Iranian Biomedical Journal

en RNA Expression Analysis of Mycobacterial Methyltransferases Genes in Different Resistant Strains of Mycobacterium tuberculosis Molecular Microbiology Molecular Microbiology مقاله کامل Full Length/Original Article Background: Tuberculosis infection still represents a global health issue affecting patients worldwide. Strategies for its control may be not as effective as it should be, specifically in case of resistant strains of Mycobacterium tuberculosis (M.tb.) In this regard, the role of mycobacterial methyltransferases (MTases) in TB infection can be fundamental, though it has not been broadly deciphered. Methods: Five resistant isolates of M.tb were obtained. M.tb H37Rv (ATCC 27249) was used as a reference strain. Seven putative mycobacterial MTase genes (Rv0645c, Rv2966c, Rv1988, Rv1694, Rv3919c, Rv2756c, and Rv3263) and Rv1392 as SAM synthase were selected for analysis. PCR-sequencing and qRT-PCR were performed to compare mutations and expression levels of MTases in different strains. The 2-ΔΔCt method was employed to calculate the relative expression levels of these genes. Results: Only two mutations were found in isoniazid resistance (INHR) strain for Rv3919c (T to G in codon 341) and Rv1392 (G to A in codon 97) genes. Overexpression of Rv0645c, Rv2756c, Rv3263, and Rv2966c was detected in all sensitive and resistant isolates. However, Rv1988 and Rv3919c decreased and Rv1694 increased in the sensitive strains. The Rv1392 expression level also decreased in INHR isolate. Conclusion: We found a correlation between mycobacterial MTases expression and resistance to antibiotics in M.tb strains. Some MTases undeniably are virulence factors that specifically hijack the host defense mechanism. Further evaluations are needed to explore the complete impact of mycobacterial MTases within specific strains of M.tb to introduce novel diagnosis and treatment strategies. Drug resistance, Methyltransferases, Mycobacterium tuberculosis, S-adenosylmethionine 240 251 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-4682-1&slc_lang=en&sid=1 Samira Tarashi tarashisamira@gmail.com 0000-0002-7141-322X No Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran Mohammad Saber Zamani msaber.ir@gmail.com 0000-0002-4614-6254 No Immunoregulation Research Center, Shahed University, Tehran, Iran Golnaz Bahramali gbahramali@gmail.com 0000-0002-1762-4907 No Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran Andrea Fuso andrea.fuso@uniroma1.it 0000-0001-9467-5671 No Department of Experimental Medicine, Sapienza University of Rome, Italy Farzam Vaziri farzam_vaziri@yahoo.com 0000-0001-7788-2548 No Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran Morteza Karimipoor mortezakarimi@yahoo.com 0000-0002-2406-5963 No Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran Abolfazl Fateh afateh2@gmail.com 0000-0002-2043-5823 No Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran Seyed Davar Siadat d.siadat@gmail.com 0000-0002-6892-5603 Yes Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran