文献类型： 外文期刊

作者： Zhang, Pengfei ¹ ; Liu, Xinyu ¹ ; Zhang, Jie ¹ ; Fu, Xueting ¹ ; Wan, Yangli ¹ ; Pan, Hu ² ; Wu, Congming ³ ; Wang, Xin ¹ ;

作者机构： 1.Northwest A&F Univ, Coll Food Sci & Engn, Yangling 712100, Shaanxi, Peoples R China

2.Tibet Acad Agr & Anim Husb Sci, Inst Agr Prod Qual Stand & Testing Res, Lhasa Tibet 850032, Peoples R China

3.China Agr Univ, Coll Vet Med, Beijing 100193, Peoples R China

关键词： Staph; aureus; MRSA; yak butter; molecular characteristics; antibiotic resistance

期刊名称：JOURNAL OF DAIRY SCIENCE （ 影响因子：4.034； 五年影响因子：4.354 ）

ISSN： 0022-0302

年卷期： 2021 年 104 卷 9 期

页码：

收录情况： SCI

摘要： This study aimed to investigate the prevalence, molecular characteristics and antibiotic resistance of Staphylococcus aureus isolates from yak butter in Ti-bet, China. A total of 218 yak butter samples were collected from retail stores in Tibet and screened for Staph. aureus. Furthermore, the virulence genes, resis-tance genes, antimicrobial susceptibility, and molecular typing [pulsed-field gel electrophoresis (PFGE), mul-tilo cus sequence typing, and staphylococcal protein A (spa) typing] of Staph. aureus isolates were detected. The results showed that 12.4% of yak butter samples were contaminated with Staph. aureus, including 5 samples positive for methicillin-resistant Staph. au-reus (MRSA). Among all isolates, 96.3% harbored one or more virulence genes, including classical (sea and sec), novel enterotoxin-enco ding genes (seh, sek, sel, and seq), and hemolysin genes (hla and hld). All isolates were resistant to at least 2 different antibiotic classes, and the isolates were most commonly resistant to sulfonamides, beta-lactams, and erythromycin. For resistance genes, blaZ (74.1%) was most frequently detected, followed by dfrG (51.9%), erm(B) (22.2%), mecA (18.5%), tet(K) (14.8%), aph(2 '')-Ia, aph(3 ')-III, and ant(6)-Ia (11.1% for each), and erm(C) (7.4%). We detected 8 spa types, 6 sequence types (ST), and 5 clonal complex (CC) types. In addition, 1 isolate of Staph. aureus was nontypeable. We found that CC1-ST1-t559 (55.6%) was the most predominant clone, followed by CC59-ST59-t437 (11.1%), CC5-ST5-t002 (7.4%), CC1-ST1, CC1-ST1-t114, CC1-ST573-t4938, CC1-ST573-t8915, CC30-ST30-t021, and CC25-ST25- t167 (3.7% for each). For PFGE typing, a total of 5 clusters and 15 pulsotypes were generated, and some isolates from different samples showed indistinguish-able pulsotypes. Our findings suggest that yak butter produced in Tibet, China, could be contaminated by Staph. aureus strains, including MRSA strains, carry-ing various virulence and resistance genes, represent-ing multiple antimicrobial resistance phenotypes. The presence of potentially virulent and antibiotic-resistant Staph. aureus strains in yak butter poses a potential threat to consumers, and appropriate measures need to be taken in the production chain to reduce the occur-rence of Staph. aureus in yak butter.