5IZ3

P. patens sedoheptulose-1,7-bisphosphatase

5IZ3 の概要

• エントリーDOI: 10.2210/pdb5iz3/pdb
• 分子名称: sedoheptulose-1,7-bisphosphatase, Predicted protein, IMIDAZOLE, ... (5 entities in total)
• 機能のキーワード: physcomitrella patens carbon metabolism sedoheptulose bisphophatase, hydrolase
• 由来する生物種: Physcomitrella patens (Moss); 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 69668.36

構造登録者

Einsle, O.,Guetle, D. (登録日: 2016-03-24, 公開日: 2016-06-08, 最終更新日: 2024-11-20)

主引用文献

Gutle, D.D.,Roret, T.,Muller, S.J.,Couturier, J.,Lemaire, S.D.,Hecker, A.,Dhalleine, T.,Buchanan, B.B.,Reski, R.,Einsle, O.,Jacquot, J.P.
Chloroplast FBPase and SBPase are thioredoxin-linked enzymes with similar architecture but different evolutionary histories.
Proc.Natl.Acad.Sci.USA, 113:6779-6784, 2016

PubMed Abstract: The Calvin-Benson cycle of carbon dioxide fixation in chloroplasts is controlled by light-dependent redox reactions that target specific enzymes. Of the regulatory members of the cycle, our knowledge of sedoheptulose-1,7-bisphosphatase (SBPase) is particularly scanty, despite growing evidence for its importance and link to plant productivity. To help fill this gap, we have purified, crystallized, and characterized the recombinant form of the enzyme together with the better studied fructose-1,6-bisphosphatase (FBPase), in both cases from the moss Physcomitrella patens (Pp). Overall, the moss enzymes resembled their counterparts from seed plants, including oligomeric organization-PpSBPase is a dimer, and PpFBPase is a tetramer. The two phosphatases showed striking structural homology to each other, differing primarily in their solvent-exposed surface areas in a manner accounting for their specificity for seven-carbon (sedoheptulose) and six-carbon (fructose) sugar bisphosphate substrates. The two enzymes had a similar redox potential for their regulatory redox-active disulfides (-310 mV for PpSBPase vs. -290 mV for PpFBPase), requirement for Mg(2+) and thioredoxin (TRX) specificity (TRX f > TRX m). Previously known to differ in the position and sequence of their regulatory cysteines, the enzymes unexpectedly showed unique evolutionary histories. The FBPase gene originated in bacteria in conjunction with the endosymbiotic event giving rise to mitochondria, whereas SBPase arose from an archaeal gene resident in the eukaryotic host. These findings raise the question of how enzymes with such different evolutionary origins achieved structural similarity and adapted to control by the same light-dependent photosynthetic mechanism-namely ferredoxin, ferredoxin-thioredoxin reductase, and thioredoxin.

PubMed: 27226308
DOI: 10.1073/pnas.1606241113

実験手法

X-RAY DIFFRACTION (1.3 Å)