REGULATION OF ISOCITRATE DEHYDROGENASE ACTIVITY IN ESCHERICHIA-COLI ON ADAPTATION TO ACETATE
REGULATION OF ISOCITRATE DEHYDROGENASE ACTIVITY IN ESCHERICHIA-COLI ON ADAPTATION TO ACETATE
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DOI：
10.1099/00221287-65-1-57
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发表时间：
1971-01-01
期刊：
影响因子：
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通讯作者：
BENNETT, PM
中科院分区：
文献类型：
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作者：
HOLMS, WH;BENNETT, PM
大肠埃希菌在葡萄糖+盐培养基中需氧生长，分泌乙酸盐。在葡萄糖耗尽时，细胞合成乙醛酸旁路的酶，乙醛酸旁路允许以乙酸盐作为唯一的碳和能量来源生长。同时，异柠檬酸脱氢酶的活性福尔斯下降到20%，当乙酸耗尽时，恢复到原始水平的75%。在不促进乙酸盐排泄的底物（例如甘油）上生长后获得类似结果，条件是在生长结束时向培养基中添加乙酸盐。这种对异柠檬酸脱氢酶活性的控制显然是一种机制，它限制了碳在三羧酸循环中的流动，有利于乙醛酸旁路的运行。
Escherichia coligrown aerobically in glucose + salts medium excretes acetate. On glucose exhaustion, the cells synthesize the enzymes of the glyoxylate bypass which permits growth on acetate as sole source of carbon and energy. Concurrently, the activity of isocitrate dehydrogenase falls to 20% and, when the acetate is exhausted, is restored to 75% of the original level. Similar results are obtained after growth on substrates (e.g. glycerol) which do not promote excretion of acetate, provided acetate is added to the medium at the end of growth. This control of isocitrate dehydrogenase activity is apparently a mechanism which restricts the flow of carbon round the tricarboxylic acid cycle and favours operation of the glyoxylate bypass.