Blanco M, Blanco J E, Blanco J
Departamento de Microbioloxía e Parasitoloxía, Facultade de Veterinaria, Universidade de Santiago, Lugo.
Microbiologia. 1993 Apr;9(1):72-6.
A total of 54 K99+ and/or F41+ Escherichia coli strains isolated of calves and piglets with diarrhoea in different countries were investigated for production of heat-labile (LT) and heat-stable (STa) enterotoxins, verotoxins (VT1 and VT2), cytotoxic necrotizing factors (CNF1 and CNF2), alpha-haemolysin (Hly) and enterohaemolysin (EntHly). Fifty-one (94%) strains were STa+, two (4%) were STa+CNF1+Hly+ and one (2%) was not toxigenic. The two STa+CNF1+Hly+ E. coli strains expressed the K99 intestinal colonization factor and belonged to serotype O8:K25. The majority of STa-producing E. coli were K99+ and F41+ and belonged to serotypes O9:K(A)35, O101:K(A)28 and O101:K(A)30. All enterotoxigenic strains assayed in this study were negative for expression of the Att25, Vir and B23 adhesins recently detected in E. coli that cause infections in calves.
对从不同国家患腹泻的犊牛和仔猪中分离出的54株K99+和/或F41+大肠杆菌菌株进行了研究，检测其热不稳定肠毒素（LT）、热稳定肠毒素（STa）、志贺毒素（VT1和VT2）、细胞毒性坏死因子（CNF1和CNF2）、α溶血素（Hly）和肠溶血素（EntHly）的产生情况。51株（94%）菌株为STa+，2株（4%）为STa+CNF1+Hly+，1株（2%）不产毒素。这两株STa+CNF1+Hly+大肠杆菌菌株表达K99肠道定植因子，属于O8:K25血清型。大多数产STa的大肠杆菌为K99+和F41+，属于O9:K(A)35、O101:K(A)28和O101:K(A)30血清型。本研究中检测的所有产肠毒素菌株对最近在引起犊牛感染的大肠杆菌中检测到的Att25、Vir和B23黏附素的表达均为阴性。
