PDBsum entry: 1fj6

Hydrolase

PDB id: 1fj6

Contents

Protein chain

328 a.a. *

Ligands

F6P

PO4 ×2

Metals

_ZN ×3

Waters ×84

* Residue conservation analysis

PDB id:

1fj6

Name:

Hydrolase

Title:

Fructose-1,6-bisphosphatase (mutant y57w) product/zn complex

Structure:

Fructose-1,6-bisphosphatase. Chain: a. Synonym: d-fructose-1,6-biphosphate 1-phosphohydrolase, fbp engineered: yes. Mutation: yes

Source:

Sus scrofa. Pig. Organism_taxid: 9823. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Tetramer (from PDB file)

Resolution:

2.50Å R-factor: 0.203 R-free: 0.272

Authors:

C.V.Iancu,J.Y.Choe,R.B.Honzatko

Key ref:

S.W.Nelson et al. (2000). Tryptophan fluorescence reveals the conformational state of a dynamic loop in recombinant porcine fructose-1,6-bisphosphatase. Biochemistry, 39, 11100-11106. PubMed id: 10998248 DOI: 10.1021/bi000609c

Date:

07-Aug-00 Release date: 18-Oct-00

Protein chain

P00636  (F16P1_PIG) -  Fructose-1,6-bisphosphatase 1

Seq: 338 a.a.

Struc: 328 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

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

D-fructose 1,6-bisphosphate + H(2)O = D-fructose 6-phosphate (Bound ligand (Het Group name = F6P) corresponds exactly) + phosphate (Bound ligand (Het Group name = PO4) corresponds exactly)

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

 Gene Ontology (GO) functional annotation 

• Biological process: metabolic process (3 terms)
• Biochemical function: catalytic activity (5 terms)

reference

DOI no: 10.1021/bi000609c

Biochemistry 39:11100-11106 (2000)

PubMed id: 10998248

Tryptophan fluorescence reveals the conformational state of a dynamic loop in recombinant porcine fructose-1,6-bisphosphatase.

S.W.Nelson, C.V.Iancu, J.Y.Choe, R.B.Honzatko, H.J.Fromm.

ABSTRACT

Wild-type porcine fructose-1,6-bisphosphatase (FBPase) has no tryptophan residues. Hence, the mutation of Try57 to tryptophan places a unique fluorescent probe in the structural element (loop 52-72) putatively responsible for allosteric regulation of catalysis. On the basis of steady-state kinetics, circular dichroism spectroscopy, and X-ray crystallography, the mutation has little effect on the functional and structural properties of the enzyme. Fluorescence intensity from the Trp57 mutant is maximal in the presence of divalent cations, fructose 6-phosphate and orthophosphate, which together stabilize an R-state conformation in which loop 52-72 is engaged with the active site. The level of fluorescence emission decreases monotonically with increasing levels of AMP, an allosteric inhibitor, which promotes the T-state, disengaged-loop conformation. The titration of various metal-product complexes of the Trp57 mutant with fructose 2,6-bisphosphate (F26P(2)) causes similar decreases in fluorescence, suggesting that F26P(2) and AMP individually induce similar conformational states in FBPase. Fluorescence spectra, however, are sensitive to the type of divalent cation (Zn(2+), Mn(2+), or Mg(2+)) and suggest conformations in addition to the R-state, loop-engaged and T-state, loop-disengaged forms of FBPase. The work presented here demonstrates the utility of fluorescence spectroscopy in probing the conformational dynamics of FBPase.