论文部分内容阅读
为鉴定长春市某水产养殖场团头鲂的病原菌,从患病团头鲂体内分离到致病菌JWC086,对其形态和生理生化特性进行了鉴定,并对16S r DNA和管家基因gyr B序列、毒力基因携带情况及耐药性进行了分析。结果显示,该菌为革兰阴性菌,其生理生化特性与维氏气单胞菌基本相同。16S r DNA序列比对结果表明,该菌与维氏气单胞菌(KP716691)的同源性在99%以上。基于16S r DNA与gyr B序列的进化分析显示,该菌与维氏气单胞菌同属一个分支,同源性较高。将分离菌人工感染团头鲂,7 d内团头鲂全部死亡,且临床症状与自然病例相似。通过毒力基因检测发现,能从JWC086扩增出气溶素(aer)、细胞毒性肠毒素(act)、黏附素(Aha)、丝氨酸蛋白酶(ser)、核酸酶(exu)、脂肪酶(lip)及密度感应系统调控基因(Lux S)等7种毒力因子。药敏试验结果显示,该菌对氟苯尼考及复方新诺明等药物比较敏感。本研究为团头鲂感染维氏气单胞菌的鉴定及治疗提供了科学依据。
In order to identify the pathogen of bream in Changchun aquaculture farm, the pathogen JWC086 was isolated from the diseased dactylidae, and its morphological and physiological and biochemical characteristics were identified. The 16S rDNA and gyr B sequence of housekeeping gene , The virulence of gene carriers and drug resistance were analyzed. The results showed that the bacteria is Gram-negative bacteria, its physiological and biochemical characteristics and Aeromonas vaginalis basically the same. The results of 16S r DNA sequence alignment showed that the homology of this strain with Aeromonas sobria (KP716691) was over 99%. Phylogenetic analysis based on 16S r DNA and gyr B sequences showed that the strain belonged to the same branch of Aeromonas sobria and had high homology. The isolated bacteria were infected with bovine sotalol, all died within 7 days, and the clinical symptoms were similar to those in natural cases. The results of virulence gene test showed that aerosols, cytotoxic enterotins, AHA, ser, nuc, lip, lipase and lipase were amplified from JWC086, And density sensor system regulation gene (Lux S) and other seven kinds of virulence factors. Drug sensitivity test results show that the bacteria on florfenicol and cotrimoxazole and other drugs more sensitive. This study provides a scientific basis for the identification and treatment of Aeromonas sobria infection.