Involvement of cytochrome bc 1 complex in the electron transfer pathway for N2O reduction in a photodenitrifier, Rhodobacter sphaeroides f. s. denitrificans

FEBS Letters

Matsuura, Katsumi¹  Itoh, Masahiko¹  Satoh, Toshio² 

[1] Department of Biology, Tokyo Metropolitan University, Fukazawa 2-1-1, Setagaya, Tokyo 158 Japan;Botanical Institute, Faculty of Science, Hiroshima University, Higashi-senda-machi 1-1-89, Hiroshima 730, Japan

关键词: Cytochrome bc 1 complex;    Cytochrome c 2;    N2O reduction;    Nitrous oxide;    Denitrification;    (Rhodobacter sphaeroides);    TMPD;    N;    N;    N′;    N′-tetramethyl-p-phenylene-diamine;    CCCP;    carbonyl cyanide m-chlorophenylhydrazone;    Pipes;    piperazine-N;    N′-bis-(2-ethanesulfonic acid);    BChl;    bacteriochlorophyll;   

DOI  :  10.1016/0014-5793(89)81437-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The electron transfer pathway for N₂O reduction in Rhodobacter sphaeroides f. s. denitrificans was studied. Myxothiazol and antimycin showed inhibiting effects on the consumption of N₂O in whole cells grown under photo-denitrifying conditions. This indicated the involvement of the cytochrome bc ₁ complex in the process. Reduced redox dyes that donate electrons directly to cytochrome c ₂ overcame this inhibition. Similar results were obtained with Rhodobacter capsulatus, in contrast to earlier studies by McEwan et al. [(1985) J. Bacteriol. 164, 823–830] that suggested the lack of involvement of the cytochrome bc ₁ complex in this process. Effects of myxothiazol and antimycin were also observed on the N₂O-induced oxidation of cytochromes c ₁ and c ₂ and on the simultaneous generation of membrane potential measured by the carotenoid band shift. Thus, reducing equivalents for N₂O reduction from substrates pass through the cytochrome bc ₁ complex coupling to the generation of an electrochemical gradient of protons.

【 授权许可】

Unknown