Operon structure and gene expression of the espJ--tccP locus of enterohaemorrhagic Escherichia coli O157:H7.
In this study, we investigated the genetic organisation and expression of the espJ--tccP locus of enterohaemorrhagic Escherichia coli (EHEC O157:H7), which encodes the type III secretion system effector proteins EspJ and TccP. Using flow cytometry and fluorescence microscopy, we found that espJ and tccP constitute an operon, whose expression in vitro is affected by the composition of the medium and environmental signals such as temperature, pH, osmolarity and O(2) pressure. Moreover, expression of the espJ--tccP operon is not regulated by Ler, a LEE-encoded transcriptional regulator, but by an as yet unidentified regulatory system(s).
Garmendia
Junkal
J
Centre for Molecular Microbiology and Infection, Department of Biological Sciences, Imperial College London, London SW7 2AZ, UK.
Frankel
Gad
G
D019453:Escherichia coli O157 / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000502:physiology; D005434:Flow Cytometry; D015964:Gene Expression Regulation, Bacterial; D023061:Gene Order; D006863:Hydrogen-Ion Concentration; D008856:Microscopy, Fluorescence; D009876:Operon; D009997:Osmotic Pressure; D010100:Oxygen; D011401:Promoter Regions, Genetic; D015534:Trans-Activators / Q000502:physiology
D029968:Escherichia coli Proteins; C497366:EspJ protein, E coli; C465556:Ler protein, E coli; D015534:Trans-Activators; C505370:tccP protein, E coli; D010100:Oxygen