Transcriptional and proteomic analyses of two-component response regulators in multidrug-resistant Mycobacterium tuberculosis.
Two-component systems (TCSs) have been reported to exhibit a sensing and responding role under drug stress that induces drug resistance in several bacterial species. However, the relationship between TCSs and multidrug resistance in Mycobacterium tuberculosis has not been comprehensively analysed to date. In this study, 90 M. tuberculosis clinical isolates were analysed using 15-loci mycobacterial interspersed repetitive unit (MIRU)-variable number tandem repeat (VNTR) typing and repetitive extragenic palindromic (rep)-PCR-based DNA fingerprinting. The results showed that all of the isolates were of the Beijing lineage, and strains with a drug-susceptible phenotype had not diverged into similar genotype clusters. Expression analysis of 13 response regulators of TCSs using real-time PCR and tandem mass spectrometry (MS/MS) proteomic analysis demonstrated that four response regulator genes (devR, mtrA, regX3 and Rv3143) were significantly upregulated in multidrug-resistant (MDR) strains compared with the laboratory strain H37Rv as well as drug-susceptible and isoniazid-monoresistant strains (P<0.05). DNA sequencing revealed that the promoter regions of devR, mtrA, regX3 and Rv3143 did not contain any mutations. Moreover, expression of the four genes could be induced by most of the four first-line antitubercular agents. In addition, either deletion or overexpression of devR in Mycobacterium bovis BCG did not alter its sensitivity to the four antitubercular drugs. This suggests that upregulation of devR, which is common in MDR-TB strains, might be induced by drug stress and hypoxic adaptation following the acquisition of multidrug resistance.
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Lei
L
Zhou
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Liu
L
Yang
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Xianfei
X
Zeng
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Jiacuo
J
Danzheng
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Qing
Q
Zheng
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Jiayun
J
Liu
Institute of Proteomics and System Biology, Fudan University, Shanghai 200433, People's Republic of China.
Feng
F
Liu
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Yijuan
Y
Xin
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Xiaodong
X
Cheng
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China.
Mingquan
M
Su
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China. Electronic address: cmbmayy@fmmu.edu.cn.
Yueyun
Y
Ma
Department of Clinical Laboratory Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shaanxi Province, People's Republic of China. Electronic address: haoxkg@126.com.
Xiaoke
X
Hao
D016172:DNA Fingerprinting; D024901:Drug Resistance, Multiple, Bacterial; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D005838:Genotype; D006801:Humans; D058889:Molecular Typing; D009169:Mycobacterium tuberculosis / Q000737:chemistry* / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D020543:Proteome / Q000032:analysis*; D060888:Real-Time Polymerase Chain Reaction; D053719:Tandem Mass Spectrometry; D014376:Tuberculosis / Q000382:microbiology
D020543:Proteome
Multiple drug resistance; Mycobacterium tuberculosis; Two-component system; devR; mtrA; regX3