Beardmore-Gray M, Anthony C
J Gen Microbiol. 1986 May;132(5):1257-68. doi: 10.1099/00221287-132-5-1257.
The coupling of the quinoprotein glucose dehydrogenase to the electron transport chain has been investigated in Acinetobacter calcoaceticus. No evidence was obtained to support a previous suggestion that the soluble form of the dehydrogenase and the soluble cytochrome b associated with it are involved in the oxidation of glucose. Analysis of cytochrome content, and of reduction of cytochromes in membranes by substrates, and of sensitivity to cyanide indicated that glucose, succinate and NADH are all oxidized by way of the same b-type cytochrome(s) and cytochrome oxidases (cytochrome o and cytochrome d). Mixed inhibition studies [with KCN and hydroxyquinoline N-oxide (HQNO)] showed that the b-type cytochrome(s) formed a binary complex with the o-type oxidase and that there was thus no communication between the electron transport chains at the cytochrome level. Measurements of the reduction of ubiquinone-9 by glucose and NADH, and inhibitor studies using HQNO, indicated that the ubiquinone mediates electron transport from both the glucose and NADH dehydrogenases. In some conditions the quinone pool facilitated communication between the 'glucose oxidase' and 'NADH oxidase' electron transport chains, but in normal conditions these chains were kinetically distinct.
已在醋酸钙不动杆菌中研究了醌蛋白葡萄糖脱氢酶与电子传递链的偶联。没有获得证据支持先前的一种观点，即脱氢酶的可溶形式及其相关的可溶性细胞色素b参与葡萄糖的氧化。对细胞色素含量、底物对膜中细胞色素的还原作用以及对氰化物的敏感性分析表明，葡萄糖、琥珀酸和NADH均通过相同的b型细胞色素和细胞色素氧化酶（细胞色素o和细胞色素d）进行氧化。混合抑制研究[使用KCN和羟基喹啉N - 氧化物（HQNO）]表明，b型细胞色素与o型氧化酶形成二元复合物，因此在细胞色素水平上电子传递链之间没有通讯。通过葡萄糖和NADH对泛醌 - 9的还原测量以及使用HQNO的抑制剂研究表明，泛醌介导来自葡萄糖脱氢酶和NADH脱氢酶的电子传递。在某些条件下，醌池促进了“葡萄糖氧化酶”和“NADH氧化酶”电子传递链之间的通讯，但在正常条件下这些链在动力学上是不同的。
