Department of Microbiology, University of Maryland at College Park, 20742, College Park, MD, USA.
World J Microbiol Biotechnol. 1995 Sep;11(5):572-7. doi: 10.1007/BF00286376.
Vibrio cholerae O1 and V. cholerae non-O1 strains isolated from environmental samples collected in São Paulo, Brazil, during cholera epidemics and pre-epidemic periods were examined for the presence of toxin genes. V. cholerae O1 strains isolated from clinical samples in Peru and Mexico, and V. cholerae O139 strains from India were also examined for the presence of ctx (cholera toxin gene) and zot (zonula occludens toxin gene) by polymerase chain reaction (PCR). A modified DNA-extraction method applied in this study yielded satisfactory recovery of genomic DNA from vibrios. Results showed that strains of V. cholerae O1 isolated during the preepidemic period were ctx (-)/zot (-) whereas strains isolated during the epidemic were ctx (+)/zot (+). All V. cholerae non-O1 strains tested in the study were ctx (-)/zot (-), whereas all V. cholerae O139 strains were ctx (+)/zot (+). Rapid detection of the virulence genes (ctx and zot) can be achieved by PCR and this can serve as an important tool in the epidemiology and surveillance of V. cholerae.
从巴西圣保罗在霍乱流行和流行前期间采集的环境样本中分离出的霍乱弧菌 O1 和非 O1 菌株，检查其是否存在毒素基因。还通过聚合酶链反应 (PCR) 检查了从秘鲁和墨西哥临床样本中分离出的霍乱弧菌 O1 菌株以及从印度分离出的霍乱弧菌 O139 菌株是否存在 ctx（霍乱毒素基因）和 zot（紧密连接毒素基因）。本研究中应用的改良 DNA 提取方法从弧菌中获得了令人满意的基因组 DNA 回收。结果表明，流行前期间分离的霍乱弧菌 O1 菌株为 ctx (-)/zot (-)，而流行期间分离的菌株为 ctx (+)/zot (+)。研究中测试的所有非 O1 霍乱弧菌菌株均为 ctx (-)/zot (-)，而所有霍乱弧菌 O139 菌株均为 ctx (+)/zot (+)。PCR 可快速检测毒力基因（ctx 和 zot），这可作为霍乱弧菌流行病学和监测的重要工具。
