PHYSICO-CHEMICAL INVESTIGATION OF THE MECHANISM OF ENZYME INACTIVATION. PART III. THERMODYNAMIC ANALYSIS OF STRUCTURAL AND CHEMICAL CHANGES IN PROTEIN DURING RADIATION INACTIVATION

Abstract

A method for studying the structural and chemical changes during the individual stages of the radiation inactivation of enzymes is proposed, which consists of applying the Eyring-Stearn method of thermodynamic analysis of protein denaturing to the thermal radiation after-effect reaction. It was shown by this method that in the process of formation of latent damage in the myosin and pepsin molecules 10-15 hydrogen bonds are ruptured, but the covalent bonds are not ruptured; in the second stage of inactivation -- upon realization of the latent damage -- the rupture of one covalent bond (apparently the disulfide bond) and 3-4 hydrogen bonds takes place. The hypothesis is expressed that the rupture of the hydrogen bonds in the first stage of inactivation takes place due to the Platzman-Franck polarization effect, but only after preliminary migration and localization of the charge at 'weak' sites of the structure, particularly at the S-S bridges. 'Fusion' of sections of the protein molecule in this region during the first stage of inactivation guarantees the possibility of carrying out the second stage.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Oct 17, 1967
Accession Number
AD0677828

Entities

People

  • L. Kh. Eidus

Organizations

  • United States Army Biological Warfare Laboratories

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Covalent Bonds
  • Experimental Data
  • Hydrogen
  • Hydrogen Bonds
  • Molecular Orbital Theory
  • Molecules
  • Radiation
  • Radiation Effects
  • Thermal Radiation
  • Translations

Readers

  • Molecular and Cellular Biochemistry
  • Quantum Chemistry