2R7K

Crystal structure of FAICAR synthetase (PurP) from M. jannaschii complexed with AMPPCP and AICAR

2R7K の概要

• エントリーDOI: 10.2210/pdb2r7k/pdb
• 関連するPDBエントリー: 2R7L 2R7M 2R7N
• 分子名称: 5-formaminoimidazole-4-carboxamide-1-(beta)-D-ribofuranosyl 5'-monophosphate synthetase, SULFATE ION, CHLORIDE ION, ... (6 entities in total)
• 機能のキーワード: atp-grasp superfamily, atp-binding, ligase, magnesium, manganese, metal-binding, nucleotide-binding
• 由来する生物種: Methanocaldococcus jannaschii
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 41884.37

構造登録者

Zhang, Y.,White, R.H.,Ealick, S.E. (登録日: 2007-09-09, 公開日: 2007-12-04, 最終更新日: 2024-02-21)

主引用文献

Zhang, Y.,White, R.H.,Ealick, S.E.
Crystal structure and function of 5-formaminoimidazole-4-carboxamide ribonucleotide synthetase from Methanocaldococcus jannaschii.
Biochemistry, 47:205-217, 2008

PubMed Abstract: Purine biosynthesis requires 10 enzymatic steps in higher organisms, while prokaryotes require an additional enzyme for step 6. In most organisms steps 9 and 10 are catalyzed by the purH gene product, a bifunctional enzyme with both 5-formaminoimidazole-4-carboxamide ribonucleotide (FAICAR) synthase and inosine monophosphate (IMP) cyclohydrolase activity. Recently it was discovered that Archaea utilize different enzymes to catalyze steps 9 and 10. An ATP-dependent FAICAR synthetase is encoded by the purP gene, and IMP cyclohydrolase is encoded by the purO gene. We have determined the X-ray crystal structures of FAICAR synthetase from Methanocaldococcus jannaschii complexed with various ligands, including the tertiary substrate complex and product complex. The enzyme belongs to the ATP grasp superfamily and is predicted to use a formyl phosphate intermediate formed by an ATP-dependent phosphorylation. In addition, we have determined the structures of a PurP orthologue from Pyrococcus furiosus, which is functionally unclassified, in three crystal forms. With approximately 50% sequence identity, P. furiosus PurP is structurally homologous to M. jannaschii PurP. A phylogenetic analysis was performed to explore the possible role of this functionally unclassified PurP.

PubMed: 18069798
DOI: 10.1021/bi701406g

実験手法

X-RAY DIFFRACTION (2.1 Å)