The plasmid-encoded Yop2b protein of Yersinia pseudotuberculosis is a virulence determinant regulated by calcium and temperature at the level of transcription.
The basic Yop2b protein, encoded by the virulence plasmid pIBI of Yersinia pseudotuberculosis, is produced under Ca2+-deficient conditions. A mutant deleted for the entire yopH gene, which encodes the Yop2b protein, was found to be avirulent. Virulence could be restored by trans-complementation. The DNA-sequence of yopH predicted a 50 737 D polypeptide lacking a typical signal peptide. Transcription of yopH is regulated by both temperature and Ca2+-concentration. Mutations within the region of the virulence plasmid known to be involved in regulating gene expression in response to Ca2+ abolished transcription of yopH. Other temperature-sensitive mutations in the Ca2+-regulatory locus showed a high level of transcription regardless of Ca2+-concentration. These responses were similar to those of the yopE gene. The promoter region of the yopE and yopH genes were compared and four conserved motifs identified.
Bölin
I
I
Department of Cell Biology and Microbiology, National Defence Research Institute, Umeå, Sweden.
Wolf-Watz
H
H
D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002118:Calcium / Q000494:pharmacology*; D004262:DNA Restriction Enzymes; D005796:Genes / Q000187:drug effects; D005798:Genes, Bacterial / Q000187:drug effects; D008969:Molecular Sequence Data; D009154:Mutation; D009710:Nucleotide Mapping; D010957:Plasmids / Q000187:drug effects; D013696:Temperature; D014158:Transcription, Genetic / Q000187:drug effects; D014774:Virulence; D015011:Yersinia pseudotuberculosis / Q000235:genetics* / Q000472:pathogenicity
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; C056187:Yop2b (Yersinia); D004262:DNA Restriction Enzymes; D002118:Calcium