肠道菌分泌的抑菌肽——小菌素

摘要

Microcins are antibacterial peptides produced by Enterobacteria with low molecular masses below10 kDa. They are encoded by cluster genes on the plasmid or on the genome. Microcins have narrow antibacterial spectrum. They have potent antibacterial activity against closely related bacteria in Enterobacteria. Typical gene clusters in microcins include microcin precursor gene, the self-immunity gene, the secretion gene and frequently the post-translational modification gene. Microcins are ribosomally synthesized as precursors, in contrast to most microbial antibiotics that are non-ribosomally synthesized. Fifteen microcins have been discovered so far. They show a variety of structures and antibacterial mechanisms.%小菌素是由肠道菌分泌的一类小分子抑菌肽, 分子量小于10kDa, 由细菌质粒或基因组上相关基因簇编码, 小菌素的抑菌谱较窄, 仅对肠道菌中部分亲缘较近的菌种发挥有效的抑菌效应.编码小菌素的基因簇一般包括几个部分:前体基因, 自身免疫基因, 分泌基因, 转录后修饰基因.与很多微生物通过非核糖体途径分泌抑菌物质不同, 小菌素前体通过核糖体途径分泌.目前已发现的小菌素有15种, 它们的结构和抑菌机制具有多样性.