PDBsum entry 2zci

Signaling protein, lyase

PDB id: 2zci

Contents

Protein chains

586 a.a. *

Waters ×326

* Residue conservation analysis

PDB id:

2zci

Name:

Signaling protein, lyase

Title:

Structure of a gtp-dependent bacterial pep-carboxykinase from corynebacterium glutamicum

Structure:

Phosphoenolpyruvate carboxykinase [gtp]. Chain: a, b, c, d. Synonym: pep carboxykinase. Phosphoenolpyruvate carboxylase. Pepck. Ec: 4.1.1.32

Source:

Corynebacterium glutamicum. Organism_taxid: 1718. Other_details: gene pckg, pck

Resolution:

2.30Å R-factor: 0.192 R-free: 0.279

Authors:

S.Aich,L.Prasad,L.T.J.Delbaere

Key ref:

S.Aich et al. (2008). Structure of a GTP-dependent bacterial PEP-carboxykinase from Corynebacterium glutamicum. Int J Biochem Cell Biol, 40, 1597-1603. PubMed id: 18234538 DOI: 10.1016/j.biocel.2007.12.002

Date:

09-Nov-07 Release date: 15-Apr-08

Protein chains

Q9AEM1  (PCKG_CORGL) -  Phosphoenolpyruvate carboxykinase [GTP] from Corynebacterium glutamicum (strain ATCC 13032 / DSM 20300 / BCRC 11384 / JCM 1318 / LMG 3730 / NCIMB 10025)

Seq: 610 a.a.

Struc: 586 a.a.

Enzyme reactions

• Enzyme class: E.C.4.1.1.32 - phosphoenolpyruvate carboxykinase (GTP).
• Reaction: oxaloacetate + GTP = phosphoenolpyruvate + GDP + CO2

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

reference

DOI no: 10.1016/j.biocel.2007.12.002

Int J Biochem Cell Biol 40:1597-1603 (2008)

PubMed id: 18234538

Structure of a GTP-dependent bacterial PEP-carboxykinase from Corynebacterium glutamicum.

S.Aich, L.Prasad, L.T.Delbaere.

ABSTRACT

GTP-dependent phosphoenolpyruvate carboxykinase (PCK) is the key enzyme that controls the blood glucose level during fasting in higher animals. Here we report the first substrate-free structure of a GTP-dependent phosphoenolpyruvate (PEP) carboxykinase from a bacterium, Corynebacterium glutamicum (CgPCK). The protein crystallizes in space group P2(1) with four molecules per asymmetric unit. The 2.3A resolution structure was solved by molecular replacement using the human cytosolic PCK (hcPCK) structure (PDB ID: 1KHF) as the starting model. The four molecules in the asymmetric unit pack as two dimers, and is an artifact of crystal packing. However, the P-loop and the guanine binding loop of the substrate-free CgPCK structure have different conformations from the other published GTP-specific PCK structures, which all have bound substrates and/or metal ions. It appears that a change in the P-loop and guanine binding loop conformation is necessary for substrate binding in GTP-specific PCKs, as opposed to overall domain movement in ATP-specific PCKs.