6-Pyruvoyltetrahydropterin synthase orthologs of either a single or dual domain structure are responsible for tetrahydrobiopterin synthesis in bacteria

FEBS Lett. 2006 Sep 4;580(20):4900-4. doi: 10.1016/j.febslet.2006.08.006. Epub 2006 Aug 14.


6-Pyruvoyltetrahydropterin synthase (PTPS) catalyzes the second step of tetrahydrobiopterin (BH4) synthesis. We previously identified PTPS orthologs (bPTPS-Is) in bacteria which do not produce BH4. In this study we disrupted the gene encoding bPTPS-I in Synechococcus sp. PCC 7942, which produces BH4-glucoside. The mutant was normal in BH4-glucoside production, demonstrating that bPTPS-I does not participate in BH4 synthesis in vivo and bringing us a new PTPS ortholog (bPTPS-II) of a bimodular polypeptide. The recombinant Synechococcus bPTPS-II was assayed in vitro to show PTPS activity higher than human enzyme. Further computational analysis revealed the presence of mono and bimodular bPTPS-II orthologs mostly in green sulfur bacteria and cyanobacteria, respectively, which are well known for BH4-glycoside production. In summary we found new bacterial PTPS orthologs, having either a single or dual domain structure and being responsible for BH4 synthesis in vivo, thereby disclosing all the bacterial PTPS homologs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / classification
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Biopterin / analogs & derivatives*
  • Biopterin / biosynthesis
  • Humans
  • Isoenzymes / chemistry*
  • Isoenzymes / classification
  • Isoenzymes / genetics
  • Isoenzymes / metabolism*
  • Molecular Sequence Data
  • Mutagenesis
  • Phosphorus-Oxygen Lyases / chemistry*
  • Phosphorus-Oxygen Lyases / classification
  • Phosphorus-Oxygen Lyases / genetics
  • Phosphorus-Oxygen Lyases / metabolism*
  • Phylogeny
  • Protein Conformation
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / classification
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Sequence Alignment
  • Synechococcus / genetics
  • Synechococcus / metabolism


  • Bacterial Proteins
  • Isoenzymes
  • Recombinant Proteins
  • Biopterin
  • Phosphorus-Oxygen Lyases
  • 6-pyruvoyltetrahydropterin synthase
  • sapropterin