The Mycobacterium Tuberculosis Purine Biosynthetic Pathway: Isolation and Characterization of the purC and purL Genes

Microbiology. 1996 Sep;142 ( Pt 9):2439-47. doi: 10.1099/00221287-142-9-2439.


Genes from the Mycobacterium tuberculosis purine biosynthetic pathway were identified using purine auxotrophic mutants of Mycobacterium smegmatis obtained by Tn611 transposon mutagenesis. Two approaches were followed in parallel. The first consisted of the complementation of the M. smegmatis purine auxotrophs using a M. tuberculosis H37Rv shuttle cosmid library. In the second approach, specific probes corresponding to the regions adjacent to the insertion sites of Tn611 in the M. smegmatis genome were used to screen a M. tuberculosis plasmid library by colony hybridization for inserts carrying homologous DNA fragments. Nucleotide sequence analysis of two M. tuberculosis genes isolated by these methods revealed high similarities with purC and purL genes from other bacterial and fungal sources. Transcriptional start sites were mapped for both genes, which revealed similar-10 boxes but with a higher GC content than the Escherichia coli sigma 70 consensus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / genetics*
  • Base Sequence
  • Blotting, Southern
  • Carbon-Nitrogen Ligases with Glutamine as Amide-N-Donor*
  • Cloning, Molecular
  • Cosmids
  • DNA Transposable Elements / genetics
  • Escherichia coli Proteins*
  • Gene Expression Regulation, Bacterial
  • Gene Library
  • Genetic Complementation Test
  • Ligases*
  • Molecular Sequence Data
  • Mutagenesis, Insertional
  • Mycobacterium / genetics
  • Mycobacterium tuberculosis / genetics*
  • Nucleic Acid Hybridization
  • Peptide Synthases*
  • Polymerase Chain Reaction
  • Transcription, Genetic


  • Bacterial Proteins
  • DNA Transposable Elements
  • Escherichia coli Proteins
  • Ligases
  • Peptide Synthases
  • PurC protein, Bacteria
  • Carbon-Nitrogen Ligases with Glutamine as Amide-N-Donor
  • PurL protein, E coli

Associated data

  • GENBANK/U34956
  • GENBANK/U34957