Regulation of the Porphyromonas gingivalis fimA (Fimbrillin) gene.
In common with many bacterial virulence genes, the fimbrillin (fimA) gene of Porphyromonas gingivalis is modulated in response to environmental fluctuation. The trans-acting components that comprise the regulatory system for transcriptional activity of the fimA gene in P. gingivalis were investigated. Three major proteins were found to bind to the upstream region of the fimA promoter. One of these proteins was fimbrillin itself, and the other two were a major arginine protease (Rgp) and lysine protease (Kgp). Production of these proteins was necessary for maximal fimA transcription. An exogenous fimA promoter-lacZ reporter was inactive when introduced into a strain of P. gingivalis carrying a mutation in the indigenous fimA gene. Furthermore, fimA mRNA levels were significantly decreased in rgp and kgp mutant strains. These data indicate that P. gingivalis has evolved multiple levels of control of fimbrial gene expression to enhance its survival in hostile environments.
Xie
H
H
School of Dentistry, Meharry Medical College, Nashville, Tennessee 37208, USA. hxie@mail.mmc.edu
Chung
W O
WO
Park
Y
Y
Lamont
R J
RJ
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D036781:Fimbriae Proteins; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D009154:Mutation; D016966:Porphyromonas gingivalis / Q000235:genetics* / Q000472:pathogenicity; D011401:Promoter Regions, Genetic; D014158:Transcription, Genetic; D014774:Virulence
D001426:Bacterial Proteins; C063055:fimbrillin; D036781:Fimbriae Proteins