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Adaptor-mediated Lon proteolysis restricts Bacillus subtilis hyperflagellation.

ABSTRACT: The Lon AAA+ protease is a highly conserved intracellular protease that is considered an anticancer target in eukaryotic cells and a crucial virulence regulator in bacteria. Lon degrades both damaged, misfolded proteins and specific native regulators, but how Lon discriminates among a large pool of candidate targets remains unclear. Here we report that Bacillus subtilis LonA specifically degrades the master regulator of flagellar biosynthesis SwrA governed by the adaptor protein swarming motility inhibitor A (SmiA). SmiA-dependent LonA proteolysis is abrogated upon microbe-substrate contact causing SwrA protein levels to increase and elevate flagellar density above a critical threshold for swarming motility atop solid surfaces. Surface contact-dependent cellular differentiation in bacteria is rapid, and regulated proteolysis may be a general mechanism of transducing surface stimuli.

SUBMITTER: Mukherjee S

PROVIDER: S-EPMC4291670 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Adaptor-mediated Lon proteolysis restricts Bacillus subtilis hyperflagellation.

Mukherjee Sampriti S Bree Anna C AC Liu Jing J Patrick Joyce E JE Chien Peter P Kearns Daniel B DB

Proceedings of the National Academy of Sciences of the United States of America 20141223 1

The Lon AAA+ protease is a highly conserved intracellular protease that is considered an anticancer target in eukaryotic cells and a crucial virulence regulator in bacteria. Lon degrades both damaged, misfolded proteins and specific native regulators, but how Lon discriminates among a large pool of candidate targets remains unclear. Here we report that Bacillus subtilis LonA specifically degrades the master regulator of flagellar biosynthesis SwrA governed by the adaptor protein swarming motilit ...[more]

PMID: 25538299

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2022-10-15 | PXD032931 | Pride

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