PDBsum entry 2gps

Ligase

PDB id: 2gps

Contents

Protein chains

447 a.a. *

Waters ×67

* Residue conservation analysis

PDB id:

2gps

Name:

Ligase

Title:

Crystal structure of the biotin carboxylase subunit, e23r mutant, of acetyl-coa carboxylase from escherichia coli.

Structure:

Biotin carboxylase. Chain: a, b. Synonym: a subunit of acetyl-coa carboxylase, acc. Engineered: yes. Mutation: yes

Source:

Escherichia coli. Organism_taxid: 562. Gene: accc. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Dimer (from PQS)

Resolution:

2.80Å R-factor: 0.206 R-free: 0.260

Authors:

Y.Shen,C.Y.Chou,G.G.Chang,L.Tong

Key ref:

Y.Shen et al. (2006). Is dimerization required for the catalytic activity of bacterial biotin carboxylase? Mol Cell, 22, 807-818. PubMed id: 16793549 DOI: 10.1016/j.molcel.2006.04.026

Date:

18-Apr-06 Release date: 04-Jul-06

Protein chains

P24182  (ACCC_ECOLI) -  Biotin carboxylase from Escherichia coli (strain K12)

Seq: 449 a.a.

Struc: 447 a.a.*

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

Enzyme reactions

• Enzyme class 1: E.C.6.3.4.14 - biotin carboxylase.
• Reaction: N₆-biotinyl-L-lysyl-[protein] + hydrogencarbonate + ATP = N₆- carboxybiotinyl-L-lysyl-[protein] + ADP + phosphate + H⁺
• Enzyme class 2: E.C.6.4.1.2 - acetyl-CoA carboxylase.
• Reaction: hydrogencarbonate + acetyl-CoA + ATP = malonyl-CoA + ADP + phosphate + H⁺
• Cofactor: Biotin

Note, where more than one E.C. class is given (as above), each may correspond to a different protein domain or, in the case of polyprotein precursors, to a different mature protein.

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

reference

DOI no: 10.1016/j.molcel.2006.04.026

Mol Cell 22:807-818 (2006)

PubMed id: 16793549

Is dimerization required for the catalytic activity of bacterial biotin carboxylase?

Y.Shen, C.Y.Chou, G.G.Chang, L.Tong.

ABSTRACT

Acetyl-coenzyme A carboxylases (ACCs) have crucial roles in fatty acid metabolism. The biotin carboxylase (BC) subunit of Escherichia coli ACC is believed to be active only as a dimer, although the crystal structure shows that the active site of each monomer is 25 A from the dimer interface. We report here biochemical, biophysical, and structural characterizations of BC carrying single-site mutations in the dimer interface. Our studies demonstrate that two of the mutants, R19E and E23R, are monomeric in solution but have only a 3-fold loss in catalytic activity. The crystal structures of the E23R and F363A mutants show that they can still form the correct dimer at high concentrations. Our data suggest that dimerization is not an absolute requirement for the catalytic activity of the E. coli BC subunit, and we propose a new model for the molecular mechanism of action for BC in multisubunit and multidomain ACCs.

Selected figure(s)

Figure 2.
Figure 2. Sedimentation Velocity Analytical Ultracentrifugation Data for the BC Subunit

Figure 5.
Figure 5. A Model for the Mechanism of Action of BC

The above figures are reprinted by permission from Cell Press: Mol Cell (2006, 22, 807-818) copyright 2006.

Figures were selected by an automated process.