Willshaw G A, Scotland S M, Smith H R, Cheasty T, Thomas A, Rowe B
Laboratory of Enteric Pathogens, Central Public Health Laboratory, London, United Kingdom.
J Clin Microbiol. 1994 Apr;32(4):897-902. doi: 10.1128/jcm.32.4.897-902.1994.
A total of 375 Escherichia coli O157 strains were tested by colony hybridization with the eae probe from the central portion of the eaeA gene of the classical enteropathogenic E. coli strain E2348/69. They were also tested with a probe, eaeO157, from the C-terminal end of the eae gene homolog from a Vero cytotoxin (VT)-producing strain of E. coli (VTEC) of serotype O157:H7. Both probes hybridized with all 246 O157:H7 or H- VTEC strains tested. The majority were from human infections, and the remainder were from cattle. A further 10 strains (H7 or H-) hybridized with both eae and eaeO157 sequences but not with VT probes. They resembled O157 VTEC and were probably naturally occurring derivatives that had lost VT genes. The remaining 119 strains of O157 were from human, animal, and food sources and belonged to 16 H types other than H7 or were H-. They were VT negative and differed in their properties from O157 VTEC: generally they fermented sorbitol in 1 day, produced beta-glucuronidase, and could not be phage typed by the scheme for O157 VTEC. The eae probe but not the eaeO157 sequence hybridized with 18 H8 or H39 strains, predominantly from human diarrhea. The remaining 101 VT-negative strains hybridized with neither probe. However, 16 strains of O157:H45 hybridized with a probe for diffusely adherent E. coli and attached to HEp-2 cells in a diffuse pattern. Serogroup O157 comprises strains with heterogeneous properties. The eaeO157 probe is a valuable addition to the VT probes used to differentiate O157 strains.
采用来自典型肠致病性大肠杆菌菌株E2348/69的eaeA基因中部的eae探针，通过菌落杂交法对总共375株大肠杆菌O157菌株进行了检测。还用一种来自血清型为O157:H7的产志贺毒素大肠杆菌（VTEC）的eae基因同源物C末端的探针eaeO157对这些菌株进行了检测。两种探针均与所有检测的246株O157:H7或H-VTEC菌株杂交。其中大多数菌株来自人类感染，其余来自牛。另有10株菌株（H7或H-）与eae和eaeO157序列均杂交，但不与VT探针杂交。它们类似于O157 VTEC，可能是天然存在的已失去VT基因的衍生物。其余119株O157菌株来自人类、动物和食物来源，属于除H7以外的16种H型或为H-型。它们VT阴性，特性与O157 VTEC不同：一般来说，它们在1天内发酵山梨醇，产生β-葡萄糖醛酸酶，并且不能用O157 VTEC的分型方案进行噬菌体分型。eae探针而非eaeO157序列与18株H8或H39菌株杂交，这些菌株主要来自人类腹泻。其余101株VT阴性菌株均未与任何一种探针杂交。然而，16株O157:H45菌株与一种用于检测弥漫性粘附大肠杆菌的探针杂交，并以弥漫性模式附着于HEP-2细胞。O157血清群包含特性各异的菌株。eaeO157探针是用于区分O157菌株的VT探针的一个有价值的补充。
