1. Several ring-substituted derivatives of diphenyleneiodonium catalyse the exchange of Cl- and OH- ions across the inner membrane of rat liver mitochondria. They also inhibit state 3 and state 3u oxidations of glutamate plus malate in the presence of Cl- more than in its absence. Most have activities similar to diphenyleneiodonium, although 2,4-dichlorodiphenyleneiodonium is up to 50 times more active. 2. Diphenyleneiodonium inhibits soluble rat liver NADH dehydrogenase and NADH oxidation by rat liver sub-mitochondrial particles directly; 2,4-dichlorodiphenyleneiodonium is only about twice as inhibitory. 3. Liver mitochondria contain two classes of binding sites for diphenylene[125I]iodonium, namely high-affinity sites with an affinity constant of 3 X 10(5) M-1 (1–2 nmol/mg of protein), and low-affinity sites with an affinity constant of 1.3 X 10(3) M-1 (80 nmol/mg of protein). Both sites occur in hepatocytes with a relative enrichment of the low-affinity site. Nadh dehydrogenase preparations only apparently contain high-affinity binding sites. Only low-affinity sites occur in erythrocytes. 4. 2,4-Dichlorodiphenyleneiodonium competes with diphenylene[125I]iodonium for both low- and high-affinity sites, whereas tri-n-propyltin only competes for the low-affinity sites. 5. The high-affinity sites are apparently associated with NADH dehydrogenase and the low-affinity sites probably represent electrostatic binding of diphenylene[125I]iodonium to phospholipids. The high-affinity site does not appear to be associated with a rate-limiting stage of NADH oxidation.
Skip Nav Destination
Follow us on Twitter @Biochem_Journal
Article navigation
August 1976
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkAdvertising
Research Article|
August 15 1976
The effects of diphenyleneiodonium on mitochondrial reactions. Relation of binding of diphenylene[125I]iodonium to mitochondria to the extent of inhibition of oxygen uptake Available to Purchase
Publisher: Portland Press Ltd
Online ISSN: 1470-8728
Print ISSN: 0264-6021
© 1976 London: The Biochemical Society
1976
Biochem J (1976) 158 (2): 307–315.
Citation
S J Gatley, H S A Sherratt; The effects of diphenyleneiodonium on mitochondrial reactions. Relation of binding of diphenylene[125I]iodonium to mitochondria to the extent of inhibition of oxygen uptake. Biochem J 15 August 1976; 158 (2): 307–315. doi: https://doi.org/10.1042/bj1580307
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
Biochemical Society Member Sign in
Sign InSign in via your Institution
Sign in via your InstitutionGet Access To This Article
Cited By
Follow us on Twitter @Biochem_Journal
Open Access for all
We offer compliant routes for all authors from 2025. With library support, there will be no author nor reader charges in 5 journals. Check here |
![]() View past webinars > |