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PubMedDate not supplied

[Emergence of a quasi-periodic spatial structure in the model of aggregation of moving, dividing cells, possessing chemotactic properties].

It has been analyzed the Keller-Segel model of aggregation of divided cells possessed hemotaxis. During the cell division homogeneous stationary distribution becomes unstable due to increasing of the common cells amount. It is shown that accidental variation of the primary stable homogeneous stationary distribution result to forming of a like periodical space structure with characteristic scale that basically is defined by the cell division rate. This approach allows to explain the arising of complex space structures in the movable bacterium colonies.

Animals↗
PubMedDate not supplied

[A compressed form for presenting data to banks on the primary and spatial structure of biopolymers. Means for accessing compressed data banks].

Description of open CAN format (Compressed Amino acids and Nucleotides) is presented for storing genetic information in compressed form in data banks (DB). Data compression principles are demonstrated in detail on examples of EMBL DB (sequences of nucleotides), SWISSPROT DB (sequences of amino acids) and PDB DB (3D structures). A unified compressed data format provides a possibility to integrate EMBL, SWISSPROT, and PDB DB in one data bank. We are going to use this approach for integration of GENBANK and other similar DBs. One of the outcomes of the research is a library of data retrieval procedures for access to DB, providing developers of the application software packages with a uniform interface to DBs with biologically related data. The proposed scheme for data representation was recommended by the Expert Commission of the Informatics Section of the RSSIP "Human Genome" as a standard for distribution of data banks in Russia.

Amino Acid Sequence↗
PubMedDate not supplied

[Artificial proteins with a given spatial structure and biological activity].

Biologically active fragment 131-138 of human interferon alpha 2 carrying blast-transforming activity of the protein was attached to the N-terminus of the de novo protein albebetin with predetermined tertiary structure by means of genetic engineering. The chimeric protein was expressed in a wheat germ cell-free translation system and tested for compactness, stability and biological activity. According to the tests used albebetin with interferon fragment has a compact and relatively stable structure. It binds murine thymocyte receptor with high affinity and activates efficiently thymocyte blast transformation at a concentration of 10(-11) M.

Amino Acid Sequence↗
PubMedDate not supplied

[Analysis of the spatial structure of proteins in terms of residue-residue contacts. II. Contact affinity].

The possibility of detecting the mutual amino acid residue affinity when protein three-dimensional structures are described in terms of residue-residue contact matrices is discussed. The hypothesis of the lack of affinity between amino acid residues is examined; the values of the pertinent elements of the overall residue-residue contact matrices prove not to be statistically different from random estimates in 91%; the chance hypothesis is rejected in 9% of cases, represented as a rule by residues with charged side groups, especially oppositely charged ones.

Amino Acids↗
PubMed1995

[Refinement of the spatial structure of neurotoxin II from Naja naja oxiana venom].

A set of 19 conformations of the neurotoxin II from Naja naja oxiana was determined by conformational energy minimization using constraints derived from experimental 1H NMR data. The pairwise average root-mean-square deviations were 0.86 A for the backbone heavy atoms and 1.48 A for all heavy atoms of these conformations. A model of the neurotoxin II dimer is proposed to account for the relatively slow deuterium exchange rates of the Val45 and Leu51 amide protons, which are exposed to the solvent in the calculated conformations of monomeric neurotoxin II. Both the monomeric and dimeric models of neurotoxin II may be useful for detailed studies of the functional, hydrophobic, and electrostatic properties of this molecule.

Amino Acid Sequence↗
PubMedDate not supplied

[Modification of the DNA spatial structure when complexed with cisplatin].

The experimental and theoretical analyses of the conformational transitions of DNA-cis-platinum complexes have been carried out. It is shown that at low concentrations of the ligand, the thermodynamic parameters of the helix-coil transition of the complexes are not the result of the local B-->A transition.

Animals↗