[Evaluation of practical usefulness of selected phenotypic and genotypic markers for pathogenicity of enterotoxic and entero-hemorrhagic strains of E.coli. ].
This study included a description of enterotoxic and verocytotoxic activity of thirty strains of E. coli and their ability to produce beta-haemolysis in a ram blood medium. Enterotoxic and verocytoxic activity was determined by using RPLA test. The synthesis of enterotoxin LT was observed in 10 strains and the production of E. coli shiga toxins type 1--Stx1 (1 strain) or type 2 (2 strains) was observed in 3 strains of serotype O157: H7. The beta-haemolytic characteristics in vitro were demonstrated by 17 strains (57%) isolated from pigs. Among them 16 (94%) were found to possess the genes that determine the enterotoxins or enterotoxins and E. coli shiga toxin Stx2v synthesis. Using the PCR technique, 21 strains (70%) were found to possess the genetic determinants of enterotoxins LT, STa and/or STb synthesis or enterotoxins and E. coli shiga toxin Stx2v synthesis. Further genetic study showed that the strains possessed the genes elt and estB were predominant (33%) among the toxic strains of E. coli isolated from piglets and calves.
Katedra Immunologii i Mikrobiologii Akademii Rolniczej w Szczecinie.
Jolanta
J
Karakulska
D000818:Animals; D001427:Bacterial Toxins / Q000096:biosynthesis*; D002417:Cattle; D004768:Enterotoxins / Q000096:biosynthesis*; D004926:Escherichia coli / Q000145:classification / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity*; D005838:Genotype; D010641:Phenotype; D013045:Species Specificity; D013552:Swine
D001427:Bacterial Toxins; D004768:Enterotoxins