Cardelli J, Konisky J
J Bacteriol. 1974 Aug;119(2):379-85. doi: 10.1128/jb.119.2.379-385.1974.
Two classes of spontaneous colicin I insensitive mutants of Escherichia coli have been isolated. The first class (called cir) has lost its ability to adsorb either colicin Ia or Ib, maps at 41 min on the E. coli genetic map, and retains sensitivity to all other colicins tested. The cir phenotype is probably due to an alteration in the colicin I receptor. The second class of mutant (called tolI) retains full capacity to adsorb [(125)I]colicin I and, therefore, represents the isolation of a mutant tolerant to colicin I. The tolI mutant is sensitive to all other colicins tested and has a map location of 89-1 min. The tolI mutant grows with a reduced mass yield when glucose is used as a carbon source and cannot utilize succinate or acetate for growth. The tolI mutant shows a reduced sensitivity to sodium azide and phenethylalcohol. It is suggested that tolI is deficient in some aspect of aerobic metabolism which must be operative for colicin I sensitivity.
已分离出两类对大肠杆菌素I自发不敏感的突变体。第一类（称为cir）已丧失吸附大肠杆菌素Ia或Ib的能力，位于大肠杆菌遗传图谱的41分钟处，并且对测试的所有其他大肠杆菌素仍保持敏感。cir表型可能是由于大肠杆菌素I受体的改变。第二类突变体（称为tolI）保留了完全吸附[（125）I]大肠杆菌素I的能力，因此代表了对大肠杆菌素I耐受的突变体的分离。tolI突变体对测试的所有其他大肠杆菌素敏感，其图谱位置为89 - 1分钟。当使用葡萄糖作为碳源时，tolI突变体生长时质量产量降低，并且不能利用琥珀酸盐或乙酸盐进行生长。tolI突变体对叠氮化钠和苯乙醇的敏感性降低。有人提出，tolI在有氧代谢的某些方面存在缺陷，而这对于大肠杆菌素I的敏感性必须起作用。
