1DCU

REDOX SIGNALING IN THE CHLOROPLAST: STRUCTURE OF OXIDIZED PEA FRUCTOSE-1,6-BISPHOSPHATE PHOSPHATASE

1DCU の概要

• エントリーDOI: 10.2210/pdb1dcu/pdb
• 関連するPDBエントリー: 1D9Q 1DBZ
• 分子名称: FRUCTOSE-1,6-BISPHOSPHATASE (2 entities in total)
• 機能のキーワード: chloroplast, photosynthesis, redox regulation, thioredoxin, allostery, hydrolase
• 由来する生物種: Pisum sativum (pea)
• 細胞内の位置: Plastid, chloroplast stroma: P46275
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 156968.11

構造登録者

Chiadmi, M.,Navaza, A.,Miginiac-Maslow, M.,Jacquot, J.P.,Cherfils, J. (登録日: 1999-11-05, 公開日: 1999-12-03, 最終更新日: 2024-10-16)

主引用文献

Chiadmi, M.,Navaza, A.,Miginiac-Maslow, M.,Jacquot, J.P.,Cherfils, J.
Redox signalling in the chloroplast: structure of oxidized pea fructose-1,6-bisphosphate phosphatase.
EMBO J., 18:6809-6815, 1999

PubMed Abstract: Sunlight provides the energy source for the assimilation of carbon dioxide by photosynthesis, but it also provides regulatory signals that switch on specific sets of enzymes involved in the alternation of light and dark metabolisms in chloroplasts. Capture of photons by chlorophyll pigments triggers redox cascades that ultimately activate target enzymes via the reduction of regulatory disulfide bridges by thioredoxins. Here we report the structure of the oxidized, low-activity form of chloroplastic fructose-1, 6-bisphosphate phosphatase (FBPase), one of the four enzymes of the Calvin cycle whose activity is redox-regulated by light. The regulation is of allosteric nature, with a disulfide bridge promoting the disruption of the catalytic site across a distance of 20 A. Unexpectedly, regulation of plant FBPases by thiol-disulfide interchange differs in every respect from the regulation of mammalian gluconeogenic FBPases by AMP. We also report a second crystal form of oxidized FBPase whose tetrameric structure departs markedly from D(2) symmetry, a rare event in oligomeric structures, and the structure of a constitutively active mutant that is unable to form the regulatory disulfide bridge. Altogether, these structures provide a structural basis for redox regulation in the chloroplast.

PubMed: 10581254
DOI: 10.1093/emboj/18.23.6809

実験手法

X-RAY DIFFRACTION (2.2 Å)