[Formation of collagen type I fibrils in vitro].

The assembly of collagen fibrils as a function of temperature and collagen concentration was studied. It was shown that temperature increases from 25 to 35 degrees C, the degree of ordering of collagen fibrils increases 1.5-fold at collagen concentration above 1 mg/ml and 2-fold at low collagen concentration.

[Self-assembly of collagen type I molecules without telopeptides].

The effect of temperature on the kinetics of formation of fibrils from rat tail collagen molecules devoid of telopeptides was studied. It was shown that the rats of fibril formation at 30 and 35 degrees C increases five- and eightfold, respectively, as compared with that at 25 degrees C. It was found that enthalpy of fibril denaturation at 30 degrees C is maximal for the collagen both with intact telopeptides and devoid of telopeptides.

[Structural differences in the collagens of Rana frog species with dissimilar temperature ecology. The contribution of carbohydrate components to collagen molecular thermostability].

Skin procollagens in two species groups of frogs of the genus Rana - brown frogs (4 species) and green frogs (3 species) distributed in European and Asiatic parts of the USSR have been compared. A geographic intraspecific variation in collagen characteristics (two geographic populations of the pond frog Rana nigromaculata) is revealed. Intergroup differences in the thermal denaturation of collagens established by means of methods of circular dichroism and microcalorimetry are significant.

[Structure of histone fragments and their models. I. Structural features of N-terminal oligopeptides of histone H4].

Circular dichroism (CD) and infrared spectroscopy (IRS) studies of aqueous solutions of fourth N-terminal peptides of histone H4 with different chain length were carried out under various conditions. It was shown that all studied peptides had conformation of extended left-handed helix as well as poly-1-proline II at the acidic and neutral pH, in moderate ionic strength (0,15), in 80% ethanol, 0,2 M sodium dodecylsulphate, in 8 M urea and 5 M guanidinum hydrochloride. This conformation was changed by raising temperature, under transition to the range of basic pH and in the concentrated solutions of CaCl2 (5M).