Kurepina N E, Basyuk E I, Metlitskaya A Z, Zaitsev D A, Khmel I A
Institute of Molecular Genetics, Russian Academy of Sciences, Moscow.
Mol Gen Genet. 1993 Dec;241(5-6):700-6. doi: 10.1007/BF00279914.
Microcin C51 is a small peptide antibiotic produced by Escherichia coli cells harbouring the 38 kb low copy number plasmid pC51, which codes for microcin production and immunity. The genetic determinants for microcin synthesis and immunity were cloned into the vectors pBR325, pUC19 and pACYC184. Physical and phenotypic analysis of deletion derivatives and mutant plasmids bearing insertions of transposon Tn5 showed that a DNA fragment of about 5 kb is required for microcin C51 synthesis and expression of complete immunity to microcin. Partial immunity can be provided by a 2 kb DNA fragment. Mutant plasmids were tested for their ability to complement Mic- mutations. Results of these experiments indicate that at least three plasmid genes are required for microcin production. The host OmpR function is also necessary for microcin C51 synthesis.
微菌素C51是由携带38 kb低拷贝数质粒pC51的大肠杆菌细胞产生的一种小肽抗生素，该质粒编码微菌素的产生和免疫。微菌素合成和免疫的遗传决定因素被克隆到载体pBR325、pUC19和pACYC184中。对携带转座子Tn5插入的缺失衍生物和突变体质粒的物理和表型分析表明，微菌素C51的合成和对微菌素的完全免疫表达需要一个约5 kb的DNA片段。一个2 kb的DNA片段可提供部分免疫。测试了突变体质粒互补Mic-突变的能力。这些实验结果表明，微菌素的产生至少需要三个质粒基因。宿主OmpR功能对于微菌素C51的合成也是必需的。
