The gene fmt, encoding tRNAfMet-formyl transferase, is essential for normal growth of M. bovis, but not for viability. Issue 1 (December 2017)

• Record Type: Journal Article
• Authors: Vanunu, Miriam; Lang, Ziv; Barkan, Daniel
• Is Part Of: Scientific reports. Volume 7:Issue 1(2017)
• Page Start: 1
• Page End: 8
• Publication Date: 2017-12
• Subjects: Natural history -- Research -- Periodicals; Biology -- Research -- Periodicals; Physical sciences -- Research -- Periodicals; Earth sciences -- Research -- Periodicals; Environmental sciences -- Research -- Periodicals; 502.85
• DOI: 10.1038/s41598-017-15618-9
• Languages: English
• ISSNs: 2045-2322

Abstract

Abstract Mycobacterium tuberculosis is a major health threat, necessitating novel drug targets. Protein synthesis in bacteria uses initiator tRNAi charged with formylated methionine residue. Deletion of the formylase gene, tRNAfMet -formyl transferase (fmt ), causes severe growth-retardation inE .coli and inS .pneumoniae, but not inP .aeruginosa orS .aureus .fmt was predicted to be essential inM .tuberculosis by transposon library analysis, but this was never formally tested in any mycobacteria. We performed a targeted deletion offmt inM .smegmatis as well as Mtb-complex (M .bovis ). In both cases, we created a mero-diploid strain, deleted the native gene by two-step allelic exchange or specialized-phage transduction, and then removed the complementing gene to create full deletion mutants. InM .smegmatis a full deletion strain could be easily created. In contrast, inM .bovis -BCG, a full deletion strain could only be created after incubation of 6 weeks, with a generation time ~2 times longer than for wt bacteria. Our results confirm the importance of this gene in pathogenic mycobacteria, but as the deletion mutant is viable, validity offmt as a drug target remains unclear. Our results also refute the previous reports thatfmt is essential inM .tuberculosis -complex.