Giles J S, Hariharan H, Heaney S B
Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Canada.
Can J Microbiol. 1995 Mar;41(3):209-16. doi: 10.1139/m95-029.
The plasmid profiles of oxytetracycline- and streptomycin-resistant isolates of Aeromonas salmonicida, Vibrio anguillarum, and Vibrio ordalii were examined by agarose gel electrophoresis. Bacterial isolates were from disease outbreaks in fish on the Atlantic and Pacific coasts. Resistant isolates were examined when grown in the presence and absence of antibiotic. Alkaline lysis methods were used for plasmid isolation. Vibrio spp. were predominantly plasmidless, except for a 47-kilobase (kb) plasmid. Atlantic coast isolates of A. salmonicida possessed four or six plasmids, with four smaller plasmids ranging in size from 4.3 to 8.1 kb being consistently observed. The plasmid profiles of antibiotic-sensitive ATCC strains were identical. The plasmid profiles of the Pacific coast isolates of A. salmonicida varied slightly from those of the Atlantic coast isolates with six plasmids observed, ranging in size from 4.2 to 8.9 kb. Resistance to the antibiotics was not altered following plasmid curing experiments and resistance was not transferable to Escherichia coli. Thus, resistance to oxytetracycline and streptomycin did not appear to be plasmid mediated.
通过琼脂糖凝胶电泳检测了杀鲑气单胞菌、鳗弧菌和奥氏弧菌对土霉素和链霉素耐药菌株的质粒图谱。细菌分离株来自大西洋和太平洋沿岸鱼类疾病暴发。在有抗生素和无抗生素存在的情况下培养时，对耐药分离株进行了检测。采用碱裂解法分离质粒。除了一个47千碱基（kb）的质粒外，弧菌属主要无质粒。大西洋沿岸的杀鲑气单胞菌分离株有四个或六个质粒，始终能观察到四个较小的质粒，大小在4.3至8.1 kb之间。抗生素敏感的ATCC菌株的质粒图谱相同。太平洋沿岸杀鲑气单胞菌分离株的质粒图谱与大西洋沿岸分离株略有不同，观察到六个质粒，大小在4.2至8.9 kb之间。质粒消除实验后，对这些抗生素的耐药性没有改变，且耐药性不能转移到大肠杆菌。因此，对土霉素和链霉素的耐药性似乎不是由质粒介导的。
