title: A new class of proteins regulating gene expression in enterobacteria.
abstract: YmoA and Hha are highly similar bacterial proteins downregulating gene expression in Yersinia enterocolitica and Escherichia coli, respectively. The phenotype of ymoA mutants evokes that of mutants affected in some histone-like proteins. This paper describes complementation of a ymoA mutation in Y. enterocolitica by the hha gene from E. coli. We show that YmoA and Hha are not only very similar proteins but that they are functionally interchangeable. Genetic experiments indicate that Hha can also stimulate transposition events in vivo. By Southern blot analysis we detected hha-homologous genes at least in Citrobacter diversus, Shigella flexneri, Shigella dysenteriae, Klebsiella pneumoniae and Salmonella typhimurium. We suggest that both YmoA and Hha belong to a new family of proteins downregulating gene expression in different enterobacteria.
authors.affiliation: Microbial Pathogenesis Unit, Université Catholique de Louvain, UCL 54.90, Brussels, Belgium.
authors.forename: A V
authors.initials: AV
authors.lastname: Mikulskis
authors.forename: G R
authors.initials: GR
authors.lastname: Cornelis
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D003227:Conjugation, Genetic; D004251:DNA Transposable Elements / Q000235:genetics; D004269:DNA, Bacterial / Q000302:isolation & purification; D004268:DNA-Binding Proteins; D004755:Enterobacteriaceae / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D009154:Mutation; D011993:Recombinant Fusion Proteins / Q000235:genetics; D014158:Transcription, Genetic / Q000235:genetics; D015008:Yersinia enterocolitica / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; C079210:YmoA protein, Yersinia enterocolitica; C079209:hha protein, E coli