Amuc_1102 from Akkermansia muciniphila adopts an immunoglobulin-like fold related to archaeal type IV pilus

Akkermansia muciniphila is a kind of beneficial microorganism colonized in the human gut. A. muciniphila is closely related to human intestinal health and has a good effect on diseases related to intestinal metabolism. The proteins encoded by the Amuc_1098-Amuc_1102 gene cluster, which are related to the formation and assembly of the pilus, are highly expressed in the membrane protein components of A. muciniphila. In this paper, we report the crystal structure of Amuc_1102 at a resolution of 1.75 angstrom, which adopts an immunoglobulin (Ig)-like fold. Amuc_1102 shares a similar fold to three archaeal proteins related to type IV pilus (T4P)-like structure, Pilin, FlaF, and FlaG, indicating a similar function. Amuc_1102 exists as a trimer both in the crystal structure and in solution, which differs from the assemblies of Pilin, FlaF, and FlaG. This study provides a structural basis for the elucidation of the T4P formation of A. muciniphila. (c) 2021 Elsevier Inc. All rights reserved.

Automated summary

Akkermansia muciniphila is a beneficial microorganism in the human gut that is closely related to intestinal health, with membrane proteins encoding proteins related to pilus formation. The crystal structure of Amuc_1102 reveals an immunoglobulin (Ig)-like fold and trimeric assembly, providing insights into type IV pilus formation in A. muciniphila.