PDBsum entry 1c4t

Transferase

PDB id: 1c4t

Contents

Protein chains

226 a.a. *

Ligands

SO4 ×6

Waters ×28

* Residue conservation analysis

PDB id:

1c4t

Name:

Transferase

Title:

Catalytic domain from trimeric dihydrolipoamide succinyltransferase

Structure:

Protein (dihydrolipoamide succinyltransferase). Chain: a, b, c. Fragment: catalytic domain, residues 172 - 404. Synonym: e2o. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 469008. Strain: bl21(de3). Cellular_location: mitochondria. Gene: sucb. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Biol. unit:

Hexamer (from PQS)

Resolution:

3.00Å R-factor: 0.257 R-free: 0.286

Authors:

J.E.Knapp,D.Carroll,J.E.Lawson,S.R.Ernst,L.J.Reed,M.L.Hackert

Key ref:

J.E.Knapp et al. (2000). Expression, purification, and structural analysis of the trimeric form of the catalytic domain of the Escherichia coli dihydrolipoamide succinyltransferase. Protein Sci, 9, 37-48. PubMed id: 10739245 DOI: 10.1110/ps.9.1.37

Date:

22-Sep-99 Release date: 18-Feb-00

Protein chains

P0AFG6  (ODO2_ECOLI) -  Dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex from Escherichia coli (strain K12)

Seq: 405 a.a.

Struc: 226 a.a.

Enzyme reactions

• Enzyme class: E.C.2.3.1.61 - dihydrolipoyllysine-residue succinyltransferase.
• Pathway: Citric acid cycle
• Reaction: N₆-[(R)-dihydrolipoyl]-L-lysyl-[protein] + succinyl-CoA = N₆-[(R)- S(8)-succinyldihydrolipoyl]-L-lysyl-[protein] + CoA

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

Added reference

DOI no: 10.1110/ps.9.1.37

Protein Sci 9:37-48 (2000)

PubMed id: 10739245

Expression, purification, and structural analysis of the trimeric form of the catalytic domain of the Escherichia coli dihydrolipoamide succinyltransferase.

J.E.Knapp, D.Carroll, J.E.Lawson, S.R.Ernst, L.J.Reed, M.L.Hackert.

ABSTRACT

The dihydrolipoamide succinyltransferase (E2o) component of the alpha-ketoglutarate dehydrogenase complex catalyzes the transfer of a succinyl group from the S-succinyldihydrolipoyl moiety to coenzyme A. E2o is normally a 24-mer, but is found as a trimer when E2o is expressed with a C-terminal [His]6 tag. The crystal structure of the trimeric form of the catalytic domain (CD) of the Escherichia coli E2o has been solved to 3.0 A resolution using the Molecular Replacement method. The refined model contains an intact trimer in the asymmetric unit and has an R-factor of 0.257 (Rfree = 0.286) for 18,699 reflections between 10.0 and 3.0 A resolution. The core of tE2oCD (residues 187-396) superimposes onto that of the cubic E2oCD with an RMS difference of 0.4 A for all main-chain atoms. The C-terminal end of tE2oCD (residues 397-404) rotates by an average of 37 degrees compared to cubic E2oCD, disrupting the normal twofold interface. Despite the alteration of quaternary structure, the active site of tE2oCD shows no significant differences from that of the cubic E2oCD, although several side chains in the active site are more ordered in the trimeric form of E2oCD. Analysis of the available sequence data suggests that the majority of E2 components have active sites that resemble that of E. coli E2oCD. The remaining E2 components can be divided into three groups based on active-site sequence similarity. Analysis of the surface properties of both crystal forms of E. coli E2oCD suggests key residues that may be involved in the protein-protein contacts that occur between the catalytic and lipoyl domains of E2o.