Rasana W Sermswan1, Phairat Royros2, Nittaya Khakhum2, Surasakdi Wongratanacheewin3, Apichai Tuanyok4. 1. Department of Biochemistry, Faculty of Medicine, Khon Kean University, 123 Mitraparp Rd, Khon Kaen 40002, Thailand Melioidosis Research Center, Faculty of Medicine, Khon Kean University, Khon Kaen, Thailand rasana@kku.ac.th. 2. Department of Biochemistry, Faculty of Medicine, Khon Kean University, 123 Mitraparp Rd, Khon Kaen 40002, Thailand Melioidosis Research Center, Faculty of Medicine, Khon Kean University, Khon Kaen, Thailand. 3. Melioidosis Research Center, Faculty of Medicine, Khon Kean University, Khon Kaen, Thailand Department of Microbiology, Faculty of Medicine, Khon Kean University, Khon Kaen, Thailand. 4. Department of Infectious Diseases and Pathology, University of Florida, Gainesville, Florida, USA.
Abstract
BACKGROUND: Burkholderia pseudomallei, a Gram-negative saprophytic bacillus, is a severe infectious agent that causes melioidosis and soil is the most important reservoir. METHODS: One hundred and forty soil samples were tested for pH, moisture content and total C and N measurements and used for DNA extraction and culture for B. pseudomallei. The quantitative real-time PCR (qPCR) targeting wcbG, a putative capsular polysaccharide biosynthesis protein gene of B. pseudomallei, was developed to detect the bacterium, and random amplified polymorphic DNA (RAPD) was used to detect the microbial diversity in soil. RESULTS: The acidic pH was correlated with the presence of the bacterium. Forty-four soil sites (44/140, 31.4%) were positive for B. pseudomallei by qPCR, of which 21 were positive by culture. The limit of detection is 32 fg of DNA (about 4 genomes). The RAPD method could classify the soil samples into low diversity (LD) and high diversity (HD) sites. The trend of LD was found with B. pseudomallei positive soil sites. CONCLUSIONS: The acidity of the soil or metabolites from organisms in the sites may contribute to the presence of the bacterium. Further investigation of microbes by a more robust method should elucidate biological factors that promote the presence of B. pseudomallei and may be used for controlling the bacterium in the environment.
BACKGROUND: Burkholderia pseudomallei, a Gram-negative saprophytic bacillus, is a severe infectious agent that causes melioidosis and soil is the most important reservoir. METHODS: One hundred and forty soil samples were tested for pH, moisture content and total C and N measurements and used for DNA extraction and culture for B. pseudomallei. The quantitative real-time PCR (qPCR) targeting wcbG, a putative capsular polysaccharide biosynthesis protein gene of B. pseudomallei, was developed to detect the bacterium, and random amplified polymorphic DNA (RAPD) was used to detect the microbial diversity in soil. RESULTS: The acidic pH was correlated with the presence of the bacterium. Forty-four soil sites (44/140, 31.4%) were positive for B. pseudomallei by qPCR, of which 21 were positive by culture. The limit of detection is 32 fg of DNA (about 4 genomes). The RAPD method could classify the soil samples into low diversity (LD) and high diversity (HD) sites. The trend of LD was found with B. pseudomallei positive soil sites. CONCLUSIONS: The acidity of the soil or metabolites from organisms in the sites may contribute to the presence of the bacterium. Further investigation of microbes by a more robust method should elucidate biological factors that promote the presence of B. pseudomallei and may be used for controlling the bacterium in the environment.
Authors: L Manivanh; A Pierret; S Rattanavong; O Kounnavongsa; Y Buisson; I Elliott; J L Maeght; K Xayyathip; J Silisouk; M Vongsouvath; R Phetsouvanh; P N Newton; G Lacombe; O Ribolzi; E Rochelle-Newall; D A B Dance Journal: Sci Rep Date: 2017-06-08 Impact factor: 4.379
Authors: David A B Dance; Michael Knappik; Sabine Dittrich; Viengmon Davong; Joy Silisouk; Manivanh Vongsouvath; Sayaphet Rattanavong; Alain Pierret; Paul N Newton; Premjit Amornchai; Vanaporn Wuthiekanun; Sayan Langla; Direk Limmathurotsakul Journal: Wellcome Open Res Date: 2018-11-21