Prevalence and Characterization of Staphylococcus aureus Isolated From Pasteurized Milk in China
Prevalence and Characterization of Staphylococcus aureus Isolated From Pasteurized Milk in China
复制标题
中国巴氏杀菌牛奶中金黄色葡萄球菌的流行情况及特征
DOI：
10.3389/fmicb.2019.00641
复制
发表时间：
2019-04-02
影响因子：
5.2
通讯作者：
Haoming Wu
中科院分区：
文献类型：
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作者：
Dai, Jingsha;Wu, Shi;Haoming Wu
金黄色葡萄球菌是全球最重要的食源性病原体之一。它产生各种毒素和侵入性酶，可以在许多食品中找到。牛奶是葡萄球菌食物中毒的重要来源。巴氏杀菌后，这种微生物或其肠毒素可能仍保留在巴氏杀菌牛奶中。因此，这项研究是为了研究来自中国39个城市的258个巴氏杀菌牛奶中金黄色葡萄球菌的污染。这些样品中金黄色葡萄球菌的患病率和水平以及抗生素易感性谱，毒力基因，生物膜形成和与生物膜相关的基因，SPA键入和MLST用于确定分离物之间的表征。发现在中国39个城市中有8个发现了3.9％的样品。受污染的水平不是很过大，显示出最正面样品的MPN值（9/10）小于1 mpn/g。所有与奶油相关的金黄色葡萄球菌分离株都具有生物膜和ICAA，ICAD，ICAD，ENO，CLFA，CLFB，CLFB，FNBA，FNBA，FNBB，FNBB，FIB基因，其他与生物膜相关的基因，以及91.7％的分离株和CNA基因在50％中显示出91.7％的分离株和CNA基因，除非Bap Gene，否则BAP基因除外。抗生素易感性测试表明，所有分离株均具有抗不同浓度的抗生素的耐药性或中等耐药性。此外，75.0％的分离株对三个或多个抗生素类别具有抗性，这表明多药耐药性。分离株具有毒力潜能，显示了一个或多个与毒力相关的基因的分离株的66.7％（8/12）。通过MLST和SPA键入的分子键入将这些分离株分类为总共11种序列类型（STS）和SPA类型，这表明遗传多样性很高。这些类型大多数与各种临床金黄色葡萄球菌感染有关。因此，这项研究的结果反映了中国金黄色葡萄球菌感染的潜在风险。我们的研究还提供了对巴氏杀菌牛奶中金黄色葡萄球菌患病率的全面分析，并有助于确保通过有效的抗生素对人类感染进行更准确的治疗。
Staphylococcus aureus is one of the most important food-borne pathogens globally. It produces various toxins and invasive enzymes and can be found in numerous food products. Milk is an important source of staphylococcal food poisoning. After pasteurization, this microorganism or its enterotoxins might still remain in pasteurized milk. Therefore, this study was to investigate the contamination of S. aureus in 258 pasteurized milk from 39 cities of China. The prevalence and levels of S. aureus in these samples as well as antibiotic susceptibility profiles, virulence genes, biofilm formation, and biofilm related genes, spa typing and MLST were used to determine the characterization among the isolates. It was found 3.9% of samples were detected S. aureus in 8 of 39 cities in China. The contaminated level were not very excessive which showed the MPN values of the most positive samples (9/10) were less than 1 MPN/g. All pasteurized milk-related S. aureus isolates have ability to produce biofilm and harbored icaA, icaD, eno, clfA, clfB, fnbA, fnbB, fib genes, other biofilm related genes icaC were showed in 91.7% of isolates and cna gene were showed in 50%, except bap gene which were free in all isolates. The antibiotic susceptibility test showed that all isolates were resistant or intermediate-resistant to different concentrations of the antibiotics. Furthermore, 75.0% of the isolates were resistant to three or more antibiotic classes, which indicated multidrug resistance. The isolates had virulence potential, which showed 66.7% (8/12) of the isolates carried one or more virulence-associated genes. Molecular typing by MLST and spa typing enabled classification of these isolates into a total of 11 sequence types (STs) and spa types, which indicated high genetic diversity. Most of these types were related to various clinical S. aureus infections. Thus, the findings of this study reflect the potential risk of S. aureus infection in China. Our study also provides comprehensive analysis of the prevalence of S. aureus in pasteurized milk and helps ensure more accurate treatment of human infection with effective antibiotics.