Neuer G, Bothe H
Biochim Biophys Acta. 1982 Jun 16;716(3):358-65. doi: 10.1016/0304-4165(82)90028-9.
Heterocyst preparations have been obtained which actively perform nitrogen fixation (C2H2 reduction) and contain the enzymes of glycolysis and some of the tricarboxylic acid cycle. Pyruvate: ferredoxin oxidoreductase has been unambiguously demonstrated in extracts from heterocysts by the formation of acetylcoenzyme A, CO2 and reduced methyl viologen (ferredoxin) from pyruvate, coenzyme A and oxidized methyl viologen (ferredoxin) as well as by the synthesis of pyruvate from CO2, acetylcoenzyme A and reduced methyl viologen. Pyruvate supports C2H2 reduction by isolated heterocysts, however, with lower activity than Na2S2O4 and H2. alpha-Ketoglutarate: ferredoxin oxidoreductase is absent in Anabaena cylindrica, confirming that the organism has an incomplete tricarboxylic acid cycle.
已获得能积极进行固氮作用（乙炔还原）并含有糖酵解酶和部分三羧酸循环酶的异形胞制剂。通过丙酮酸、辅酶A和氧化型甲基紫精（铁氧化还原蛋白）生成乙酰辅酶A、二氧化碳和还原型甲基紫精（铁氧化还原蛋白），以及由二氧化碳、乙酰辅酶A和还原型甲基紫精合成丙酮酸，已在异形胞提取物中明确证实了丙酮酸：铁氧化还原蛋白氧化还原酶的存在。丙酮酸能支持分离出的异形胞进行乙炔还原，但其活性低于连二亚硫酸钠和氢气。圆筒鱼腥藻中不存在α-酮戊二酸：铁氧化还原蛋白氧化还原酶，这证实该生物体的三羧酸循环不完整。
