Molecular analysis of non-O1, non-O139 Vibrio cholerae associated with an unusual upsurge in the incidence of cholera-like disease in Calcutta, India
Molecular analysis of non-O1, non-O139 Vibrio cholerae associated with an unusual upsurge in the incidence of cholera-like disease in Calcutta, India
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DOI：
10.1128/jcm.36.3.756-763.1998
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发表时间：
1998-03-01
影响因子：
9.4
通讯作者：
Nair, GB
中科院分区：
文献类型：
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作者：
Sharma, C;Thungapathra, M;Nair, GB
1996年2月至3月，在印度加尔各答传染病医院住院的患者中，非Ol、非O139霍乱弧菌的发病率莫名其妙地激增。在此期间分离的18株霍乱弧菌中，15株属于非O1、非O139血清群(4株属于O144，3株属于O11，1株属于O6、O8、O12、O19、O39和O58，2株无法分型)，2株属于O139血清群，1株属于O1血清群。13株具有代表性的非O1、非O139霍乱弧菌的无细胞培养上清液对CHO和HeLa细胞有明显的细胞毒作用，并产生非膜损伤的细胞毒素。经多项聚合酶链式反应检测，非O1、非O139菌株的ctxA、tot、ace和tcpA基因以及代表大肠杆菌不耐热毒素、耐热毒素和vero毒素的基因及这些基因的各种变异体均为阳性。用rRNA基因和其他基因(hlyA、hlyU、hlx、toxR和attRS1)的限制性片段长度多态性(RFLP)分析和脉冲场凝胶电泳法(PFGE)对非Ol、非O139V：霍乱弧菌的克隆性进行了研究，结果表明，1996年2月和3月的霍乱流行是由不同克隆的菌株引起的。总体而言，核糖体分型、不同基因的RFLP分析和PFGE结果之间有很好的相关性，属于特定血清组的菌株显示出几乎相同的限制性内切酶图谱和PFGE图谱。本研究表明，霍乱弧菌的某些血清群可引起腹泻，其机制与产毒霍乱弧菌O1和O139完全不同，我们建议将这些血清群包括在肠源性霍乱弧菌的命名中。
There was an inexplicable upsurge in the incidence of non-Ol, non-O139 Vibrio cholerae among hospitalized patients admitted to the Infectious Diseases Hospital, Calcutta, India, between February and March 1996. Of the 18 strains of V. cholerae isolated during this period, 15 belonged to the non-Ol, non-O139 serogroups (4 belonged to O144, 3 belonged to O11, 1 each belonged to O6, O8, O12, O19, O39, and O58, and 2 strains could not be typed), 2 belonged to the O139 serogroup, and 1 belonged to the O1 serogroup. Cell-free culture supernatants of 13 representative non-Ol, non-O139 V. cholerae strains evoked a distinct cytotoxic effect on CHO and HeLa cells, and the strains examined produced the nonmembrane-damaging cytotoxin. By several PCR assays, it was determined that none of the non-Ol, non-O139 strains were positive for the ctxA, tot, ace, and tcpA genes and for the genes representing the heat-labile toxin, heat-stable toxin, and verotoxin of Escherichia coli and the various variants of these genes. Studies on the clonality of non-Ol, non-O139 V: cholerae strains by restriction fragment length polymorphism (RFLP) analysis of rRNA genes and of other genes (hlyA, hlyU, hlx, toxR, and attRS1) and by pulsed-field gel electrophoresis (PFGE) collectively indicate that the upsurge which occurred in February and March 1996 was caused by strains belonging to different clones. Overall, there was an excellent correlation between the results of ribotyping, RFLP analysis of various genes, and PFGE, with strains belonging to a particular serogroup showing nearly identical restriction patterns and PFGE profiles. It is clear from this study that some serogroups of V. cholerae can cause diarrhea by a mechanism quite different from that of toxigenic V. cholerae O1 and O139, and we have proposed the nomenclature of enteropathogenic V. cholerae to include these serogroups.