Impermeant electron acceptors and donors to the plasma membrane bound respiratory chain of intact cyanobacterium anacystis nidulans
Peschek, G.A.; Kurz, M.A.; Erber, W.W.A.
Physiologia Plantarum 73(1): 175-181
1988
ISSN/ISBN: 0031-9317
DOI: 10.1111/j.1399-3054.1988.tb09213.x
Accession: 005639091
Membrane-impermeant redox compounds ferricyanide and horse heart ferrocytochrome c acted as electron acceptor and donor, respectively, for intact cells or spheroplasts of Anacystis nidulans (Synechococcus ATCC 27144) in the dark. The anaerobic reduction of ferricyanide was faster than aerobic reduction. KCN significantly enhanced the reaction under conditions. Light did not influence ferricyanide reduction. The oxidation of exogenous ferrocytochrome c was oxygen-dependent and inhibited by KCN. Either type of redox reaction was accompanied by vectorial proton translocation out of the cells. Arrhenius plots for the temperature dependence of both ferricyanide reduction and cytochrome c oxidation gave one distinct break point reflecting the lipid phase transition temperature of the plasma membrane. The results are presented as evidence for a respiratory chain in the plasma membrane of A. nidulans.