A flagellar gene cluster from the oval spirochaete Treponema maltophilum

Citation
K. Heuner et al., A flagellar gene cluster from the oval spirochaete Treponema maltophilum, MICROBIO-UK, 146, 2000, pp. 497-507
Citations number
66
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Microbiology
Journal title
MICROBIOLOGY-UK
ISSN journal
1350-0872 → ACNP
Volume
146
Year of publication
2000
Part
2
Pages
497 - 507
Database
ISI
SICI code
1350-0872(200002)146:<497:AFGCFT>2.0.ZU;2-X
Abstract
A flagellar gene cluster from the oral spirochaete Treponema maltophilum AT CC 51939(T) was cloned, Sequence analysis revealed six putative ORFs, two o f which encode the flagellar subunit proteins FlaB2 (286 aa) and FlaB3 (285 aa). Northern blot analysis revealed two flagellin transcripts with the ex pected size of monocistronic mRNAs. Sequence analysis and primer extension experiments indicated that the transcription of the flaB2 gene is directed by a sigma(28)-like FliA factor. Using fliA and fliA(+) Escherichia coli K- 12 strains, it was shown that flaB(2) expression in E. coli required the si gma(28) factor using an initiation site identical to that in Treponema malt ophilum, Primer extension analysis revealed two transcriptional start sites 5' of the flaB3 gene, a strong promoter with a sigma(28)-like -10 promoter element and a weak promoter with a putative sigma(54) promoter consensus s equence. Downstream of flaB3, a putative fliD homologue was found, probably encoding the flagellar cap protein of Treponema maltophilum. Flagellin-gen e-specific DNA probes hybridized to all 13 Treponema strains investigated, whereas a fliD-specific DNA probe only hybridized to Treponema maltophilum, other treponemal group IV isolates and Treponema brennaborense.