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A I Denesiuk

Publications and source records attributed to A I Denesiuk.

7 recordsLinked to original sources
PubMedDate not supplied

[Wide-angle x-ray scattering comparison of the structure of crystalline cytochrome c and cytochrome c in solution].

Large-angle X-ray diffuse scattering has been used for studying the conformational changes in cytochrome c during its transition from crystal into solution and during a change of the electron state of the heme. It has been found that the structure of cytochrome c in solution differs from its structure in crystal by a shift of the chain fragment in the region of 60-77 amino acid residues. The studies of the oxidized, reduced and cyanoforms of protein in solution have not revealed noticeable changes in the protein structure.

Chemical Phenomena↗
PubMedDate not supplied

[Theoretical and experimental studies on the conformation of the hinge regions in human immunoglobulin G subclasses].

Using the methods of difference adiabatic scanning microcalorimetry and difference thermal perturbation spectrophotometry it was established that both the Fc subunits within the intact immunoglobulins G of different subclasses, and the Fc fragments corresponding to them significantly differ in conformational properties. These differences are associated with a different energy of interactions between the CH2 and CH3 domains and also with a different rigidity of structure of the N- and C-terminal parts of the CH2 domains. The analysis of these data allowed to suggest that the "hinge region" interacts with the CH2 domains and the difference in the structure of this region affect the conformation of the Fc subunits. Possible models of the "hinge regions" in immunoglobulins G of the first, second and fourth subclasses, and also their arrangement relative to the CH2 domains were proposed. The analysis of curves of the small-angle scattering of X-rays shows an agreement between the theoretical models and experimental data.

Calorimetry, Differential Scanning↗
PubMedDate not supplied

[Comparison of the structures of different forms of sperm whale myoglobin in solution using wide angle x-ray scattering].

Experimental X-ray diffuse scattering curves in a wide range of angles for oxy-, deoxy-, met- and cyan-forms of sperm whale myoglobin in solution have been obtained. It has been found that scattering indicatrices of these ligand forms of myoglobin are well compatible with each other and differ from the theoretical scattering curve of met-myoglobin, calculated from the structure of this protein in crystal. The conclusions have been drawn: (1) on the similarity of myoglobin structures in solution for all the protein forms studied; (2) on the difference in the structure of the above ligand forms of myoglobin in solution from the structure of the protein in crystal by a slight shift (about 2 A) of the "hairpin" GH.

Animals↗