressor and oxytocic activities but it exhibits a selective antidiuretic effect which is weaker than that of adiuretin (DDAVP). Novel analogue inhibits vasopressor, oxytocic and antidiuretic effects caused by arginine--vasopressin. The usefulness of novel compound as a pharmacological tool--vasopressin antagonist is suggested.

[Code of codon roots of amino acids and idiotypic networks]. / Kod kornei kodonov aminokislot i idiotipicheskie seti.

Novel models of idiotype nets of antibodies have been developed to study the code responsible for the amino acid interaction and complex formation of proteins. It is shown that the interaction of protein active centres in idiotype nets can be interpreted and predicted basing on the structure of code of codon roots of amino acids and polarity principle. "Internal images" of the sequence antigen determinants of proteins in immunoglobulin molecules are built mainly from the amino acid groups having common codon roots, which is in agreement with the conception of the structure of the root code.

[Interaction code for polar and nonpolar amino acids: "ice-breaker" model]. / Kod vzaimodeistviia poliarnykh i apoliarnykh aminokislot: model' "ledokola"]

A novel model for the study of recognition and interaction code of amino acids in peptides, proteins and their complexes has been proposed. The model is designed on the modern notions on the structure and properties of water and hydrophobic bonds. It is assumed that the polar side chains of amino acids during the formation of the hydrophobic bonds act as "ice-breaker", thus destroying the organized structure of water (clusters or "icebergs") around the hydrophobic radicals of amino acids.

[Code of codon roots, determining the intra- and intermolecular interaction of amino acids in peptide chains]. / Kod kornei kodonov, opredeliaiushchii vnutri- i mezhmolekuliarnoe vzaimodeistvie aminokislot v peptidnykh tsepiakh.

To study the recognition processes and interaction of peptides and proteins, a model has been suggested according to which the first steps of complex formation of molecules are defined by G/C and A/U complementarity of codon roots of amino acid forming the molecules contact sites or surfaces. In contrast to amino acid--antiamino acid interaction code (L. B. Mekler, 1969), the code of codon roots involves the interaction of amino acids independently of the base structures in nucleotide triplets in positions 1 and 3. The analysis of the spectra of point mutations homologous proteins confirms the possible role of the root code.

[Hidden symmetry of the genetic code and laws of amino acid interaction]. / Skrytaia simmetriia geneticheskogo koda i zakonomernosti vzaimodeistviia aminokislot.

Natural amino acids having common antiamino acids are divided into families and groups according to the algorithm of the genetic code (a-n-n-a, amino acid-codon-anticodon-antiamino acid). Members of these groups are placed symmetrically in the structure of the genetic code. In the course of evolution, those point mutations are predominantly accepted retained. In homologous proteins of phylogenetically related organisms which lend to amino acids belonging to one family or group and having common antiamino acids. This assumption is in agreement with L. B. Mekler's theory (1969) of the amino acid interaction code a-a.

[The slowing of the extinction of a conditioned reaction and the antiamnesic action of arginine vasopressin and des-glycine-(8-arginine) vasopressin]. / Zamedlenie ugasheniia uslovnoi reaktsii i antiamnezicheskoe deistvie arginin-vazopressina i dez-glitsin-(8-arginin)-vazopressina.

In the experiments on mice there were analysed the effects of arginine-vasopressin (AVP) and its analogue des-glycine-arginine-vasopressin (DG-AVP) on the extinction of the conditioned reaction of passive avoidance and the reproduction of memory trace in amnesia caused by detaining the animal in the dangerous section of the unit after electrocutaneous stimulation. An increase of resistance of the conditioned reaction to a sharp extinction at systemic administration of AVP and DG-AVP was shown.

[Polarity and hydropathic properties of natural amino acids]. / Poliarnost' i gidropatichnye svoistva prirodnykh aminokislot.

A new classification of amino acids according to their polarity and symmetric location in the spatial structure of the genetic code is suggested. The polar amino acids are: R, S (codons AGC and AGU), K, N, Q, H, W, C, Y, G, E, D; apolar ones are: T, M, I, P, L, S (codons UCN). Polar and apolar amino acids are grouped into three families whose members possess complementarity with respect to the symmetric structure of the genetic code. Interaction of these complementary polar and apolar amino acids encodes formation of the space structures and ligand-receptor complexes of proteins. Correlation between the polar and hydropathic properties of amino acids is investigated. Normalization of 38 hydrophobicity scales of natural amino acids is carried out. A discrepancy between structures of polar/hydrophilic and apolar/hydrophobic groups of amino acids is demonstrated. According to the signature principle this discrepancy is due to different properties of amino acid side radicals which, in turn, depend on the second component of the reaction and on environmental conditions.

[Regrouping of peptide chains in molecules and molecular complexes: recognition and spatial conjugation codes of amino acids]. / Peregruppirovka peptidnykh tsepei molekul i molkuliarnykh kompleksov: kod uznavaniia i kod prostranstvennoi sopriazhennosti aminokislot.

A two-step model for reactions between peptide and protein molecules in aqueous medium is considered. The first stage of the reaction involves specific recognition and primary complex formation. This process is governed by the amino acid interaction code a-a as a part of genetic code (algorithm a-n-n-a, amino acid-codon-anticodon-anti-amino acid). According to the a-a code, the primary complex formation is determined by amino acid pairs of opposite polarity. During the second stage of the reaction, when the contacting ligand and receptor surfaces undergo dehydration, the primary complex becomes rearranged. The new structure is mainly determined by pairwise contacts of amino acids having similar polarity and belonging to the same amino acid family.