6-Pyruvoyltetrahydropterin synthase orthologs of either a single or dual domain structure are responsible for tetrahydrobiopterin synthesis in bacteria.
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.
Kong
Jin Sun
JS
Mitochondrial Research Group, School of Biotechnology and Biomedical Science, Inje University, Kimhae 621-749, Republic of Korea.
Kang
Ji-Youn
JY
Kim
Hye Lim
HL
Kwon
O-Seob
OS
Lee
Kon Ho
KH
Park
Young Shik
YS
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D001708:Biopterins / Q000031:analogs & derivatives* / Q000096:biosynthesis; D006801:Humans; D007527:Isoenzymes / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016296:Mutagenesis; D019761:Phosphorus-Oxygen Lyases / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D046940:Synechococcus / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D007527:Isoenzymes; D011994:Recombinant Proteins; D001708:Biopterins; D019761:Phosphorus-Oxygen Lyases; C043497:6-pyruvoyltetrahydropterin synthase; C003402:sapropterin