Tehran University of Medical Sciences Iranian Journal of Microbiology 2008-3289 2 4 2010 12 15 194 197 EN H Goudarzi Department of Microbiology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. ES Mirsamadi Department of Microbiology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran AND Mycobacterium Research Center (MRC) National Research Institute of Tuberculosis and Lung Disease (NRITLD), Tehran, Iran. S Jahani Sherafat Department of Microbiology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran AND Mycobacterium Research Center (MRC) National Research Institute of Tuberculosis and Lung Disease (NRITLD), Tehran, Iran. M Esfahani School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. N Faramarzi School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. P Farnia Mycobacterium Research Center (MRC) National Research Institute of Tuberculosis and Lung Disease (NRITLD), Tehran, Iran. 2015 10 01 Background and Objectives: Phospholipase of Mycobacterium tuberculosis plays an important role in pathogenesis through breaking up phospholipids and production of diacylglycerol. In this study, we examined the Beijing strains of Mycobacterium tuberculosis isolated from Iranian patients for the genes encoding this enzyme. Materials and Methods: DNA extraction was performed using CTAB (cetyltrimethylammonium bromide) from positive culture specimens in tuberculosis patients. PCR was then used to amplify the plcA, plcB, plcC genes of Beijing strain, and non-Beijing strains were identified by spoligotyping. Results: Of 200 specimens, 19 (9.5%) were Beijing strain and 181 (90.5%) were non-Beijing strains. The results of PCR for Beijing strains were as follows: 16 strains (84.2%) were positive for plcA, 17 (89.4%) were positive for plcB and 17 (89.4%) were positive for plcC genes. The standard strain (H37RV) was used as control. Conclusion: The majority of Beijing strains have phospholipase C genes which can contribute to their pathogenesis but we need complementary studies to confirm the role of phospholipase C in pathogenecity of Mycobacterium tuberculosis. https://ijm.tums.ac.ir/index.php/ijm/article/view/71 https://ijm.tums.ac.ir/index.php/ijm/article/download/71/71