The misuse of antibiotics during the last decades led to the emergence of multidrug resistant pathogenic bacteria. This phenomenon constitutes a major public health issue. Consequently, the discovery of new antibacterials in the short term is crucial. Colicins, due to their antibacterial properties, thus constitute good candidates. These toxin proteins, produced by E. coli to kill enteric relative competitors, exhibit cytotoxicity through ionophoric activity or essential macromolecule degradation. Among the 25 colicin types known to date, colicin M (ColM) is the only one colicin interfering with peptidoglycan biosynthesis. Accordingly, ColM develops its lethal activity in E. coli periplasm by hydrolyzing the last peptidoglycan precursor, lipid II, into two dead-end products, thereby leading to cell lysis. Since the discovery of its unusual mode of action, several ColM orthologs have also been identified based on sequence alignments; all of the characterized ColM-like proteins display the same enzymatic activity of lipid II degradation and narrow antibacterial spectra. This publication aims at being an exhaustive review of the current knowledge on this new family of antibacterial enzymes as well as on their potential use as food preservatives or therapeutic agents.

中文翻译：

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大肠杆菌素 M 及其直向同源物的生物学

在过去几十年中滥用抗生素导致了多重耐药病原菌的出现。这种现象构成了一个重大的公共卫生问题。因此，在短期内发现新的抗菌药物至关重要。大肠菌素，由于它们的抗菌特性，因此是很好的候选物。这些毒素蛋白由大肠杆菌产生以杀死肠道相关竞争者，通过离子载体活性或必需的大分子降解表现出细胞毒性。在迄今为止已知的 25 种大肠菌素类型中，大肠菌素 M (ColM) 是唯一一种干扰肽聚糖生物合成的大肠菌素。因此，ColM 在大肠杆菌中发挥了其致死活性通过将最后的肽聚糖前体脂质 II 水解成两个死端产物，从而导致细胞裂解。自从发现其不寻常的作用方式以来，还根据序列比对确定了几种 ColM 直向同源物；所有表征的 ColM 样蛋白都显示出相同的脂质 II 降解酶活性和狭窄的抗菌谱。本出版物旨在对这一新抗菌酶家族的当前知识以及它们作为食品防腐剂或治疗剂的潜在用途进行详尽的回顾。