Bacillus subtilis Marburg 168 cells with disrupted
ugtP, which encodes UDP-glucosyltransferase involved in glucolipid synthesis, were bent and distended. In the
ugtP mutant cells, the extracytoplasmic function sigmas SigM, SigV and SigX, were found to be activated. Introduction of a disrupted allele of
sigM into the
ugtP strain caused even more abnormal morphology, with cells taking on a balloon-like shape; growth of these cells in LB medium was hampered by addition of 1.5% NaCl. Addition of MgSO
4 or MnCl
2 suppressed the abnormal morphology. In
ugtP mutant cells the transcription of the
mreB operon from an upstream promoter in
maf (designated Pupstream
mreB) and P
mreBH was 4.3- and 2.3-fold higher, respectively, and localization of GFP-MreB was not in discrete dots (in an apparently helical pattern), but faint and in irregular clusters. GFP-MreB protein was reduced in the
ugtP mutant cells. We suggest that glucolipids are important for MreB isoforms to take on the configuration that appears as discrete dots and plays a role in shaping cells into straight rods.
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