论文部分内容阅读
The Chinese giant salamander(Andrias davidianus) is the largest living amphibian in the world. Aeromonas hydrophila strain L602 was isolated from A. davidianus. The 16S rDNA gene of this isolate was amplified using PCR,and the phylogenetic tree was constructed by the neighbor-joining method. Four virulence genes(aerA,aha1,hly and alt) of A. hydrophila were amplified by PCR and drug resistances were tested using Kirby-Bauer disk diffusion method. The results showed that the length of this 16S rDNA sequence was 1453 bp,which showed 99% homology with A. hydrophila. The GenBank accession number was JX155398. Phylogenetic analysis indicated it grouped together with A. hydrophila. Four virulence genes were all detected,indicating that strain L602 was highly virulent. This stain was resistant to four antibiotics(vibramycin,furazolidone,ampicillin and erythromycin),while it was insensitive to streptomycin. Furthermore,this strain was susceptible to six antibiotics(sulfafurazole,ciprofloxacin,penbritin,norfloxacin,florfenicol and enrofloxacin). This study will help to validate the classification and virulence of pathogenic bacteria in amphibians.
The Chinese giant salamander (Andrias davidianus) is the largest living amphibian in the world. Aeromonas hydrophila strain L602 was isolated from A. davidianus. The 16S rDNA gene of this isolate was amplified using PCR, and the phylogenetic tree was constructed by the neighbor- The method showed four the virulence genes (aerA, aha1, hly and alt) of A. hydrophila were amplified by PCR and drug resistance were tested using a Kirby-Bauer disk diffusion method. The results showed that the length of this 16S rDNA sequence was 1453 bp , which showed 99% homology with A. hydrophila. The GenBank accession number was JX155398. Phylogenetic analysis indicated it grouped together with A. hydrophila. Four virulence genes were all detected, indicating that strain L602 was highly virulent. This stain was resistant to four antibiotics (vibramycin, furazolidone, ampicillin and erythromycin), while it was insensitive to streptomycin. Furthermore, this strain was susceptible to six antibiotics (sulfafurazole, ciprofloxacin, p enbritin, norfloxacin, florfenicol and enrofloxacin). This study will help to validate the classification and virulence of pathogenic bacteria in amphibians.