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Crystal and solution structures of a prokaryotic M16B peptidase: an open and shut case.

ABSTRACT: The M16 family of zinc peptidases comprises a pair of homologous domains that form two halves of a "clam-shell" surrounding the active site. The M16A and M16C subfamilies form one class ("peptidasomes"): they degrade 30-70 residue peptides, and adopt both open and closed conformations. The eukaryotic M16B subfamily forms a second class ("processing proteases"): they adopt a single partly-open conformation that enables them to cleave signal sequences from larger proteins. Here, we report the solution and crystal structures of a prokaryotic M16B peptidase, and demonstrate that it has features of both classes: thus, it forms stable "open" homodimers in solution that resemble the processing proteases; but the clam-shell closes upon binding substrate, a feature of the M16A/C peptidasomes. Moreover, clam-shell closure is required for proteolytic activity. We predict that other prokaryotic M16B family members will form dimeric peptidasomes, and propose a model for the evolution of the M16 family.

SUBMITTER: Aleshin AE

PROVIDER: S-EPMC3615642 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Crystal and solution structures of a prokaryotic M16B peptidase: an open and shut case.

Aleshin Alexander E AE Gramatikova Svetlana S Hura Gregory L GL Bobkov Andrey A Strongin Alex Y AY Stec Boguslaw B Tainer John A JA Liddington Robert C RC Smith Jeffrey W JW

Structure (London, England : 1993) 20091101 11

The M16 family of zinc peptidases comprises a pair of homologous domains that form two halves of a "clam-shell" surrounding the active site. The M16A and M16C subfamilies form one class ("peptidasomes"): they degrade 30-70 residue peptides, and adopt both open and closed conformations. The eukaryotic M16B subfamily forms a second class ("processing proteases"): they adopt a single partly-open conformation that enables them to cleave signal sequences from larger proteins. Here, we report the solu ...[more]

PMID: 19913481

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Crystal and solution structures of a prokaryotic M16B peptidase: an open and shut case.

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Crystal and solution structures of a prokaryotic M16B peptidase: an open and shut case.

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