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O B Ptitsyn

Publications and source records attributed to O B Ptitsyn.

At least 73 records · Page 4Linked to original sources
PubMed1975

A model of myoglobin self-organization.

The self-organization of helical regions of myoglobin into a compact tertiary structure is considered on the basis of the hypothesis on the step-wise mechanism of self-organization of protein molecules. It is assumed that the self-organization begins with the formation of "centers of crystallization" and proceeds with the growth of on such center or by a sequential collapse of two or more grown centers. Different pathways of self-organization of myoglobin are considered; the most favourable structures corresponding to the greatest number of dehydrated bulky hydrophobic groups and to all the strongly hydrophilic groups exposed to water are selected at every stage of the given pathway and the others are neglected. One of the two most favourable structures obtained in such a way coincides in rough resolution with the native tertiary structure of protein.

Animals↗
PubMed1975

The structure of hydrophobic cores of globins.

The contacts between bulky hydrophobic side chains (Val, Leu, Ile, Met, Phe, Tyr, and Trp) were studied in five globins with known three-dimensional structures. It is shown that a large majority of these side chains participate in such contacts, where most often one side chain makes contact with two to four nearby side chains. The "recognition element" of a helical region is most often a pair of bulky hydrophobic side chains belinging to neighboring turns of an alpha-helix. Such pairs most often make contact with bulky hydrophobic side chains brought in from the outside. An analysis is made of contacts between the hydrophobic side chains common to all five globins. It is shown that as a rule the most intense contacts in each globin are also common to the five globins. The role of these invariant contacts in the formation of the tertiary structure of globin molecules is considered. A suggestion is made that the apoglobin molecule consists of independently self-organizing halves, the internal structure of which is less subject to fluctuation than their mutual arrangement.

Amino Acid Sequence↗