title: NapM, a new nucleoid-associated protein, broadly regulates gene expression and affects mycobacterial resistance to anti-tuberculosis drugs.
abstract: Nucleoid-associated proteins (NAPs) play important roles in the global organization of bacterial chromosomes. However, potential NAPs and their functions are barely characterized in mycobacteria. In this study, NapM, an alkaline protein, functions as a new NAP. NapM is conserved in all of the sequenced mycobacterial genomes, and can recognize DNA in a length-dependent but sequence-independent manner. It prefers AT-rich DNA and binds to the major groove. NapM possesses a clear DNA-bridging function, and can protect DNA from DNase I digestion. NapM globally regulates the expression of more than 150 genes and the resistance of Mycobacterium smegmatis to two anti-tuberculosis drugs, namely, rifampicin and ethambutol. An ABC transporter operon was found to be specifically responsible for the napM-dependent ethambutol resistance of M. smegmatis. NapM also presents a similar regulation of anti-tuberculosis drug resistance in M. tuberculosis. These results suggest that NapM is a new member of the mycobacterial NAP family. Our findings expand the range of identified NAPs and improve the understanding on the relationship between NAPs with antibiotic resistance in mycobacteria.
authors.affiliation: National Key Laboratory of Agricultural Microbiology, Department of Biological Science, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: National Key Laboratory of Agricultural Microbiology, Department of Biological Science, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Hongyang
authors.initials: H
authors.lastname: Wang
authors.affiliation: National Key Laboratory of Agricultural Microbiology, Department of Biological Science, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Cui
authors.affiliation: National Key Laboratory of Agricultural Microbiology, Department of Biological Science, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Xiling
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Division of Biological Imaging, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Jia
authors.affiliation: National Key Laboratory of Agricultural Microbiology, Department of Biological Science, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.affiliation: National Key Laboratory of Agricultural Microbiology, Department of Biological Science, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Zheng-Guo
authors.initials: ZG
authors.lastname: He
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D000995:Antitubercular Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004352:Drug Resistance, Microbial; D015870:Gene Expression; D015964:Gene Expression Regulation, Bacterial; D009161:Mycobacterium / Q000187:drug effects / Q000235:genetics*; D020102:Mycobacterium smegmatis / Q000235:genetics; D009169:Mycobacterium tuberculosis / Q000235:genetics; D009876:Operon / Q000235:genetics; D014376:Tuberculosis / Q000188:drug therapy / Q000382:microbiology
chemical_list: D018528:ATP-Binding Cassette Transporters; D000995:Antitubercular Agents; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D004247:DNA