RRC ID 74376
著者 Kotaro Sano, Hiroaki Kobayashi, Hirotaka Chuta, Nozomi Matsuyoshi, Yuki Kato, Hiroshi Ogasawara
タイトル CsgI (YccT) Is a Novel Inhibitor of Curli Fimbriae Formation in Escherichia coli Preventing CsgA Polymerization and Curli Gene Expression
ジャーナル International Journal of Molecular Sciences
Abstract Curli fimbriae are amyloids—found in bacteria (Escherichia coli)—that are involved in solid-surface adhesion and bacterial aggregation during biofilm formation. The curli protein CsgA is coded by a csgBAC operon gene, and the transcription factor CsgD is essential to induce its curli protein expression. However, the complete mechanism underlying curli fimbriae formation requires elucidation. Herein, we noted that curli fimbriae formation was inhibited by yccT—i.e., a gene that encodes a periplasmic protein of unknown function regulated by CsgD. Furthermore, curli fimbriae formation was strongly repressed by CsgD overexpression caused by a multicopy plasmid in BW25113—the non-cellulose-producing strain. YccT deficiency prevented these CsgD effects. YccT overexpression led to intracellular YccT accumulation and reduced CsgA expression. These effects were addressed by deleting the N-terminal signal peptide of YccT. Localization, gene expression, and phenotypic analyses revealed that YccT-dependent inhibition of curli fimbriae formation and curli protein expression was mediated by the two-component regulatory system EnvZ/OmpR. Purified YccT inhibited CsgA polymerization; however, no intracytoplasmic interaction between YccT and CsgA was detected. Thus, YccT—renamed CsgI (curli synthesis inhibitor)—is a novel inhibitor of curli fimbriae formation and has a dual role as an OmpR phosphorylation modulator and CsgA polymerization inhibitor.
巻・号 24
ページ 4357
公開日 2023-2-22
DOI 10.3390/ijms24054357
PMID 36901788
PMC PMC10002515
MeSH Bacterial Adhesion / genetics Bacterial Proteins / metabolism Biofilms Escherichia coli* / metabolism Escherichia coli Proteins* / metabolism Gene Expression Gene Expression Regulation, Bacterial Polymerization Trans-Activators / metabolism
IF 4.556
リソース情報
原核生物(大腸菌) ME9062(BW25113)