title: Phenotypic and genotypic analysis of pathogenicEscherichia colivirulence genes recovered from Riyadh, Saudi Arabia.
abstract: The current study was carried out to evaluate the phenotypic and genotypic characterization of avian pathogenicEscherichia colirecovered from Riyadh, Saudi Arabia. During the period of 10th February-30th May 2015, 70E. colistrains were isolated from chicken farms located in Riyadh, Saudi Arabia. All strains were tested phenotypically by standard microbiological techniques, serotyped and the virulence genes of such strains were detected by polymerase chain reaction (PCR). Most of the recovered strains from chickens belonged to serotype O111:K58 25 strains (35.7%), followed by serotype O157:H7 13 strains (18.57%), followed by serotype O114:K90 10 strains (14.29%), then serotype O126:K71 9 strains (12.9%), serotype O78:K80 8 strains (11.43%) and in lower percentage serotype O114:K90 and O119:K69 5 strains (7.14%). The virulence genotyping ofE. coliisolates recovered from broilers revealed the presence of theuidAgene in all the field isolates (6 serovars) examined in an incidence of 100%, as well as thecvaCgene was also present in all field isolates (6 serovars), while theiutAgene and theissgene were detected in 5 out of 6 field serovars in an incidence of 81.43% and 64.29%, respectively. Phenotypical examination of the other virulence factors revealed that 65 isolates were hemolytic (92.9%), as well as 15 isolates (21.42%) were positive for enterotoxin production. Meanwhile, 21 isolates (30%) were positive for verotoxin production, 58 isolates (82.86%) for the invasiveness and 31 isolates (44.29%) for Congo red binding activities of the examined serotypes.
authors.affiliation: Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Abdullah A
authors.initials: AA
authors.lastname: Al-Arfaj
authors.affiliation: Department of Microbiology and Immunology, College of Pharmacy, AL Azhar University, Cairo, Egypt.
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Ali
authors.affiliation: Department of Health Science, College of Applied Studies and Community Service, King Saud University, P.O. Box 22459, Riyadh 11495, Saudi Arabia; Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, P.O. 2446, Cairo 14242, Giza, Egypt.
authors.forename: Ashgan M
authors.initials: AM
authors.lastname: Hessain
authors.affiliation: Department of Plant Production, College of Food and Agriculture Science, King Saud University, P.O. Box 2466, Riyadh 11451, Saudi Arabia.
authors.forename: Adel M
authors.initials: AM
authors.lastname: Zakri
authors.affiliation: Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Turki M
authors.initials: TM
authors.lastname: Dawoud
authors.affiliation: Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Khalid S
authors.initials: KS
authors.lastname: Al-Maary
authors.affiliation: Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia; Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, P.O. 2446, Cairo 14242, Giza, Egypt.
authors.forename: Ihab M
authors.initials: IM
authors.lastname: Moussa
keywords: Avian pathogenic; Escherichia coli; PCR; Serotyping; Virulence factors