Semrau Jeremy D, DiSpirito Alan A, Obulisamy Parthiba Karthikeyan, Kang-Yun Christina S
Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI, USA 48109-2125.
Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, USA 50011.
FEMS Microbiol Lett. 2020 Mar 1;367(5). doi: 10.1093/femsle/fnaa045.
Aerobic methane-oxidizing bacteria of the Alphaproteobacteria have been found to express a novel ribosomally synthesized post-translationally modified polypeptide (RiPP) termed methanobactin (MB). The primary function of MB in these microbes appears to be for copper uptake, but MB has been shown to have multiple capabilities, including oxidase, superoxide dismutase and hydrogen peroxide reductase activities, the ability to detoxify mercury species, as well as acting as an antimicrobial agent. Herein, we describe the diversity of known MBs as well as the genetics underlying MB biosynthesis. We further propose based on bioinformatics analyses that some methanotrophs may produce novel forms of MB that have yet to be characterized. We also discuss recent findings documenting that MBs play an important role in controlling copper availability to the broader microbial community, and as a result can strongly affect the activity of microbes that require copper for important enzymatic transformations, e.g. conversion of nitrous oxide to dinitrogen. Finally, we describe procedures for the detection/purification of MB, as well as potential medical and industrial applications of this intriguing RiPP.
已发现α-变形菌纲的需氧甲烷氧化细菌表达一种名为甲烷菌素（MB）的新型核糖体合成的翻译后修饰多肽。在这些微生物中，MB的主要功能似乎是用于摄取铜，但MB已被证明具有多种能力，包括氧化酶、超氧化物歧化酶和过氧化氢还原酶活性、解毒汞物种的能力，以及作为抗菌剂的作用。在此，我们描述了已知MB的多样性以及MB生物合成的遗传学基础。基于生物信息学分析，我们进一步提出一些甲烷营养菌可能产生尚未被表征的新型MB形式。我们还讨论了最近的研究结果，这些结果表明MB在控制更广泛微生物群落的铜可用性方面发挥着重要作用，因此会强烈影响需要铜进行重要酶促转化（例如将一氧化二氮转化为氮气）的微生物的活性。最后，我们描述了检测/纯化MB的方法，以及这种有趣的翻译后修饰多肽的潜在医学和工业应用。
