Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin of Xinjiang Production & Construction Corps, College of Life Sciences, Tarim University, Alar, 86-843300, China.
College of Animal Sciences, Key Laboratory of Tarim Animal Husbandry and Science Technology of Xinjiang Production & Construction Corps, Tarim University, Alar, 86-843300, China.
Folia Microbiol (Praha). 2022 Apr;67(2):245-252. doi: 10.1007/s12223-021-00924-7. Epub 2021 Nov 4.
Staphylococcus aureus is an important pathogen of humans and animals. The aim of this study was to characterize 71 of S. aureus isolates from raw cow milk in southern Xinjiang of China, including molecular typing, distribution of virulence genes, and antimicrobial susceptibility. The isolates belonged to 18 sequence types (STs) (including 11 novel STs) and 6 spa types which were divided into five different clonal complexes (CCs), including CC188, CC352, CC22, CC398, and CC5406. The majority of the strains was grouped into multilocus sequence typing (MLST) CC188 (n = 41), t189 (n = 40), and ST5796 (n = 17). Only 30.9, 12.7, 11.3, and 9.9% of the isolates were resistant to erythromycin, clindamycin/norfloxacin, tetracycline, and gentamicin, respectively. Nine of multidrug resistant (MDR) isolates were observed which was associated with CC398-t2876. The adhesion molecules clfa, clfb, and hlb were most frequently detected with the percentage rate of 98.6% (70/71), 98.6% (70/71), and 90.1% (64/71), respectively. The percentage rates of the staphylococcal enterotoxin genes sea, seb, sec, sed, seg, and sei in S. aureus isolates were 5.6, 19.8, 40.8, 1.4, 49.3, and 30.9%, respectively. The see, seh, and sej genes were not found. This study provides data about the occurrence of S. aureus in raw cow milk, revealing high carriage frequency, drug resistance, and population structure of S. aureus. Furthermore, this study suggests that effective hygienic measures be taken when handling dairy cows, in order to prevent spreading MDR strains to human through direct contact and/or consumption of contaminated food.
金黄色葡萄球菌是人和动物的重要病原体。本研究旨在对中国新疆南部地区生牛乳中 71 株金黄色葡萄球菌进行特征分析，包括分子分型、毒力基因分布和抗菌药物敏感性。这些分离株属于 18 种序列型（ST）（包括 11 种新型 ST）和 6 种 spa 型，分为 5 种不同的克隆群（CC），包括 CC188、CC352、CC22、CC398 和 CC5406。大多数菌株被分为多位点序列分型（MLST）CC188（n=41）、t189（n=40）和 ST5796（n=17）。仅有 30.9%、12.7%、11.3%和 9.9%的分离株分别对红霉素、克林霉素/诺氟沙星、四环素和庆大霉素耐药。观察到 9 株耐多药（MDR）分离株与 CC398-t2876 相关。黏附分子 clfa、clfb 和 hlb 的检出率最高，分别为 98.6%（70/71）、98.6%（70/71）和 90.1%（64/71）。金黄色葡萄球菌分离株的肠毒素基因 sea、seb、sec、sed、seg 和 sei 的检出率分别为 5.6%、19.8%、40.8%、1.4%、49.3%和 30.9%。未发现 see、seh 和 sej 基因。本研究提供了生牛乳中金黄色葡萄球菌的发生情况数据，揭示了金黄色葡萄球菌的高携带频率、耐药性和种群结构。此外，本研究表明，在处理奶牛时应采取有效的卫生措施，以防止通过直接接触和/或食用受污染的食物将 MDR 菌株传播给人类。
