Glutathione mediation of papain inactivation by hydrogen peroxide and hydroxyl radicals. [Gamma radiation]

Journal Article · Tue Mar 01 04:00:00 EST 1977 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3574656· OSTI ID:7306788

Lin, W S; Armstrong, D A

Glutathione reacts with papainCys/sub 25/SOH, formed by the reaction of papain with hydrogen peroxide, to give papainCys/sub 25/SSG. Subsequent reaction of this mixed disulfide with glutathione is slow (k < 3 M/sup -1/ sec/sup -1/). However, at 30/sup 0/C it is readily cleaved by cysteine to form active papain, i.e., papainCys/sub 25/SH. Glutathione resembles cysteine in protecting papain by the scavenging of .OH radicals, but, unlike cysteine, glutathione gave no evidence for the repair of enzyme radical lesions or for the conversion of papainCys/sub 25/S. radicals to repairable derivatives. Its overall effectiveness for reducing the radiation inactivation of papain in aqueous solution is much less than that of cysteine.

• Research Organization: Univ. of Calgary, Alberta
• OSTI ID: 7306788
• Journal Information: Radiat. Res.; (United States), Journal Name: Radiat. Res.; (United States) Vol. 69:3; ISSN RAREA
• Country of Publication: United States
• Language: English

Related Subjects

560111* -- Radiation Effects on Biochemicals-- In Vitro-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINO ACIDS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
CARBOXYLIC ACIDS
CYSTEINE
ELECTROMAGNETIC RADIATION
ENZYMES
GAMMA RADIATION
GLUTATHIONE
HYDROGEN COMPOUNDS
HYDROGEN PEROXIDE
HYDROLASES
HYDROXYL RADICALS
INACTIVATION
IONIZING RADIATIONS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXYGEN COMPOUNDS
PAPAIN
PEPTIDE HYDROLASES
PEPTIDES
PEROXIDES
POLYPEPTIDES
PROTEINS
RADIATION EFFECTS
RADIATIONS
RADICALS
RADIOINDUCTION
THIOLS