Isolation and identification of Escherichia coli O157:H7 using different detection methods and molecular determination by multiplex PCR and RAPD.
Escherichia coli O157:H7 is recognized as a significant food-borne pathogen, so rapid identification is important for food hygiene management and prompt epidemiological investigations. The limited prevalence data on Shiga toxin-producing E. coli (STEC) and E. coli O157:H7 in foods and animals in Korea made an assessment of the risks difficult, and the options for management and control unclear. The prevalence of the organisms was examined by newly developed kit-E. coli O157:H7 Rapid kit. For the isolation of E. coli O157:H7, conventional culture, immunomagnetic separation, and E. coli O157:H7 Rapid kit were applied, and multiplex PCR and randomly amplified polymorphic DNA (RAPD) were performed for the molecular determination. There was high molecular relatedness among 11 Korean isolates and 17 U.S. strains at 63% level. Additionally, distinct differentiation between pig and cattle isolates was determined. It implied that RAPD had a capacity to distinguish strains with different sources, however it could not discriminate among isolates according to their differences in the degree of virulence. In antimicrobial susceptibility tests, 45.5% of isolates showed antibiotic resistance to two or more antibiotics. Unlike the isolates from other countries, domestic isolates of E. coli O157:H7 was mainly resistant to ampicillin and tetracyclines. In summary, the application of E. coli O157:H7 Rapid kit may be useful to detect E. coli O157:H7 due to its sensitivity and convenience. Moreover, combinational analysis of multiplex PCR together with RAPD can aid to survey the characteristics of isolates.
Kim
Ji-Yeon
JY
Department of Animal Disease Diagnosis, National Veterinary Research and Quarantine Service, Anyang 430-824, Korea.
Kim
So-Hyun
SH
Kwon
Nam-Hoon
NH
Bae
Won-Ki
WK
Lim
Ji-Youn
JY
Koo
Hye-Cheong
HC
Kim
Jun-Man
JM
Noh
Kyoung-Min
KM
Jung
Woo-Kyung
WK
Park
Kun-Taek
KT
Park
Yong-Ho
YH
D000003:Abattoirs; D018829:Adhesins, Bacterial / Q000235:genetics; D000818:Animals; D002417:Cattle; D002645:Chickens; D002522:Chlorocebus aethiops; D019453:Escherichia coli O157 / Q000235:genetics / Q000302:isolation & purification*; D029968:Escherichia coli Proteins / Q000235:genetics; D005243:Feces / Q000382:microbiology; D005516:Food Microbiology; D006460:Hemolysin Proteins / Q000235:genetics; D007723:Korea; D008460:Meat / Q000382:microbiology*; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods*; D019105:Random Amplified Polymorphic DNA Technique / Q000379:methods*; D011933:Reagent Kits, Diagnostic; D022622:Shiga Toxin 1 / Q000235:genetics; D022641:Shiga Toxin 2 / Q000235:genetics; D013552:Swine; D014481:United States; D014709:Vero Cells
D018829:Adhesins, Bacterial; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli; D011933:Reagent Kits, Diagnostic; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2; C073819:eaeA protein, E coli