Abstract

A terminal oxidase of the Escherichia coli K12 respiratory chain (cytochrome b562-o complex) was reconstituted into liposomes by freeze-thaw/sonication method. Formation of a membrane potential (-145 mV) by the reconstituted cytochrome b562-o complex was observed with the fluorescent dye 3,3'-dipropylthiodicarbocyanine iodide on addition of an artificial electron donor ubiquinol-1 or ascorbate-phenazine methosulfate. The membrane potential formed was inhibited by the protonophore uncouplers 3,5-di-tert-butyl-4-hydroxybenzylidenemalononitrile, carbonyl cyanide p-trifluoromethoxyphenylhydrazone, and carbonylcyanide m-chlorophenylhydrazone, and the inhibitors of the oxidase system zinc sulfate, potassium cyanide, and 2-n-heptyl-4-hydroxyquinoline-N-oxide. This is the first indication that there is a coupling site in an E. coli terminal oxidase, which consists of b-type cytochromes.

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.