1.Detection of cholera toxin (ctxA and ctxAB) genes in Vibrio cholerae isolated from clinical and environmental samples in Limbang Sarawak by multiplex polymerase chain reaction (PCR)
Amirah Zakirah Ja&rsquo ; afar ; Elexson Nillian ; Lesley Maurice Bilung ; Grace Bebey ; Diyana Zakaria ; Patrick Guda Benjamin
Malaysian Journal of Microbiology 2021;17(1):20-27
Aims:
Cholera epidemics have been occurred in Malaysia since 1991 till 2003 which can be proved from the records by
the Infectious Diseases Division of the Ministry of Health. Moreover, there were also course of cholera epidemics from
the year 1994 to 2003 which had been happened in Sarawak. Cholera outbreaks in Malaysia mostly caused by the El
Tor O1 Vibrio cholerae serogroup. The aims of this study were to detect the presence of V. cholerae in clinical and
environmental samples (n=28) from Limbang, Sarawak by collaboration with Sarawak Government Hospital and to
detect the toxin genes from the isolates.
Methodology and results:
All the isolates were sub-cultured in alkaline peptone water (APW). The boiled-cell method
was used for DNA extraction. The total DNA extracted was amplified by polymerase chain reaction (PCR). Two types of
PCR were used in this study which are 16S rRNA PCR and multiplex PCR. The results obtained from the study found
out that 16 out of 28 (57.14%) samples were confirmed to be V. cholerae species. Four primers specific for V. cholerae
were used in multiplex PCR (O1 type, O139 type, ctxA and ctxAB) to confirm the species type and the toxin genes. All
samples shown positive for V. cholerae O1 serotype and 100% positive to all genes for the identification of ctxA and
ctxAB genes.
Conclusion, significance and impact of study
From this study, it showed that multiplex PCR can be used for
research purposes in molecular genetics field involving cholera outbreak.
Vibrio cholerae--genetics
;
Cholera Toxin