RADIATION-INDUCED DAMAGE OF CYSTEINE RESIDUES IN DIHYDROOROTATE DEHYDROGENASE IN DILUTE AQUEOUS-SOLUTION

Authors
SAHA A MANDAL PC BHATTACHARYYA SN
Citation
A. Saha et al., RADIATION-INDUCED DAMAGE OF CYSTEINE RESIDUES IN DIHYDROOROTATE DEHYDROGENASE IN DILUTE AQUEOUS-SOLUTION, Radiation physics and chemistry, 48(1), 1996, pp. 61-63
Citations number
12
Categorie Soggetti
Nuclear Sciences & Tecnology","Chemistry Physical","Physics, Atomic, Molecular & Chemical
Journal title
Radiation physics and chemistry → ACNP
ISSN journal
0969806X
Volume
48
Issue
1
Year of publication
1996
Pages
61 - 63
Database
ISI
SICI code
0969-806X(1996)48:1<61:RDOCRI>2.0.ZU;2-J
Abstract
The effect of gamma-radiation on thiol groups of cysteine residues in dihydroorotate dehydrogenase was investigated. The G-values for thiol loss in various conditions were determined by modified Ellman's method . The result shows that G(-SH) in aerated condition is higher than tha t in deaerated conditions. This indicates that oxygen plays an importa nt role in radiation-induced damage of the enzyme-bound SH groups. The determination of surface-exposed thiol groups of unirradiated and irr adiated samples shows that irradiation causes partial unfolding of the enzyme molecules. Copyright (C) 1996 Elsevier Science Ltd.