title: Organization and evolution of the cotG and cotH genes of Bacillus subtilis.
abstract: The cotG and cotH genes of Bacillus subtilis encode two previously characterized spore coat proteins. The two genes are adjacent on the chromosome and divergently transcribed by σ(K), a sporulation-specific σ factor of the RNA polymerase. We report evidence that the cotH promoter maps 812 bp upstream of the beginning of its coding region and that the divergent cotG gene is entirely contained between the promoter and the coding part of cotH. A bioinformatic analysis of all entirely sequenced prokaryotic genomes showed that such chromosomal organization is not common in spore-forming bacilli. Indeed, CotG is present only in B. subtilis, B. amyloliquefaciens, and B. atrophaeus and in two Geobacillus strains. When present, cotG always encodes a modular protein composed of tandem repeats and is always close to but divergently transcribed with respect to cotH. Bioinformatic and phylogenic data suggest that such genomic organizations have a common evolutionary origin and that the modular structure of the extant cotG genes is the outcome of multiple rounds of gene elongation events of an ancestral minigene.
authors: Department of Structural and Functional Biology, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.
authors: Rosa
authors: R
authors: Giglio
authors: Renato
authors: R
authors: Fani
authors: Rachele
authors: R
authors: Isticato
authors: Maurilio
authors: M
authors: De Felice
authors: Ezio
authors: E
authors: Ricca
authors: Loredana
authors: L
authors: Baccigalupi
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000737:chemistry / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D019143:Evolution, Molecular; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D016415:Sequence Alignment; D013171:Spores, Bacterial / Q000737:chemistry / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; C101016:CotH protein, Bacillus subtilis; C091352:cotG protein, Bacillus subtilis