PDBsum entry 1spi

Hydrolase (phosphoric monoester)

PDB id: 1spi

Contents

Protein chains

333 a.a. *

* Residue conservation analysis

PDB id:

1spi

Name:

Hydrolase (phosphoric monoester)

Title:

Crystal structure of spinach chloroplast fructose-1,6-bisphosphatase at 2.8 angstroms resolution

Structure:

Fructose 1,6-bisphosphatase. Chain: a, b, c, d. Engineered: yes

Source:

Spinacia oleracea. Spinach. Organism_taxid: 3562

Biol. unit:

Tetramer (from PQS)

Resolution:

2.80Å R-factor: 0.203

Authors:

V.Villeret,S.Huang,Y.Zhang,Y.Xue,W.N.Lipscomb

Key ref:

V.Villeret et al. (1995). Crystal structure of spinach chloroplast fructose-1,6-bisphosphatase at 2.8 A resolution. Biochemistry, 34, 4299-4306. PubMed id: 7703243 DOI: 10.1021/bi00013a019

Date:

14-Dec-94 Release date: 27-Feb-95

Protein chains

P22418  (F16P1_SPIOL) -  Fructose-1,6-bisphosphatase, chloroplastic from Spinacia oleracea

Seq: 415 a.a.

Struc: 333 a.a.*

* PDB and UniProt seqs differ at 3 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.3.1.3.11 - fructose-bisphosphatase.
• Pathway: Pentose Phosphate Pathway (later stages)
• Reaction: beta-D-fructose 1,6-bisphosphate + H2O = beta-D-fructose 6-phosphate + phosphate

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

DOI no: 10.1021/bi00013a019

Biochemistry 34:4299-4306 (1995)

PubMed id: 7703243

Crystal structure of spinach chloroplast fructose-1,6-bisphosphatase at 2.8 A resolution.

V.Villeret, S.Huang, Y.Zhang, Y.Xue, W.N.Lipscomb.

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.