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Ubiquitin-like protein involved in the proteasome pathway of Mycobacterium tuberculosis.

ABSTRACT: The protein modifier ubiquitin is a signal for proteasome-mediated degradation in eukaryotes. Proteasome-bearing prokaryotes have been thought to degrade proteins via a ubiquitin-independent pathway. We have identified a prokaryotic ubiquitin-like protein, Pup (Rv2111c), which was specifically conjugated to proteasome substrates in the pathogen Mycobacterium tuberculosis. Pupylation occurred on lysines and required proteasome accessory factor A (PafA). In a pafA mutant, pupylated proteins were absent and substrates accumulated, thereby connecting pupylation with degradation. Although analogous to ubiquitylation, pupylation appears to proceed by a different chemistry. Thus, like eukaryotes, bacteria may use a small-protein modifier to control protein stability.

SUBMITTER: Pearce MJ

PROVIDER: S-EPMC2698935 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Ubiquitin-like protein involved in the proteasome pathway of Mycobacterium tuberculosis.

Pearce Michael J MJ Mintseris Julian J Ferreyra Jessica J Gygi Steven P SP Darwin K Heran KH

Science (New York, N.Y.) 20081002 5904

The protein modifier ubiquitin is a signal for proteasome-mediated degradation in eukaryotes. Proteasome-bearing prokaryotes have been thought to degrade proteins via a ubiquitin-independent pathway. We have identified a prokaryotic ubiquitin-like protein, Pup (Rv2111c), which was specifically conjugated to proteasome substrates in the pathogen Mycobacterium tuberculosis. Pupylation occurred on lysines and required proteasome accessory factor A (PafA). In a pafA mutant, pupylated proteins were a ...[more]

PMID: 18832610

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