Pohane Amol Arunrao, Jain Vikas
Microbiology and Molecular Biology Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal 462023, India.
Microbiology (Reading). 2015 Dec;161(12):2269-76. doi: 10.1099/mic.0.000190. Epub 2015 Sep 28.
Antibiotics are the molecules of choice to treat bacterial infections. However, because of the rapid emergence of drug-resistant bacteria, alternative modes of combating infections are being envisaged. Bacteriophages, which infect and lyse bacterial cells, may function as effective antimicrobial agents. Most bacteriophages produce their own peptidoglycan hydrolase called endolysin or lysin, which breaks down the cell wall of bacteria and aids in the release of newly assembled virions. Here, we discuss several findings that help us in understanding how endolysins are regulated. We observe that there is no common mechanism that is followed in all cases. Many different modes of activity regulation have been observed in endolysins, including regulation of protein expression, translocation across the cell membrane and post-translational modifications. These processes not only demonstrate how endolysins are made dependent on other accessory proteins and non-protein factors for their synthesis, translocation across the cytoplasmic membrane and activity, but also show how autoregulation helps in maintaining the enzyme in an inactive form. Various regulatory mechanisms that are discussed are particularly applicable to endolysins. Nevertheless, a detailed study of these methods opens new avenues of investigation in the area of protein translocation systems and the novel ways of enzyme activation and regulation in bacteria.
抗生素是治疗细菌感染的首选分子。然而，由于耐药菌的迅速出现，人们正在设想对抗感染的替代方式。感染并裂解细菌细胞的噬菌体可能作为有效的抗菌剂发挥作用。大多数噬菌体产生一种名为内溶素或溶素的自身肽聚糖水解酶，它能分解细菌的细胞壁并有助于新组装的病毒粒子的释放。在此，我们讨论了几项有助于我们理解内溶素如何被调控的研究发现。我们观察到并非所有情况都遵循共同的机制。在内溶素中已观察到许多不同的活性调控模式，包括蛋白质表达的调控、跨细胞膜的转运以及翻译后修饰。这些过程不仅展示了内溶素如何在其合成、跨细胞质膜转运和活性方面依赖于其他辅助蛋白和非蛋白因子，还展示了自动调控如何有助于将酶维持在无活性形式。所讨论的各种调控机制特别适用于内溶素。然而，对这些方法的详细研究为蛋白质转运系统领域以及细菌中酶激活和调控的新方式开辟了新的研究途径。
