Isiko J, Khaitsa M, Bergholz T M
Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND, USA.
College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda.
Lett Appl Microbiol. 2015 Jun;60(6):552-7. doi: 10.1111/lam.12404. Epub 2015 Mar 16.
The objective of this study was to assess the genetic diversity of non-O157 Shiga toxin-producing Escherichia coli (STEC) isolates from cattle. Multi-locus sequence typing (MLST) was used to identify and compare the sequence types (STs) of 43 non-O157 STEC cattle isolates using the EcMLST database curated by the STEC Center at Michigan State University. For the 43 isolates, 19 STs were identified and 10 of those STs were novel compared to those in EcMLST. For the 43 isolates, 19 different serotypes were identified. STEC O22:H8, O174:H28 and O8:H19 were most common, and STEC O8 isolates were the most diverse, with seven different STs for isolates with that O group. STEC strains with O types identified in this study have been isolated from cattle by other researchers, as well as from cases of human gastroenteritis. Of the 10 novel STs identified, six were found to be closely related to previously identified STs, indicating that populations of non-O157 STEC in cattle are similar to those from other sources, including human clinical cases. Significance and impact of the study: The foodborne pathogen Shiga toxin-producing Escherichia coli (STEC) is a significant public health concern. One of the main reservoirs for STEC are cattle, which can directly or indirectly contribute to STEC in the food supply. The genetic subtype data presented here highlight the diversity of STEC that can be isolated from cattle. These results further our understanding of the ecology of STEC in the primary production environment, which is important for developing effective control measures to reduce this pathogen in the food supply.
本研究的目的是评估来自牛的非O157产志贺毒素大肠杆菌（STEC）分离株的遗传多样性。使用多位点序列分型（MLST），通过密歇根州立大学STEC中心管理的EcMLST数据库，对43株非O157 STEC牛分离株的序列类型（STs）进行鉴定和比较。对于这43株分离株，鉴定出19种STs，其中10种STs与EcMLST中的相比是新的。对于这43株分离株，鉴定出19种不同的血清型。STEC O22:H8、O174:H28和O8:H19最为常见，O8血清型的STEC分离株最为多样，该血清型的分离株有7种不同的STs。本研究中鉴定出的O型STEC菌株已被其他研究人员从牛以及人类胃肠炎病例中分离出来。在鉴定出的10种新STs中，有6种被发现与先前鉴定的STs密切相关，这表明牛中非O157 STEC的种群与包括人类临床病例在内的其他来源的种群相似。研究的意义和影响：食源性病原体产志贺毒素大肠杆菌（STEC）是一个重大的公共卫生问题。STEC的主要宿主之一是牛，牛可直接或间接导致食品供应中出现STEC。此处呈现的遗传亚型数据突出了可从牛中分离出的STEC的多样性。这些结果进一步加深了我们对STEC在初级生产环境中的生态学的理解，这对于制定有效的控制措施以减少食品供应中的这种病原体很重要。
