Abstract
Xanthine oxidase (XO) was shown to catalyze the reduction of isoamyl and isobutyl nitrites to nitric oxide (NO) in the presence of xanthine under anaerobic conditions. NO was produced at a stoichiometric ratio of 2:1 versus urate generation, steady-state analysis of which showed Michaelis–Menten kinetics with xanthine as varied substrate and substrate inhibition with varied organic nitrite. Under the conditions of NO generation from isoamyl nitrite, XO was progressively inactivated by a mechanism involving conversion of MoS to MoO, yielding “desulfo” enzyme. It is proposed that XO is involved in the metabolism of organic nitrites to NO in vivo and that the observed inactivation serves to explain the phenomenon of tolerance.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Biochemical and Biophysical Research Communications
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.