title: O side chain deficiency enhances sensitivity of Escherichia coli to Shiga toxin 2-converting bacteriophages.
abstract: We investigated the relationship between expression of the O side chain of outer membrane lipopolysaccharide (LPS) and infection by a Shiga toxin 2 (Stx2)-converting phage in normal and benign strains of Escherichia coli. Of 19 wild-type E. coli strains isolated from the feces of healthy subjects, those with low-molecular-weight LPS showed markedly higher susceptibility to lytic and lysogenic infection by Stx2 phages than those with high-molecular-weight LPS. All lysogens produced infectious phage particles and Stx2. The Stx-negative E. coli O157:H7 strain ATCC43888 with an intact O side chain was found to be resistant to lysis by an Stx2 phage and lysogenic infection by a recombinant Stx2 phage, whereas a rfbE mutant deficient in the expression of the O side chain was readily infected by the phage and yielded stable lysogens. The evidence suggests that an O side chain deficiency leads to the creation of new pathotypes of Shiga toxin-producing E. coli (STEC) within the intestinal microflora.
authors.affiliation: Department of Bioscience, Graduate School of Science and Technology, Kobe University, Rokko-dai 1-1, Kobe, 657-8501, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Iguchi
authors.forename: Sunao
authors.initials: S
authors.lastname: Iyoda
authors.forename: Haruo
authors.initials: H
authors.lastname: Watanabe
authors.forename: Ro
authors.initials: R
authors.lastname: Osawa
mesh_terms: D002238:Carbohydrate Epimerases / Q000235:genetics; D003090:Coliphages / Q000235:genetics*; D004926:Escherichia coli / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000821:virology*; D005243:Feces / Q000382:microbiology; D006801:Humans; D008070:Lipopolysaccharides / Q000737:chemistry*; D008242:Lysogeny; D022641:Shiga Toxin 2 / Q000378:metabolism*; D000637:Transaminases / Q000235:genetics
chemical_list: D008070:Lipopolysaccharides; D022641:Shiga Toxin 2; D000637:Transaminases; D002238:Carbohydrate Epimerases; C061272:perosamine synthetase