Gal-Gal Binding and Hemolysin Phenotypes and Genotypes Associated with Uropathogenic Escherichia coli

• Published in: The New England journal of medicine Vol. 313; no. 7; pp. 414 - 420
• Main Authors: O'Hanley, Peter, Low, David, Romero, Irevis, Lark, David, Vosti, Kenneth, Falkow, Stanley, Schoolnik, Gary
• Format: Journal Article
• Language: English
• Published: Boston, MA Massachusetts Medical Society 15.08.1985
• Subjects: Adhesins; Adhesiveness; Bacteriology; Bacteriuria; Bacteriuria - microbiology; Biological and medical sciences; Cistrons; Colicins - biosynthesis; Colonization; Cystitis; Cystitis - microbiology; DNA probes; DNA, Bacterial - analysis; Epithelium - microbiology; Escherichia coli; Escherichia coli - classification; Escherichia coli - genetics; Escherichia coli - pathogenicity; Escherichia coli Infections - microbiology; Feces - microbiology; Female; Fimbriae, Bacterial - physiology; Fundamental and applied biological sciences. Psychology; Genomes; Genotypes; Hemagglutination; Hemolysin Proteins - biosynthesis; Hemolysin Proteins - genetics; Homology; Humans; Hybridization; Microbiology; Nucleic Acid Hybridization; Nucleotide sequence; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Phenotype; Pyelonephritis; Pyelonephritis - microbiology; Serotyping; Strains (organisms); Urinary Tract Infections - microbiology; Urine; Virulence; Urinary system disease; Gene product; Determinant; Escherichia coli; Virulence; Colicin V; Genotype; Homology; Molecular interaction; Gene organization; Adhesion; Proteins; Toxin; Phenotype; Pyelonephritis; Production; Pathogen strain; Bacteria; Escherichieae; Hemolysin; Clinical isolate; Comparative study; Enterobacteriaceae
• ISSN: 0028-4793; 1533-4406
• DOI: 10.1056/NEJM198508153130704

To determine whether uropathogenic strains of Escherichia coli exhibit a distinctive constellation of phenotypes, we examined 44 urinary isolates from women with radiologically normal urinary tracts and pyelonephritis, cystitis, or asymptomatic bacteriuria and 73 fecal isolates from healthy control subjects. The strains were characterized by their O serogroup, by their binding specificity (as determined by adhesins), and by their production of hemolysin and colicin V. In addition, the strains were assessed for homologous gene sequences by means of DNA-hybridization probes prepared from cistrons that encode hemolysin and the Gal-Gal binding adhesin — two determinants of virulence, which cause tissue injury and promote bacterial colonization of uroepithelia, respectively. In contrast to most isolates from normal feces and from the urine of patients with asymptomatic bacteriuria, pyelonephritis strains belong to a small number of O serogroups; all express the Gal-Gal binding adhesin and 75 per cent are hemolytic. A gene probe for the Gal-Gal binding adhesin, derived from the chromosome of one strain from a patient with pyelonephritis, hybridized with the DNA of all other pyelonephritis strains. The probe for the hemolysin gene hybridized with DNA from all other hemolytic strains. These data indicate that most cases of pyelonephritis are due to a small number of pathogenic clones that express critical determinants of virulence, and that the nucleotide sequences for hemolysin and the Gal-Gal binding adhesin in heterologous strains share homology. We are tempted to speculate that the gene products of these shared regions of the genome might form the basis for a vaccine against pyelonephritis. (N Engl J Med 1985; 313:414–20.) Escherichia coli is the most common bacterial species isolated from endogenous infections of the female urinary tract. 1 Uropathogenic strains usually originate in the colon. From the stool they are inoculated onto the vaginal introitus and periurethral region. 2 Colonization of uroepithelia may ensue, leading to bacteriuria. In some patients with bacteriuria mucosal invasion, inflammation, and cell death result in cystitis and pyelonephritis. Accordingly, infections of the urinary tract may be viewed as the culmination of a sequence of events mediated by specific determinants of microbial pathogenicity. It follows that uropathogenic E. coli may not merely be derived from the most prevalent . . .