Western Regional Research Center, U. S. Department of Agriculture, 800 Buchanan Street, Albany, California 94710.
Plant Physiol. 1988 Dec;88(4):987-9. doi: 10.1104/pp.88.4.987.
Direct evidence is presented for the lack of a pH change in the medium associated with electron flow along the alternative, cyanide-resistant pathway in Arum maculatum mitochondria. When these mitochondria oxidize succinate via the cytochrome chain, the medium becomes acidified. However, when the main respiratory chain is blocked by cyanide or antimycin A, oxygen consumption continues, but no pH change occurs. This confirms the lack of a charge separation across the membrane, so that phosphorylation cannot be supported during operation of the alternative oxidase.
本文直接证明了在菝葜线粒体中,沿著替代的、对氰化物有抗性的途径进行电子流时,介质中不存在 pH 值变化。当这些线粒体通过细胞色素链氧化琥珀酸时,介质会酸化。然而,当主要呼吸链被氰化物或抗霉素 A 阻断时,耗氧量仍在继续,但 pH 值没有变化。这证实了在膜两侧没有电荷分离,因此在替代氧化酶的作用下不能进行磷酸化。