| 牛源金黄色葡萄球菌生物被膜与毒素基因检测及agr分型 |
| |
| 引用本文： | 张行,李新圃,武小虎,丁学智,严作廷,王胜义,李宏胜.牛源金黄色葡萄球菌生物被膜与毒素基因检测及agr分型[J].畜牧兽医学报,2020,51(11):2903-2910. |
| |
| 作者姓名： | 张行 李新圃 武小虎 丁学智 严作廷 王胜义 李宏胜 |
| |
| 作者单位： | 中国农业科学院兰州畜牧与兽药研究所/农业农村部兽用药物创制重点实验室, 甘肃省中兽药工程技术研究中心, 兰州 730050 |
| |
| 基金项目： | 国家重点研发项目（2017YFD0502200）；甘肃省国际科技合作项目（17YF1 WA169）；中国农业科学院奶牛疾病研究创新工程项目（CAAS-ASTIP-2014-LIHPS-03） |
| |
| 摘 要： | 旨在对牛源金黄色葡萄球菌（Staphylococcus aureus，S.aureus）的生物被膜、耐药性、毒素基因和agr基因型进行研究，并分析agr基因型与毒素基因之间的相关性。分别用微量滴定板法、药敏纸片法和PCR对S.aureus的生物被膜、耐药性和毒素基因进行检测，用多重PCR对S.aureus进行agr分型。结果表明，336株牛源S.aureus均能形成生物被膜，其中，形成中等（++）和强（+++）生物被膜的S.aureus分别占52.1%和47.9%。药敏试验结果显示，S.aureus对青霉素耐药最为严重，耐药率达91.7%，其次是红霉素、卡那霉素、克林霉素和庆大霉素，耐药率分别为89.6%、72.9%、66.7%和60.4%，而所有S.aureus对呋喃妥因和利奈唑胺均表现为敏感。PCR检测结果显示，黏附素基因fnbA检出率最高，达99.7%，其次是icaD、icaA、clfA和cna，检出率分别为98.2%、89.6%、86.0%和56.0%，bap基因检出率最低，为14.6%。肠毒素基因sea的检出率为26.5%，其次是seb（8.3%）和sec（6.8%），毒素基因tst的检出率占8.3%。分型结果显示，agr Ⅰ型S.aureus是主要的流行菌株，占77.1%，agr Ⅱ、agr Ⅲ和agr Ⅳ型S.aureus流行率分别为14.0%、4.8%和2.1%。统计分析结果表明，agr Ⅰ型S.aureus更具有携带多种毒素基因的潜力，而agr Ⅳ型S.aureus无毒素基因携带潜力。综上表明，牛乳腺炎性S.aureus对常见的抗菌药物耐药严重，毒素基因分布多样，agr Ⅰ型是奶牛乳腺炎性S.aureus主要的基因型，且具有携带多种毒素基因的能力，其潜在威胁应引起重视。
|
| 关 键 词： | 奶牛乳腺炎 金黄色葡萄球菌 生物被膜 毒素基因 agr分型 |
| 收稿时间： | 2020-04-20 |
Investigation of Biofilm Formation,Virulence Genes and agr Typing of Staphylococcus aureus from Bovine Mastitis Cases |
| |
| ZHANG Hang,LI Xinpu,WU Xiaohu,DING Xuezhi,YAN Zuoting,WANG Shengyi,LI Hongsheng.Investigation of Biofilm Formation,Virulence Genes and agr Typing of Staphylococcus aureus from Bovine Mastitis Cases[J].Acta Veterinaria et Zootechnica Sinica,2020,51(11):2903-2910. |
| |
| Authors: | ZHANG Hang LI Xinpu WU Xiaohu DING Xuezhi YAN Zuoting WANG Shengyi LI Hongsheng |
| |
| Institution: | Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences/Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Engineering and Technology Research Center of Traditional Chinese Veterinary Medicine, Lanzhou 730050, China |
| |
| Abstract: | The objective of the present study was to investigate the biofilm formation, antimicrobial resistance, virulence genes, and agr genotypes of Staphylococcus aureus (S. aureus) isolated from bovine mastitis cases, and to analyze the correlations between agr genotypes and virulence genes. Biofilm formation, antimicrobial resistance, and virulence genes for 336 strains of S. aureus were detected by microtiter plate method, disk diffusion method, and PCR respectively, and the agr typing of tested strains was determined by multiplex PCR. The results showed that all 336 strains of S. aureus from bovine mastitis were biofilm producers, among which 52.1% and 47.9% of isolates tested were moderate (++) and strong (+++) biofilm producers, respectively. Antimicrobial susceptibility testing demonstrated that S. aureus strains were highly resistant to penicillin, with a resistance rate of 91.7%, followed by erythromycin (89.6%), kanamycin (72.9%), clindamycin (66.7%) and gentamicin (60.4%). However, all isolates were sensitive to nitrofurantoin and linezolid. PCR results showed that the prevalence of fnbA gene was the highest (99.7%), followed by icaD (98.2%), icaA (89.6%), clfA (86.0%), cna (56.0%), and bap (14.6%) genes. Moreover, the sea, seb, sec and tst genes were found in 26.5%, 8.3%, 6.8% and 8.3% of the isolates, respectively. The agr typing results showed that S. aureus strains belonging to agr Ⅰ was predominant in our study, accounting for 77.1% of the isolates, and the frequencies of agr Ⅱ, agr Ⅲ and agr Ⅳ genotypes were 14.0%, 4.8% and 2.1%, respectively. Statistical analysis indicated that the strains of S. aureus belonging to agr Ⅰ genotype have the potential to carry more virulence genes, while no toxin genes could be found in any of the strains belonging to agr Ⅳ. The results revealed high antimicrobial resistance to common antimicrobial agents in S. aureus isolated from bovine mastitis milk samples. Moreover, agr Ⅰ was the predominant genotype with diverse toxin genes in S. aureus from bovine mastitis, and the potential hazard should be of concern. |
| |
| Keywords: | bovine mastitis Staphylococcus aureus biofilm virulence genes agr typing |
|
| 点击此处可从《畜牧兽医学报》浏览原始摘要信息 |
| 点击此处可从《畜牧兽医学报》下载免费的PDF全文 |
|
