Extragenic suppression of the requirement for diaminopimelate in diaminopimelate auxotrophs of Mycobacterium smegmatis

FEMS Microbiol Lett. 2003 Aug 8;225(1):131-5. doi: 10.1016/S0378-1097(03)00502-0.


Mycobacteria, like many prokaryotes, have a peptidoglycan with peptides composed of L-alanine (or glycine), D-iso-glutamine, meso-diaminopimelate, and D-alanine. We sought to study mycobacterial peptidoglycan biosynthesis by constructing diaminopimelate (DAP) auxotrophs of Mycobacterium smegmatis and then isolating spontaneous mutants of these auxotrophs that can grow in the absence of DAP. Here we report the isolation and characterization of seven classes of spontaneous M. smegmatis mutants with extragenic mutations that can suppress the DAP requirement of DAP auxotrophs.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acids / metabolism
  • Bacterial Proteins / biosynthesis
  • Diaminopimelic Acid / metabolism*
  • Mutation
  • Mycobacterium smegmatis / genetics*
  • Mycobacterium smegmatis / growth & development
  • Mycobacterium smegmatis / metabolism*
  • Peptidoglycan / biosynthesis
  • Suppression, Genetic


  • Amino Acids
  • Bacterial Proteins
  • Peptidoglycan
  • Diaminopimelic Acid