title: Microarray analysis of the Bacillus subtilis K-state: genome-wide expression changes dependent on ComK.
abstract: In Bacillus subtilis, the competence transcription factor ComK activates its own transcription as well as the transcription of genes that encode DNA transport proteins. ComK is expressed in about 10% of the cells in a culture grown to competence. Using DNA microarrays representing approximately 95% of the protein-coding open reading frames in B. subtilis, we compared the expression profiles of wild-type and comK strains, as well as of a mecA mutant (which produces active ComK in all the cells of the population) and a comK mecA double mutant. In these comparisons, we identified at least 165 genes that are upregulated by ComK and relatively few that are downregulated. The use of reporter fusions has confirmed these results for several genes. Many of the ComK-regulated genes are organized in clusters or operons, and 23 of these clusters are preceded by apparent ComK-box promoter motifs. In addition to those required for DNA uptake, other genes that are upregulated in the presence of ComK are probably involved in DNA repair and in the uptake and utilization of nutritional sources. From this and previous work, we conclude that the ComK regulon defines a growth-arrested state, distinct from sporulation, of which competence for genetic transformation is but one notable feature. We suggest that this is a unique adaptation to stress and that it be termed the 'K-state'.
authors.affiliation: Novozymes Biotech, Inc., Davis, CA 95616, USA.
authors.forename: Randy M
authors.initials: RM
authors.lastname: Berka
authors.forename: Jeanette
authors.initials: J
authors.lastname: Hahn
authors.forename: Mark
authors.initials: M
authors.lastname: Albano
authors.forename: Irena
authors.initials: I
authors.lastname: Draskovic
authors.forename: Marjan
authors.initials: M
authors.lastname: Persuh
authors.forename: Xianju
authors.initials: X
authors.lastname: Cui
authors.forename: Alan
authors.initials: A
authors.lastname: Sloma
authors.forename: William
authors.initials: W
authors.lastname: Widner
authors.forename: David
authors.initials: D
authors.lastname: Dubnau
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D016680:Genome, Bacterial; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014169:Transformation, Bacterial
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D014157:Transcription Factors; C087449:comK protein, Bacillus subtilis