title: Transcription of the Bacillus subtilis gerK operon, which encodes a spore germinant receptor, and comparison with that of operons encoding other germinant receptors.
abstract: The gerA, gerB, and gerK operons, which encode germinant receptors in spores of Bacillus subtilis, were transcribed only in sporulation, and their mRNA levels peaked initially approximately 3 h before the initiation of accumulation of the spore's dipicolinic acid. After a rapid fall, levels of these mRNAs peaked again approximately 5 h later. In one wild-type strain (PS832), gerA mRNA was the most abundant, with levels of gerB and gerK mRNAs approximately 50% of that of gerA mRNA, whereas gerB mRNA was the most abundant in another wild-type strain (PY79). The synthesis of gerK mRNA in sporulation was abolished by loss of the forespore-specific RNA polymerase sigma factor, sigma(G), and induction of sigma(G) synthesis in vegetative cells led to synthesis of gerK mRNA. SpoVT, a regulator of sigma(G)-dependent gene expression, repressed gerK expression. The gerK promoter showed sequence similarities to sigma(G)-dependent promoters, and deletion of elements of this putative promoter abolished gerK expression in sporulation.
authors.affiliation: Department of Molecular, Microbial, and Structural Biology, University of Connecticut Health Center, Farmington, CT 06030-3305, USA.
authors.forename: Takao
authors.initials: T
authors.lastname: Igarashi
authors.forename: Peter
authors.initials: P
authors.lastname: Setlow
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics* / Q000502:physiology; D001426:Bacterial Proteins / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005838:Genotype; D007700:Kinetics; D009876:Operon; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics; D011956:Receptors, Cell Surface / Q000235:genetics*; D013171:Spores, Bacterial; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface