Maleyacetone cis-trans-isomerase: affinity chromatography on glutathione-bound sepharose. Two-substrate-binding sequence from inhibition patterns
Journal Article
·
· Biochemistry; (United States)
OSTI ID:7251095
Maleylacetone cis-trans-isomerase isolated from Vibrio 01 binds glutathione strongly; K/sub m/ = 1.4 x 10/sup -4/ M. Oxidized glutathione and S-methylglutathione are competitive inhibitors, K/sub I/ = 9.4 x 10/sup -4/ and 1.2 x 10/sup -3/ M, respectively. Based on these interactions, three different glutathione-bound agarose affinity absorbents were synthesized and tested. Affinity chromatography of the isomerase with one of these affords 70- to 100-fold purifications. In separate syntheses portions of the affinity arm were prepared and examined as to their inhibitory properties in the enzyme-catalyzed reaction. The fragment, containing glutathione bound through its sulfur to the carbon chain, is a powerful competitive inhibitor for glutathione (K/sub I/ = 6 x 10/sup -5/ M). The results described suggest that the isomerase binds glutathione through the backbone of the tripeptide and that the thiol group is required for activity. The initial velocity patterns of the enzyme-catalyzed reaction resulting from simultaneous variation of glutathione and maleylacetone concentrations were examined in the absence and presence of inhibitors resembling glutathione. The observed kinetic patterns suggested an ordered sequence of binding: maleylacetone first followed by glutathione.
- Research Organization:
- Brookhaven National Lab., Upton, NY
- OSTI ID:
- 7251095
- Journal Information:
- Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 15:19; ISSN BICHA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Maleylacetone cis-trans-isomerase. Mechanism of the interaction of coenzyme glutathione and substrate maleylacetone in the presence and absence of enzyme
Enzymatic function in crystals of. delta. /sup 5/-3-ketosteroid isomerase: catalytic activity and binding of competitive inhibitors
Unique, one-step, double isomerization (2E, 4Z in equilibrium 2Z, 4E) of 6-oxo-2,4-heptadienoic acid catalyzed by maleylacetone cis-trans isomerase
Journal Article
·
Wed May 23 00:00:00 EDT 1979
· J. Am. Chem. Soc.; (United States)
·
OSTI ID:6063052
Enzymatic function in crystals of. delta. /sup 5/-3-ketosteroid isomerase: catalytic activity and binding of competitive inhibitors
Journal Article
·
Wed Jul 25 00:00:00 EDT 1984
· J. Biol. Chem.; (United States)
·
OSTI ID:5132771
Unique, one-step, double isomerization (2E, 4Z in equilibrium 2Z, 4E) of 6-oxo-2,4-heptadienoic acid catalyzed by maleylacetone cis-trans isomerase
Journal Article
·
Sat Dec 31 23:00:00 EST 1983
· J. Am. Chem. Soc.; (United States)
·
OSTI ID:6992733