2ABW

Glutaminase subunit of the plasmodial PLP synthase (Vitamin B6 biosynthesis)

2ABW の概要

• エントリーDOI: 10.2210/pdb2abw/pdb
• 関連するPDBエントリー: 1R9G
• 分子名称: Pdx2 protein, TETRAETHYLENE GLYCOL (3 entities in total)
• 機能のキーワード: glutaminase, plp-synthase, vitamin b6, malaria, transferase
• 由来する生物種: Plasmodium falciparum (malaria parasite P. falciparum)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 51514.89

構造登録者

Gengenbacher, M.,Fitzpatrick, T.B.,Raschle, T.,Flicker, K.,Sinning, I.,Mueller, S.,Macheroux, P.,Tews, I.,Kappes, B. (登録日: 2005-07-17, 公開日: 2006-01-10, 最終更新日: 2023-10-25)

主引用文献

Gengenbacher, M.,Fitzpatrick, T.B.,Raschle, T.,Flicker, K.,Sinning, I.,Mueller, S.,Macheroux, P.,Tews, I.,Kappes, B.
Vitamin B6 Biosynthesis by the Malaria Parasite Plasmodium falciparum: Biochemical and structural insights
J.Biol.Chem., 281:3633-3641, 2006

PubMed Abstract: Vitamin B6 is one of nature's most versatile cofactors. Most organisms synthesize vitamin B6 via a recently discovered pathway employing the proteins Pdx1 and Pdx2. Here we present an in-depth characterization of the respective orthologs from the malaria parasite, Plasmodium falciparum. Expression profiling of Pdx1 and -2 shows that blood-stage parasites indeed possess a functional vitamin B6 de novo biosynthesis. Recombinant Pdx1 and Pdx2 form a complex that functions as a glutamine amidotransferase with Pdx2 as the glutaminase and Pdx1 as pyridoxal-5 '-phosphate synthase domain. Complex formation is required for catalytic activity of either domain. Pdx1 forms a chimeric bi-enzyme with the bacterial YaaE, a Pdx2 ortholog, both in vivo and in vitro, although this chimera does not attain full catalytic activity, emphasizing that species-specific structural features govern the interaction between the protein partners of the PLP synthase complexes in different organisms. To gain insight into the activation mechanism of the parasite bi-enzyme complex, the three-dimensional structure of Pdx2 was determined at 1.62 A. The obstruction of the oxyanion hole indicates that Pdx2 is in a resting state and that activation occurs upon Pdx1-Pdx2 complex formation.

PubMed: 16339145
DOI: 10.1074/jbc.M508696200

実験手法

X-RAY DIFFRACTION (1.62 Å)