Open AccessThe Type 4 Pili of Enterohemorrhagic Escherichia coli O157:H7 Are Multipurpose Structures with Pathogenic Attributes
Author(s) -
Juan Xicohtencatl-Cortés,
Valério Monteiro-Neto,
Zeus Saldaña,
Maria A. Ledesma,
José L. Puente,
Jorge A. Girón
Publication year - 2009
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.01306-08
Subject(s) - biology , pilus , escherichia coli , fimbriae proteins , microbiology and biotechnology , escherichia coli proteins , pathogenic escherichia coli , enterobacteriaceae , fimbria , escherichia , genetics , gene
EnterohemorrhagicEscherichia coli (EHEC) O157:H7 produces long bundles of polar type 4 pili (T4P) called HCP (forh emorrhagicc olip ili) that form physical bridges between bacteria associating with human and animal epithelial cells. Here, we sought to further investigate whether HCP possessed other pathogenicity attributes associated with T4P production. Comparative studies performed with wild-type EHEC EDL933 and an isogenichcpA mutant revealed that HCP play different roles in the biology of this organism. We found that in addition to promoting bacterial attachment to host cells, HCP mediate (i) invasion of epithelial cells, (ii) hemagglutination of rabbit erythrocytes, (iii) interbacterial connections conducive to biofilm formation, (iv) specific binding to host extracellular matrix proteins laminin and fibronectin but not collagen, and (v) twitching motility. Nonadherent laboratoryE. coli strain HB101 complemented withhcpABC genes on plasmid pJX22, which specifies for HCP overproduction in EDL933, became hyperadherent and invasive and produced a thick biofilm, suggesting that the presence of HCP confers HB101(pJX22) new attributes otherwise not exhibited by HB101. Analogous to other bacteria in which T4P are involved in the pathogenesis of several infectious diseases, our data strongly suggest that HCP display multiple functions that may contribute to EHEC colonization of different hosts and to virulence, survival, and transmission of this food-borne pathogen.