Identification of ancillary fim genes affecting fimA expression in Salmonella typhimurium.
Regulation of the gene, fimA, encoding the major fimbrial subunit of S. typhimurium S6704 was examined by using a lambda fimA-lacZ lysogen. Transformation of the lambda fimA-lacZ lysogen with various derivatives of the recombinant plasmid that encodes type 1 fimbrial expression, pISF101, indicated that two regions of this plasmid alter beta-galactosidase production. One plasmid is a deletion resulting in the loss of a 28-kDa polypeptide downstream of fimA, while the other plasmid encodes a 24- and a 27-kDa polypeptide. Northern (RNA) blot analyses indicated that the steady-state fimA mRNA levels of these transformants were high. In addition, phenotypic expression of type 1 fimbriae by agar-grown cultures is observed only in those transformants bearing plasmids which show increased beta-galactosidase and fimA mRNA levels.
Department of Microbiology, University of Iowa College of Medicine, Iowa City 52242.
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D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics*; D001483:Base Sequence; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics*; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000096:biosynthesis; D011993:Recombinant Fusion Proteins; D012486:Salmonella typhimurium / Q000235:genetics*; D014170:Transformation, Genetic; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D008565:Membrane Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; C063055:fimbrillin; D036781:Fimbriae Proteins; D001616:beta-Galactosidase