Abstract：
Understanding Shiga toxin subtypes in E. coli from reservoir hosts may give insight into their significance as human pathogens. The data also serve as an epidemiological tool for source tracking. We characterized Shiga toxin subtypes in 491 goat E. coli isolates (STEC) from the mid-Atlantic US region (stx1 = 278, stx2 = 213, and stx1/stx2 = 95). Their serogroups, phylogroups, M13RAPD genotypes, eae (intimin), and hly (hemolysin) genes were also evaluated. STEC-positive for stx1 harbored Stx1c (79%), stx1a (21%), and stx a/c (4%). Those positive for Stx2 harbored stx2a (55%) and Stx2b (32%), while stx2a/stx2d and stx2a/stx2b were each 2%. Among the 343 STEC that were serogrouped, 46% (n = 158) belonged to O8, 20% (n = 67) to 076, 12% (n = 42) to O91, 5% (n = 17) to O5, and 5% (n = 18) to O26. Less than 5% belonged to O78, O87, O146, and O103. The hly and eae genes were detected in 48% and 14% of STEC, respectively. Most belonged to phylogroup B1 (73%), followed by D (10%), E (8%), A (4%), B2 (4%), and F (1%). M13RAPD genotyping revealed clonality of 091, O5, O87, O103, and O78 but higher diversity in the O8, O76, and O26 serogroups. These results indicate goat STEC belonged to important non-O157 STEC serogroups, were genomically diverse, and harbored Shiga toxin subtypes associated with severe human disease.
摘要：
了解来自水库宿主的大肠杆菌中的志贺毒素亚型可以深入了解它们作为人类病原体的重要性。这些数据还可以作为源跟踪的流行病学工具。我们对来自美国大西洋中部地区的491种山羊大肠杆菌分离株（STEC）中的志贺毒素亚型进行了表征（stx1=278，stx2=213和stx1/stx2=95）。他们的血清群，系统组，M13RAPD基因型，eae（内膜），和hly（溶血素）基因也被评估。STEC-harboredStx1c的stx1阳性（79%），stx1a（21%），和stxa/c（4%）。Stx2harboredstx2a(55%)和Stx2b(32%)阳性，而stx2a/stx2d和stx2a/stx2b各为2%。在343个STEC中，46%(n=158)属于O8,20%(n=67)属于076,12%(n=42)属于O91,5%(n=17)属于O5,5%(n=18)属于O26。小于5%属于O78、O87、O146和O103。在48％和14％的STEC中检测到hly和eae基因，分别。大多数属于系统群B1(73%)，其次是D（10%），E（8%），A（4%），B2（4%），F（1%）。M13RAPD基因分型揭示了091，O5，O87，O103和O78的克隆性，但在O8，O76和O26血清群中的多样性更高。这些结果表明山羊STEC属于重要的非O157STEC血清群，基因组多样，并携带与严重人类疾病相关的志贺毒素亚型。
