J. Bacteriol., Jun 1996, 3113-3118, Vol 178, No. 11
Copyright © 1996, American Society for Microbiology

Role of FlgM in sigma D-dependent gene expression in Bacillus subtilis

T Caramori, D Barilla, C Nessi, L Sacchi and A Galizzi
Dipartimento di Genetica e Microbiologia "A. Buzzati-Traverso", Universita degli Studi, Pavia, Italy.

The alternative sigma factor sigma D directs transcription of a number of genes involved in chemotaxis, motility, and autolysis in Bacillus subtilis (sigmaD regulon). The activity of SigD is probably in contrast to that of FlgM, which acts as an antisigma factor and is responsible for the coupling of late flagellar gene expression to the assembly of the hook-basal body complex. We have characterized the effects of an in- frame deletion mutation of flgM. By transcriptional fusions to lacZ, we have shown that in FlgM-depleted strains there is a 10-fold increase in transcription from three different sigmaD-dependent promoters, i.e., Phag, PmotAB, and PfliDST. The number of flagellar filaments was only slightly increased by the flgM mutation. Overexpression of FlgM from a multicopy plasmid under control of the isopropyl-beta-D- thiogalactopyranoside-inducible spac promoter drastically reduced the level of transcription from the hag promoter. On the basis of these results, we conclude that, as in Salmonella typhimurium, FlgM inhibits the activity of SigD, but an additional element is involved in determining the number of flagellar filaments.

This article has been cited by other articles:

• Wolgemuth, C. W. (2008). Collective Swimming and the Dynamics of Bacterial Turbulence. Biophys. J 95: 1564-1574 [Abstract] [Full Text]  
• Kearns, D. B., Losick, R. (2005). Cell population heterogeneity during growth of Bacillus subtilis. Genes Dev. 19: 3083-3094 [Abstract] [Full Text]  
• Frisk, A., Jyot, J., Arora, S. K., Ramphal, R. (2002). Identification and Functional Characterization of flgM, a Gene Encoding the Anti-Sigma 28 Factor in Pseudomonas aeruginosa. J. Bacteriol. 184: 1514-1521 [Abstract] [Full Text]  
• West, J. T., Estacio, W., Márquez-Magaña, L. (2000). Relative Roles of the fla/che PA, PD-3, and PsigD Promoters in Regulating Motility and sigD Expression in Bacillus subtilis. J. Bacteriol. 182: 4841-4848 [Abstract] [Full Text]  
• Mirel, D. B., Estacio, W. F., Mathieu, M., Olmsted, E., Ramirez, J., Márquez-Magaña, L. M. (2000). Environmental Regulation of Bacillus subtilis sigma D-Dependent Gene Expression. J. Bacteriol. 182: 3055-3062 [Abstract] [Full Text]  
• Ju, J., Mitchell, T., Peters, H. III, Haldenwang, W. G. (1999). Sigma Factor Displacement from RNA Polymerase during Bacillus subtilis Sporulation. J. Bacteriol. 181: 4969-4977 [Abstract] [Full Text]  
• Yang, D.-H., von Kalckreuth, J., Allmansberger, R. (1999). Synthesis of the sigma D Protein Is Not Sufficient To Trigger Expression of Motility Functions in Bacillus subtilis. J. Bacteriol. 181: 2942-2946 [Abstract] [Full Text]  
• Bertero, M. G., Gonzales, B., Tarricone, C., Ceciliani, F., Galizzi, A. (1999). Overproduction and Characterization of the Bacillus subtilis Anti-sigma Factor FlgM. J. Biol. Chem. 274: 12103-12107 [Abstract] [Full Text]  
• Liu, J., Zuber, P. (1998). A Molecular Switch Controlling Competence and Motility: Competence Regulatory Factors ComS, MecA, and ComK Control sigma D-Dependent Gene Expression in Bacillus subtilis. J. Bacteriol. 180: 4243-4251 [Abstract] [Full Text]  
• Estacio, W., Anna-Arriola, S. S., Adedipe, M., Márquez-Magaña, L. M. (1998). Dual Promoters Are Responsible for Transcription Initiation of the fla/che Operon in Bacillus subtilis. J. Bacteriol. 180: 3548-3555 [Abstract] [Full Text]