African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5233

Full Length Research Paper

Two methods for extraction of high-purity genomic DNA from mucoid Gram-negative bacteria

Xiao Xiao1, Jingling Zhang1,2, Quanyi Zhang1, Li Wang1,2, Yafang Tan1, Zhaobiao Guo1, Ruifu Yang1, Jingfu Qiu2 and Dongsheng Zhou1*
1State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China. 2School of Public Health, Chongqing Medical University, Chongqing 400016, China.
Email: [email protected]

  •  Accepted: 13 September 2011
  •  Published: 23 October 2011



Due to the production of abundant capsular polysaccharides and or exopolysaccharides, some bacteria form mucoid and opaque colonies on solid agar medium. Polysaccharides interfere with the isolation and characterization of DNA. Extraction of polysaccharide-free DNA from the mucoid bacteria is required for genetic and biochemical studies. In this study, mucoid Vibrio parahaemolyticus and Klebsiella pneumonia were used as model organisms for comparing the effectiveness of two DNA extraction methods. The two methods were proved reproducible and cost-effective for extracting high-purity genome DNA from mucoid bacteria for further applications.


Key words: Mucoid bacteria, Vibrio parahaemolyticusKlebsiella pneumonia, DNA isolation, polysaccharides.