The Lon protease is highly evolutionarily conserved. However, little is known about Lon in the context of gut microbial communities. A gene encoding a Lon-like protease (Lon-like-Ms) was identified and characterized from Methanobrevibacter smithii, the predominant archaeon in the human gut ecosystem. Phylogenetic and sequence analyses showed that Lon-like-Ms and its homologs are newly identified members of the Lon family. A recombinant form of the enzyme was purified by affinity chromatography, and its catalytic properties were examined. Recombinant Lon-like-Ms exhibited ATPase activity and cleavage activity toward fluorogenic peptides and casein. The peptidase activity of Lon-like-Ms relied strictly on Mg²⁺ (or other divalent cations) and ATP. These results highlight a new type of Lon-like protease that differs from its bacterial counterpart.

中文翻译：

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史密斯甲烷短杆菌中ATP依赖的Lon-like蛋白酶的表征。

Lon蛋白酶在进化上是高度保守的。但是，在肠道微生物群落的背景下，对Lon的了解很少。从人类肠道生态系统中最重要的古细菌史密斯甲烷杆菌中鉴定并鉴定了一种编码Lon样蛋白酶的基因（Lon like-Ms）。系统发育和序列分析表明，Lon-like-Ms及其同源物是Lon家族的新成员。通过亲和层析纯化重组形式的酶，并检查其催化性能。重组的Lon-like-Ms表现出对荧光肽和酪蛋白的ATPase活性和切割活性。Lon-like-Ms的肽酶活性严格依赖于Mg ²⁺（或其他二价阳离子）和ATP。这些结果突出了一种新型的Lon样蛋白酶，不同于其细菌对应物。