Mycobacterium Lysine ε-aminotransferase is a novel alarmone metabolism related persister gene via dysregulating the intracellular amino acid level

Sci Rep. 2016 Jan 25:6:19695. doi: 10.1038/srep19695.

Abstract

Bacterial persisters, usually slow-growing, non-replicating cells highly tolerant to antibiotics, play a crucial role contributing to the recalcitrance of chronic infections and treatment failure. Understanding the molecular mechanism of persister cells formation and maintenance would obviously inspire the discovery of new antibiotics. The significant upregulation of Mycobacterium tuberculosis Rv3290c, a highly conserved mycobacterial lysine ε-aminotransferase (LAT) during hypoxia persistent model, suggested a role of LAT in persistence. To test this, a lat deleted Mycobacterium smegmatis was constructed. The expression of transcriptional regulator leucine-responsive regulatory protein (LrpA) and the amino acids abundance in M. smegmatis lat deletion mutants were lowered. Thus, the persistence capacity of the deletion mutant was impaired upon norfloxacin exposure under nutrient starvation. In summary, our study firstly reported the involvement of mycobacterium LAT in persister formation, and possibly through altering the intracellular amino acid metabolism balance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / metabolism*
  • Antitubercular Agents / pharmacology
  • Drug Resistance, Bacterial
  • Gene Deletion
  • Gene Knockout Techniques
  • Gene Order
  • Genetic Loci
  • Intracellular Space
  • L-Lysine 6-Transaminase / genetics*
  • L-Lysine 6-Transaminase / metabolism*
  • Microbial Viability / drug effects
  • Microbial Viability / genetics
  • Mutation
  • Mycobacterium / drug effects
  • Mycobacterium / genetics*
  • Mycobacterium / metabolism*
  • Mycobacterium smegmatis / genetics
  • Mycobacterium smegmatis / metabolism
  • Norfloxacin / pharmacology

Substances

  • Amino Acids
  • Antitubercular Agents
  • L-Lysine 6-Transaminase
  • Norfloxacin