Plasticity in the purine-thiamine metabolic network of Salmonella

Genetics. 2011 Feb;187(2):623-31. doi: 10.1534/genetics.110.124362. Epub 2010 Dec 6.


In Salmonella enterica, 5-aminoimidazole ribonucleotide (AIR) is the precursor of the 4-amino-5-hydroxymethyl-2-methylpyrimidine (HMP) pyrophosphate moiety of thiamine and the last intermediate in the common HMP/purine biosynthetic pathway. AIR is synthesized de novo via five reactions catalyzed by the purF, -D, -T, -G, and -I gene products. In vivo genetic analysis demonstrated that in the absence of these gene products AIR can be generated if (i) methionine and lysine are in the growth medium, (ii) PurC is functional, and (iii) 5-amino-4-imidazolecarboxamide ribotide (AICAR) has accumulated. This study provides evidence that the five steps of the common HMP/purine biosynthetic pathway can be bypassed in the synthesis of AIR and thus demonstrates that thiamine synthesis can be uncoupled from the early purine biosynthetic pathway in bacteria.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoimidazole Carboxamide / analogs & derivatives
  • Aminoimidazole Carboxamide / metabolism
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Histidine / metabolism
  • Hydroxymethyl and Formyl Transferases / genetics
  • Hydroxymethyl and Formyl Transferases / metabolism
  • Metabolic Networks and Pathways / genetics*
  • Multienzyme Complexes / genetics
  • Multienzyme Complexes / metabolism
  • Mutation
  • Nucleotide Deaminases / genetics
  • Nucleotide Deaminases / metabolism
  • Pentose Phosphate Pathway / genetics
  • Purines / metabolism*
  • Ribonucleotides / metabolism
  • Salmonella enterica / genetics*
  • Salmonella enterica / metabolism*
  • Thiamine / metabolism*


  • Bacterial Proteins
  • Multienzyme Complexes
  • Purines
  • Ribonucleotides
  • inosine monophosphate synthase
  • Aminoimidazole Carboxamide
  • Histidine
  • Hydroxymethyl and Formyl Transferases
  • Nucleotide Deaminases
  • AICA ribonucleotide
  • Thiamine