Identification of CesT, a chaperone for the type III secretion of Tir in enteropathogenic Escherichia coli.

摘要: The locus of enterocyte effacement enteropathogenic Escherichia coli encodes a type III secretion system, an outer membrane protein adhesin (intimin, the product eae ) and Tir, translocated that becomes host cell receptor for intimin. Many secreted proteins require chaperones, which function to stabilize proteins, prevent inappropriate protein–protein interactions aid in secretion. An open reading frame located between tir eae, previously named orfU, was predicted encode with partial similarity Yersinia SycH chaperone. We examined potential orfU gene serve as chaperone Tir. encoded 15 kDa cytoplasmic specifically interacted Tir demonstrated by yeast two-hybrid assay, column binding coimmunoprecipitation experiments. mutant defective attaching–effacing lesion formation secretion, but unaffected expression other virulence factors. OrfU appeared levels cytoplasm, not absolutely necessary Based upon physical similarities, phenotypic characteristics interaction is redesignated cesT E. T ir.