title: Down-regulation of N-acetylglucosamine-1-phosphate transferase (WecA) enhanced the sensitivity of Mycobacterium smegmatis against rifampin.
abstract: OBJECTIVE
  To construct a conditional N-acetylglucosamine-1-phosphate transferase (WecA) knockdown strain of Mycobacterium smegmatis and to investigate the biological effect of WecA on mycobacterial growth, morphology and susceptibilities against anti-tuberculosis drugs.
  
  
  RESULTS
  Mycobacterium smegmatis wecA knockdown strain was constructed by using a tetracycline-inducible expression vector pMind and the expression of WecA was regulated by antisense RNA. The results of growth curves and the colony formation unit curves showed that the growth rate of WecA down-regulation strain was decreased and the amount of live bacterial cells dropped. In addition, the wecA knockdown strain exhibited dramatically morphological alterations through scanning electron microscopy observation. The susceptibility of WecA low-expression strain to anti-tuberculosis drugs was detected by using a rapid resazurin microtitre assay as well as a traditional agar dilution method. Notably, the wecA knockdown strain was more sensitive to rifampin, compared with the wecA normal-expression strain. In addition, the sensitivity of wild type Myco. smegmatis mc(2) 155 strain against rifampin was also enhanced in the presence of a low concentration of tunicamycin, a natural WecA inhibitor.
  
  
  CONCLUSIONS
  Down-regulation of WecA enhanced the sensitivity of Myco. smegmatis against rifampin.
  
  
  CONCLUSIONS
  These results provided a possibility of combined application of rifampin together with tunicamycin or other WecA inhibitors, which could be a new approach for the treatment of tuberculosis.
authors.affiliation: Scientific Research Center, The Second Affiliated Hospital of Dalian Medical University, Dalian, China.|Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian, China.
authors.forename: L
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian, China.
authors.forename: L
authors.initials: L
authors.lastname: Qian
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian, China.
authors.forename: J
authors.initials: J
authors.lastname: Kang
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian, China.
authors.forename: S
authors.initials: S
authors.lastname: Sha
authors.affiliation: Department of Biotechnology, Dalian Medical University, Dalian, China.|Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Xin
authors.affiliation: Scientific Research Center, The Second Affiliated Hospital of Dalian Medical University, Dalian, China.
authors.forename: S
authors.initials: S
authors.lastname: Lu
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian, China. yufang_ma@hotmail.com.|Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian, China. yufang_ma@hotmail.com.
authors.forename: Y
authors.initials: Y
authors.lastname: Ma
mesh_terms: D000904:Antibiotics, Antitubercular / Q000494:pharmacology*; D015536:Down-Regulation; D055785:Gene Knockdown Techniques; D006801:Humans; D006967:Hypersensitivity; D020102:Mycobacterium smegmatis / Q000187:drug effects* / Q000201:enzymology / Q000648:ultrastructure; D009169:Mycobacterium tuberculosis / Q000235:genetics; D012293:Rifampin / Q000494:pharmacology*; D017855:Transferases (Other Substituted Phosphate Groups) / Q000037:antagonists & inhibitors*; D014376:Tuberculosis / Q000188:drug therapy / Q000382:microbiology
chemical_list: D000904:Antibiotics, Antitubercular; D017855:Transferases (Other Substituted Phosphate Groups); C023222:UDPacetylglucosamine-dolichyl-phosphate acetylglucosamine-1-phosphate transferase; D012293:Rifampin
keywords: Mycobacterium smegmatis; N-acetylglucosamine-1-phosphate transferase; WecA; antisense RNA; rifampin