Mycobacterium tuberculosis Rv1515c antigen enhances survival of M. smegmatis within macrophages by disrupting the host defence.

Affiliation

Yang W(1), Liu M(1), Yu X(1), Huang Y(1), Zeng J(1), Dai Y(1), Luo H(1), Huang Q(1), Fan L(2), Xie J(3).
Author information:
(1)State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Institute of Modern Biopharmaceuticals, Southwest University, Chongqing, China.
(2)Shanghai Clinic and Research Center of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai Key Laboratory of Tuberculosis, Shanghai, 200433, China. Electronic address: [Email]
(3)State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Institute of Modern Biopharmaceuticals, Southwest University, Chongqing, China. Electronic address: [Email]

Abstract

Mycobacterium tuberculosis (Mtb) infection is the major cause of tuberculosis. Mtb regions of difference (RD) genes are vital for survival of the pathogen within hosts and for the attenuation of the bacillus Calmette-Guérin vaccine. However, the function of most RD proteins largely remains unexplored. In the present study, we focused on Rv1515c, an RD6 member from M. tuberculosis, and characterised it as a cell surface-associated protein that functions in disrupting the cytokine profile and promoting endoplasmic reticulum stress-mediated apoptosis. Rv1515c expression in M. smegmatis, a nonpathogenic species, resulted in enhanced resistance of the bacterium to various in vitro stressors (such as low pH, sodium dodecyl sulfate, oxidative pressure, and nitrogen intermediate) and its cellular survival within macrophages. Our study is the first to identify the role of Rv1515c in the physiology and pathogenesis of mycobacterium.