Characterization of the ATP-Dependent Lon-Like Protease in Methanobrevibacter smithii

Abstract EN

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.