Abstract

NADH-cytochrome c reductase (diaphorase), a functional moiety of the spinach NADH-nitrate reductase complex, uses one molecule of NADH to reduce two of ferricytochrome c. Initial velocity experiments in the absence of products produce patterns of parallel lines when plotting 1/ v vs. 1/(substrate) at different fixed concentrations of the other substrate. The results agree with a Ping Pong mechanism in which the first product (NAD +) is released, with formation of a reduced free form of the enzyme, prior to binding of the first molecule of the second substrate (ferricytochrome c). Product inhibition experiments indicate the production of an abortive complex between NAD + and the oxidized enzyme form that binds NADH. The data are consistent with a Hexa Uni Ping Pong mechanism in which an abortive complex is formed between NAD + and the enzyme form binding NADH.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.