The urease gene cluster of Vibrio parahaemolyticus does not influence the expression of the thermostable direct hemolysin (TDH) gene or the TDH-related hemolysin gene.
In order to investigate why the thermostable direct hemolysin (TDH) and the TDH-related hemolysin (TRH) of Vibrio parahaemolyticus are produced at low levels from urease-positive strains, the effect of the functional urease gene cluster of V. parahaemolyticus on the expression of the tdh and trh genes was examined. Transcriptional lacZ fusions with the tdh1, tdh2, trh1 and trh2 genes representing variants of the tdh and trh genes were integrated into the chromosome of an Escherichia coli strain and a urease-negative V. parahaemolyticus strain. The plasmid-borne urease gene cluster introduced and expressed in these constructs did not affect expression of any of the fusion genes. The amount of TDH produced from a Kanagawa phenomenon-positive V. parahaemolyticus did not change by introduction of the urease gene cluster either. It was concluded therefore that the urease gene cluster is not involved in the regulation of tdh and trh expression.
Graduate School of Medicine, Kyoto University, Kyoto, Kyoto 606-8501, Japan.
Yoshitsugu
Y
Nakaguchi
Jun
J
Okuda
Tetsuya
T
Iida
Mitsuaki
M
Nishibuchi
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D006460:Hemolysin Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D005810:Multigene Family; D010957:Plasmids; D014158:Transcription, Genetic; D014510:Urease / Q000096:biosynthesis / Q000235:genetics*; D014736:Vibrio parahaemolyticus / Q000201:enzymology* / Q000235:genetics*
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; C088609:thermostable direct hemolysin-related hemolysin protein, Vibrio parahaemolyticus; C068489:thermostable direct hemolysin; D014510:Urease