As. Pac. J. Mol. Biol. & Biotech., Dec 2002 Vol. 10 (2) : 103-108

Molecular Subtyping of Clinical Isolates Vibrio cholerae from Malaysia and Vietnam by Pulsed-field Gel Electrophoresis.

Thong Kwai Lin^1*, Goh Yee Ling¹, Phung Dac Cam²

¹Microbiology Division, Institute of Biological Science, Faculty of Science, University of Malaya, Malaysia
²Department of Microbiology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam.

Abstract.

Pulsed-field gel electrophoresis (PFGE) was applied to analyse sporadic and outbreak cases of cholera caused by V. cholerae O1 biotype El Tor from Vietnam (n=16) and V. cholerae O139 from Malaysia (n=12) and from five vaccine strains. NotI-Digestion of chromosomal DNA from these isolates, followed by PFGE produced eleven different profiles among the 16 V. cholerae O1 isolates (Dice coefficient: 0.67-0.97). The V. cholerae O1 Ogawa and Inaba strains were clearly differentiated into distinct clusters. NotI-PFGE analysis among V. cholerae O139 isolates showed a predominant PFGE profile (N12) indicating that the outbreak was probably derived a single clone. Among the five vaccine strains, the PFGE profiles of V. cholerae Inaba Cairo 48 and classical Inaba Cairo 48 were similar to some of the field isolates of 01 Inaba strains in Vietnam. The PFGE analysis showed that the V. cholerae 0139 isolates from Malaysia were indistinguishable as these strains were probably derived from a cholera outbreak and the V. cholerae O1 isolates from Vietnam exhibited limited genetic diversity.

Keywords: PFGE, Vibrio cholerae O1 and O139

^*Author for Correspondence.
Mailing address: Microbiology Division, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
Tel No. 603-79674437  Fax No 603-79674606  Email: thongkl@um.edu.my