Department of Bacteriology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan.
Genes (Basel). 2021 Sep 28;12(10):1527. doi: 10.3390/genes12101527.
is a bacterium that mainly colonizes the nasal cavity and skin. To colonize the host, it is necessary for to resist many antibacterial factors derived from human and commensal bacteria. Among them are the bacteria-derived antimicrobial peptides (AMPs) called bacteriocins. It was reported that some two-component systems (TCSs), which are signal transduction systems specific to bacteria, are involved in the resistance to several bacteriocins in . However, the TCS-mediated resistance is limited to relatively low concentrations of bacteriocins, while high concentrations of bacteriocins still exhibit antibacterial activity against . To determine whether we could obtain highly bacteriocin-resistant mutants, we tried to isolate highly nisin A-resistant mutants by exposing the cells to sub-minimum inhibitory concentrations (MICs) of nisin A. Nisin A is one of the bacteriocins produced by and is utilized as a food preservative worldwide. Finally, we obtained highly nisin A-resistant mutants with mutations in one TCS, BraRS, and in PmtR, which is involved in the expression of . Notably, some highly resistant strains also showed increased pathogenicity. Based on our findings, this review provides up-to-date information on the role of TCSs in the susceptibility to antibacterial peptides. Additionally, the mechanism for high antimicrobial peptides resistance and its association with pathogenicity in is elucidated.
是一种主要定植于鼻腔和皮肤的细菌。为了定植于宿主，需要抵抗来自人和共生菌的许多抗菌因子。其中包括被称为细菌素的细菌来源的抗菌肽（AMPs）。据报道，一些双组分系统（TCSs），即细菌特有的信号转导系统，参与了对几种的抵抗。然而，TCS 介导的抗性仅限于相对较低浓度的细菌素，而高浓度的细菌素仍对表现出抗菌活性。为了确定我们是否可以获得高度耐细菌素的突变体，我们尝试通过将细胞暴露于低于最小抑菌浓度（MIC）的乳链菌肽 A 来分离高度耐乳链菌肽 A 的突变体。乳链菌肽 A 是由产生的一种细菌素，在全球范围内被用作食品防腐剂。最后，我们获得了在一个 TCS（BraRS）和参与表达的 PmtR 中发生突变的高度耐乳链菌肽 A 的突变体。值得注意的是，一些高度抗性的菌株也表现出了增加的致病性。基于我们的发现，这篇综述提供了关于 TCS 在对抗菌肽敏感性中的作用的最新信息。此外，阐明了在中高抗菌肽抗性的机制及其与致病性的关系。
