title: Identification of a mutant locus that bypasses the BsgA protease requirement for social development in Myxococcus xanthus.
abstract: The BsgA protease is required for the earliest morphological changes observed in Myxococcus xanthus development. We hypothesize that the BsgA protease is required to cleave an inhibitor of the developmental program, and isolation of genetic bypass suppressors of a bsgA mutant was used to identify signaling components controlling development downstream of the BsgA protease. Strain M955 was created by transposon mutagenesis of a bsgA mutant followed by screening for strains that could develop despite the absence of the BsgA protease. Strain M955 was able to aggregate, form fruiting bodies, and partially restored the production of viable spores in comparison to the parental bsgA mutant. The bsgA Tn5Ω955 strain partially restored developmental expression to a subset of genes normally induced during development, and expressed one developmentally induced fusion at higher amounts during vegetative growth in comparison to wild-type cells. The transposon in strain M955 was localized to a Ribonuclease D homolog that appears to exist in an operon with a downstream aminopeptidase-encoding gene. The identification of a third distinct bypass suppressor of the BsgA protease suggests that the BsgA protease may regulate a potentially complex pathway during the initiation of the M. xanthus developmental program.
authors: California Northstate University College of Medicine, 9700 West Taron Drive, Elk Grove, CA 95757, USA john.cusick@cnsu.edu.
authors: John K
authors: JK
authors: Cusick
authors: Department of Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
authors: Elizabeth
authors: E
authors: Hager
authors: Department of Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
authors: Ronald E
authors: RE
authors: Gill
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D004252:DNA Mutational Analysis; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D010450:Endopeptidases / Q000172:deficiency / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D055786:Gene Knockout Techniques; D053263:Gene Regulatory Networks; D056426:Genetic Loci; D056265:Microbial Interactions; D050296:Microbial Viability; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D016941:Myxococcus xanthus / Q000235:genetics* / Q000254:growth & development*; D013171:Spores, Bacterial / Q000254:growth & development; D013489:Suppression, Genetic
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D010450:Endopeptidases; C082110:BsgA protein, Myxococcus xanthus
keywords: biofilm; cell communication; genetic bypass suppressor