Open AccessCloning of the fliI gene from Rhodobacter sphaeroides WS8 by analysis of a transposon mutant with impaired motility
Author(s) -
Goodfellow Ian Gordon,
Pollitt Charles Edward,
Sockett Renee Elizabeth
Publication year - 1996
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1996.tb08416.x
Subject(s) - mutant , flagellin , rhodobacter sphaeroides , biology , transposable element , gene , microbiology and biotechnology , genetics , plasmid , flagellum , southern blot , bacteria
A transposon mutant of Rhodobacter sphaeroides WS8 was isolated that showed reduced swarming on soft agar plates. Liquid cultures of this mutant (M18) showed a low percentage of motile swimming cells in mid‐exponential phase and a low level of extracellular flagellin protein by Western blotting. M18 was complemented by a clone from a library of R. sphaeroides WS8 DNA, and restriction mapping of the site of TnphoA insertion in the mutant, coupled with DNA sequencing, showed that it had a defect in the fliI gene. To determine if a partly functional fliI gene was giving the low‐motility phenotype of M18, a drug resistance omega cartridge was inserted into the gene to give a complete null mutant. This null strain also produced a low percentage of motile cells. Possible reasons for this apparent fliI ‐independent flagellar formation are discussed.