PDBsum entry: 1r9j

Transferase

PDB id: 1r9j

Contents

Protein chains

670 a.a. *

Ligands

TPP ×2

Metals

_CA ×2

Waters ×911

* Residue conservation analysis

PDB id:

1r9j

Name:

Transferase

Title:

Transketolase from leishmania mexicana

Structure:

Transketolase. Chain: a, b. Engineered: yes

Source:

Leishmania mexicana mexicana. Organism_taxid: 44270. Strain: mexicana. Expressed in: escherichia coli. Expression_system_taxid: 562

Biol. unit:

Dimer (from PQS)

Resolution:

2.22Å R-factor: 0.170 R-free: 0.213

Authors:

N.J.Veitch,D.A.Mauger,J.J.Cazzulo,Y.Lindqvist,M.P.Barrett

Key ref:

N.J.Veitch et al. (2004). Transketolase from Leishmania mexicana has a dual subcellular localization. Biochem J, 382, 759-767. PubMed id: 15149284 Ref: Full text

Date:

30-Oct-03 Release date: 09-Nov-04

Protein chains

Q8MPM3  (Q8MPM3_LEIME) -  Transketolase

Seq: 671 a.a.

Struc: 670 a.a.

Enzyme reactions

• Enzyme class: E.C.2.2.1.1 - Transketolase.
• Reaction: Sedoheptulose 7-phosphate + D-glyceraldehyde 3-phosphate = D-ribose 5-phosphate + D-xylulose 5-phosphate
• Cofactor: Thiamine diphosphate

Thiamine diphosphate (Bound ligand (Het Group name = TPP) corresponds exactly)

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

 Gene Ontology (GO) functional annotation 

• Biological process: metabolic process (1 term)
• Biochemical function: catalytic activity (3 terms)

reference

Full text	Biochem J 382:759-767 (2004)
PubMed id: 15149284

Transketolase from Leishmania mexicana has a dual subcellular localization.

N.J.Veitch, D.A.Maugeri, J.J.Cazzulo, Y.Lindqvist, M.P.Barrett.

ABSTRACT

Transketolase has been characterized in Leishmania mexicana. A gene encoding this enzyme was identified and cloned. The gene was expressed in Escherichia coli and the protein was purified and characterized. An apparent K(m) of 2.75 mM for ribose 5-phosphate was determined. X-ray crystallography was used to determine the three-dimensional structure of the enzyme to a resolution of 2.2 A (1 A identical with 0.1 nm). The C-terminus of the protein contains a type-1 peroxisome-targeting signal, suggestive of a possible glycosomal subcellular localization. Subcellular localization experiments performed with promastigote forms of the parasite revealed that the protein was predominantly cytosolic, although a significant component of the total activity was associated with the glycosomes. Transketolase is thus the first enzyme of the nonoxidative branch of the pentose phosphate pathway whose presence has been demonstrated in a peroxisome-like organelle.