Organization and temporal expression of a flagellar basal body gene in Caulobacter crescentus.
AUTOR(ES)
Hahnenberger, K M
RESUMO
Caulobacter crescentus assembles a single polar flagellum at a defined time in the cell cycle. The protein components of the flagellar hook and filament are synthesized just prior to their assembly. We demonstrated that the expression of a gene, flaD, that is involved in the formation of the flagellar basal body is under temporal control and is transcribed relatively early in the cell cycle, before the hook and flagellin genes are transcribed. Thus, the order of flagellar gene transcription reflects the order of assembly of the protein components. A mutation in the flaD gene results in the assembly of a partial basal body which is missing the outermost P and L rings as well as the external hook and filament (K.M. Hahnenberger and L. Shapiro, J. Mol. Biol. 194:91-103, 1987). The flaD gene was cloned and characterized by nucleotide sequencing and S1 nuclease protection assays. In contrast to the protein components of the hook and filament, the protein encoded by the flaD gene contains a hydrophobic leader peptide. The predicted amino acid sequence of the leader peptide of flaD is very similar to the leader peptide of the flagellar basal body P ring of Salmonella typhimurium (M. Homma, Y. Komeda, T. Iino, and R.M. Macnab, J. Bacteriol. 169:1493-1498, 1987).
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=211417Documentos Relacionados
- Flagellar hook and basal complex of Caulobacter crescentus.
- A mutation that uncouples flagellum assembly from transcription alters the temporal pattern of flagellar gene expression in Caulobacter crescentus.
- Reconstitution and purification of flagellar filaments from Caulobacter crescentus.
- Isolation and expression of cloned hook protein gene from Caulobacter crescentus.
- Circular organization of the DNA synthetic pathway in Caulobacter crescentus.