【摘要】 从周宁县某养殖场史氏鲟病灶样品中分离出1株多重耐药革兰氏阳性菌JY08,为了进一步研究其进化地位、耐药机制和潜在致病因子,采用形态学特征、16S rRNA基因序列、生理生化特征和系统发育树对其进行鉴定。结果显示,菌株JY08的形态特征和生理生化特性与腐生葡萄球菌(Staphylococcus saprophyticus)基本一致;16S rRNA基因序列与腐生葡萄球菌的相似度最高,为100%;系统发育树显示菌株JY08与腐生葡萄球菌腐生亚种(Staphylococcus saprophyticus subsp.saprophyticus ATCC 15305)聚为一支,结合全自动细菌鉴定仪生理生化特性鉴定结果和16S rRNA基因序列分析结果鉴定该菌株为腐生葡萄球菌。药敏试验结果表明,菌株JY08对β-内酰胺类、大环内酯类、磺胺类和林可霉素类等大类中的17种药物具有耐药性;对氨基糖苷类、喹诺酮类和氯霉素类等11种药物敏感;对多粘菌素B和呋喃唑酮2种药物中度敏感。耐药基因和毒力因子分析结果显示菌株JY08携带了10大类103个抗生素耐药基因和61种毒力因子123个相关毒力基因。本文研究结果为进一步评估该菌株潜在的具有感染能力的遗传特征提供科学数据,同时为该菌可能引起的疾病防控提供科学资料。更多还原

【Abstract】 A multi-drug resistant Gram-positive bacterium JY08 was isolated from Acipenser schrenckii lesion sample from a farm in Zhouning, and its evolutionary relationship, drug resistance mechanism and potential pathogenic factors were further studied.Morphological characteristics, 16 S rRNA gene sequencing, physiological and biochemical characteristics and analysis of phylogenetic tree were performed to identify strain JY08.The results showed that strain JY08 was basically consistent with the morphological and biochemical characteristics of Staphylococcus saprophyticus.The 16 S rRNA gene had a 100% similarity with S.saprophyticus.Strain JY08 was clustered into the one clade with S.saprophyticus by analysis of phylogenetic tree based on the 16 S rRNA gene sequence.Combing the physiological and biochemical characteristics, and 16 S rRNA gene sequncing, strain JY08 was identified as a member of S.saprophyticus.The results of drug susceptibility test showed that strain JY08 was resistant to 17 drugs belong to β-lactams, macrolides, sulfonamides and lincomycins, etc; sensitive to 11 drugs belong to aminoglycosides, quinolones and chloramphenicols, etc; moderately sensitive to polymyxin B and furazolidone.The analysis of drug resistance genes and virulence factors showed that strain JY08 carried 103 antibiotic resistance genes in 10 categories and 123 virulence related genes in 61 virulence factors.The results of this study provided scientific data for further evaluating the genetic characteristics of this strain of fish infections, and at the same time provided scientific data for the prevention and control of diseases caused by this strain.更多还原