Characteristics of verotoxin non-producing Escherichia coli O157 and verotoxin-producing E coli isolated from healthy cattle

Jung, Byeong-yeal; Jung, Suk-chan; Park, Hong-je; Cho, Gil-jae; Kim, Bong-hwan

Korean Journal of Veterinary Research 2000;40(3):525-531.

Byeong-yeal Jung¹, Suk-chan Jung¹, Hong-je Park², Gil-jae Cho³, Bong-hwan Kim⁴

¹Bacteriology Division, National Veterinary Research and Quarantine Service
²Microbiological Research Institute, KOMED
³Equine Hospital, Korea Racing Association
⁴College of Veterinary Medicine, Kyungpook National University

정상 소 분변에서 분리한 verotoxin을 산생하지 않는 Escherichia coli O157과 verotoxin을 산생하는 E coli의 특성 조사

정병열¹, 정석찬¹, 박홍제², 조길재³, 김봉환⁴

¹국립수의과학검역원 세균과
²(주)코메드 미생물연구소
³한국마사회 마필보건소
⁴경북대학교 수의과대학

Abstract

Verotoxin non-producing E coli O157 strains have been isolated from cattle feces and compared in particular regard to biochemical properties and genotypes with verotoxin-producing E coli (VTEC). E coli O157 : nonH7 strains had different phenotypes in sorbitol fermentation and ${eta}-glucuronidase$ activity from E coli O157 : H7. Regardless of verotoxin production ability of E coli O157 : H7, uidA gene was uniquely detected from sorbitol and ${eta}-glucuronidase$ negative E coli O157 : H7. Forty five fecal samples from 6 dairy farms were obtained and VTEC was detected as 15.6% (7 strains) of the samples. Most VTEC isolates were positive for sorbitol fermentation and ${eta}-glucuronidase$ activity but negative for eaeA gene. This study suggested that cattle could be a reservior for VTEC. However, absence of eaeA gene in VTEC isolates from most of healthy cattle suggested that they might be less virulent than eaeA-positive E coli against human health.

Key Words: E coli O157 : H7, E coli O157 : nonH7, Verotoxin, uidA, eaeA