1SPI

CRYSTAL STRUCTURE OF SPINACH CHLOROPLAST FRUCTOSE-1,6-BISPHOSPHATASE AT 2.8 ANGSTROMS RESOLUTION

1SPI の概要

• エントリーDOI: 10.2210/pdb1spi/pdb
• 分子名称: FRUCTOSE 1,6-BISPHOSPHATASE (1 entity in total)
• 機能のキーワード: hydrolase (phosphoric monoester)
• 由来する生物種: Spinacia oleracea (spinach)
• 細胞内の位置: Plastid, chloroplast: P22418
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 156724.50

構造登録者

Villeret, V.,Huang, S.,Zhang, Y.,Xue, Y.,Lipscomb, W.N. (登録日: 1994-12-14, 公開日: 1995-02-27, 最終更新日: 2024-02-14)

主引用文献

Villeret, V.,Huang, S.,Zhang, Y.,Xue, Y.,Lipscomb, W.N.
Crystal structure of spinach chloroplast fructose-1,6-bisphosphatase at 2.8 A resolution.
Biochemistry, 34:4299-4306, 1995

PubMed Abstract: The three-dimensional structure of the spinach chloroplast fructose-1,6-bisphosphatase (Fru-1,6-Pase) has been solved by the molecular replacement method at 2.8 A resolution and refined to a crystallographic R factor of 0.203. The enzyme is composed of four monomers and displays pseudo D2 symmetry. Comparison with the allosteric Fru-1,6-Pase from pig kidney shows orientationally displaced dimers within the quaternary structure of the chloroplast enzyme. When the C1C2 dimers of the two enzymes are superimposed, the C3C4 dimer of the chloroplast enzyme is rotated 20 degrees and 5 degrees relative to the C3C4 dimer of the R and T forms of the pig kidney enzyme, respectively. This new quaternary structure, designated as S, may be described as a super-T form and is outside of the pathway of the allosteric transition which occurs in the pig kidney enzyme, which shows a 15 degrees rotation between T and R forms. Chloroplast Fru-1,6-Pase, unlike the pig kidney enzyme, is insensitive to allosteric transformation by AMP. Structural changes in the AMP binding site involving mainly helices H1, H2, and H3 and the loop between H1 and H2 at the dimer interface interfere with binding of the phosphate of AMP. Finally, the location of cysteines residues provides a basis for a preliminary discussion of the activation of the enzyme by reduction of cysteines via the ferredoxin-thioredoxin f system; this process is complementary to activation by pH changes, Mg2+ or Ca2+, Fru-1,6-P2, and possibly Fru-2,6-P2.

PubMed: 7703243
DOI: 10.1021/bi00013a019

実験手法

X-RAY DIFFRACTION (2.8 Å)