A carboxy-terminal domain of Tir from enterohemorrhagic Escherichia coli O157 : H7 (EHEC O157 : H7) required for efficient type III secretion

摘要

The type III secreted protein Tir from Enterohemorrhagic Escherichia coli (EHEC O157:H7) plays a central role in adherence and pedestal formation during infection. Little is known about how Tir domains outside of the amino-terminus contribute to efficient Tir secretion and translocation. We found a 6 amino acid (519-524) carboxy-terminal region which was required for efficient Tir secretion and translocation. Interestingly, EHEC O157:H7 TirDelta519-524 was efficiently secreted when expressed in the related pathogen enteropathogenic E. coli. These data suggest that this region may play a role in maintaining EHEC O157:H7 Tir in a secretion-competent conformation. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.