大肠杆菌K12中的氧化磷酸化。一种膜结构改变的解偶联突变体。

Oxidative phosphorylation in Escherichia coli K12. An uncoupled mutant with altered membrane structure.

Cox G B, Gibson F, McCann L

Biochem J. 1974 Feb;138(2):211-5. doi: 10.1042/bj1380211.

Abstract

A new mutant strain (AN228) of Escherichia coli K12, unable to couple phosphorylation to electron transport, has been isolated. The mutant allele (unc-405), in strain AN228, was found to map near the uncA and uncB genes at about minute 74 on the E. coli genome. 2. A transductant strain (AN285) carrying the unc-405 allele is similar to the uncA and uncB mutants described previously in that it is unable to grow on succinate, gives a low aerobic yield on limiting concentrations of glucose, has a normal rate of electron transport, is unable to couple phosphorylation to electron transport, and lacks ATP-dependent transhydrogenase activity. 3. Strain AN285 (unc-405) is similar to an uncA mutant, but different from an uncB mutant, in that it is unable to grow anaerobically in a glucose-mineral-salts medium, and membrane preparations do not have Mg(2+)-stimulated adenosine triphosphatase activity. 4. Strain AN285 (unc-405) does not form an aggregate analogous to the membrane-bound Mg(2+)-stimulated adenosine triphosphatase aggregate found in normal cells. In this respect it differs from strain AN249 (uncA(-)), which forms an inactive membrane-bound Mg(2+)-stimulated adenosine triphosphatase aggregate.

摘要

已分离出大肠杆菌K12的一种新突变株（AN228），它无法将磷酸化与电子传递偶联。发现突变株AN228中的突变等位基因（unc - 405）位于大肠杆菌基因组约74分钟处的uncA和uncB基因附近。2. 携带unc - 405等位基因的转导菌株（AN285）与先前描述的uncA和uncB突变体相似，即它不能在琥珀酸盐上生长，在有限浓度的葡萄糖上有氧生长产量低，具有正常的电子传递速率，无法将磷酸化与电子传递偶联，并且缺乏ATP依赖性转氢酶活性。3. 菌株AN285（unc - 405）与uncA突变体相似，但与uncB突变体不同，因为它不能在葡萄糖 - 矿物质 - 盐培养基中厌氧生长，并且膜制剂不具有Mg(2 +)刺激的腺苷三磷酸酶活性。4. 菌株AN285（unc - 405）不形成类似于正常细胞中发现的膜结合Mg(2 +)刺激的腺苷三磷酸酶聚集体的聚集体。在这方面，它与菌株AN249（uncA(-)）不同，后者形成无活性的膜结合Mg(2 +)刺激的腺苷三磷酸酶聚集体。