Old yellow enzyme: reduction of nitrate esters, glycerin trinitrate, and propylene 1,2-dinitrate.

ABSTRACT: The reaction of the old yellow enzyme and reduced flavins with organic nitrate esters has been studied. Reduced flavins have been found to react readily with glycerin trinitrate (GTN ) (nitroglycerin) and propylene dinitrate, with rate constants at pH 7.0, 25 degrees C of 145 M(-1)s(-1) and 5.8 M(-1)s(-1), respectively. With GTN, the secondary nitrate was removed reductively 6 times faster than the primary nitrate, with liberation of nitrite. With propylene dinitrate, on the other hand, the primary nitrate residue was 3 times more reactive than the secondary residue. In the old yellow enzyme-catalyzed NADPH-dependent reduction of GTN and propylene dinitrate, ping-pong kinetics are displayed, as found for all other substrates of the enzyme. Rapid-reaction studies of mixing reduced enzyme wi

SUBMITTER: Meah Y 

PROVIDER: S-EPMC37475 | biostudies-literature | 2001 Jul

REPOSITORIES: biostudies-literature