Rodríguez E, Laviña M
Sección de Fisiología y Genética Bacterianas, Facultad de Ciencias, Tristán Narvaja, Montevideo, Uruguay.
Can J Microbiol. 1998 Jul;44(7):692-7. doi: 10.1139/cjm-44-7-692.
Microcin H47 is a bactericidal antibiotic produced by a natural Escherichia coli isolate. The genetic system encoding microcin production and immunity consists of at least seven clustered genes. Four of these are devoted to microcin biosynthesis and two genes are required for its secretion into the extracellular medium. The product of the seventh gene, mchI, determines the cell's self-immunity. This gene was shown to encode a highly hydrophobic 69-residue peptide. Analysis of the MchI amino acid sequence, as well as the characterization of MchI-PhoA hybrid proteins, indicated that the microcin immunity product is probably exported out of the cytoplasm and remains an integral membrane peptide. This localization of the immunity peptide points to the cellular membrane as the site of action of microcin H47.
微菌素H47是由一株天然大肠杆菌分离株产生的杀菌性抗生素。编码微菌素产生和免疫的遗传系统至少由七个成簇基因组成。其中四个基因负责微菌素的生物合成，另外两个基因是其分泌到细胞外培养基所必需的。第七个基因mchI的产物决定了细胞的自身免疫性。该基因被证明编码一种高度疏水的69个氨基酸残基的肽。对MchI氨基酸序列的分析以及MchI-PhoA融合蛋白的特性表明，微菌素免疫产物可能从细胞质中输出，并仍然是一种整合膜肽。免疫肽的这种定位表明细胞膜是微菌素H47的作用位点。
