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Protein Domain : IPR020826

Name  Transketolase binding site Short Name  Transketolase_BS
Type  Binding_site Description  Transketolase (TK) catalyzes the reversible transfer of atwo-carbon ketol unit from xylulose 5-phosphate to an aldose receptor, such asribose 5-phosphate, to form sedoheptulose 7-phosphate and glyceraldehyde 3-phosphate. This enzyme, together with transaldolase, provides a link betweenthe glycolytic and pentose-phosphate pathways.TK requires thiamine pyrophosphate as a cofactor. In most sources where TK hasbeen purified, it is a homodimer of approximately 70 Kd subunits. TK sequencesfrom a variety of eukaryotic and prokaryotic sources [, ]show that theenzyme has been evolutionarily conserved.In the peroxisomes of methylotrophic yeast Pichia angusta(Yeast) (Hansenula polymorpha), there is ahighly related enzyme, dihydroxy-acetone synthase (DHAS) (alsoknown as formaldehyde transketolase), which exhibits a very unusualspecificity by including formaldehyde amongst its substrates.1-deoxyxylulose-5-phosphate synthase (DXP synthase) []is an enzyme so farfound in bacteria (gene dxs) and plants (gene CLA1) which catalyzes thethiamine pyrophosphoate-dependent acyloin condensation reaction between carbonatoms 2 and 3 of pyruvate and glyceraldehyde 3-phosphate to yield 1-deoxy-D-xylulose-5-phosphate (dxp), a precursor in the biosynthetic pathway toisoprenoids, thiamine (vitamin B1), and pyridoxol (vitamin B6). DXP synthaseis evolutionary related to TK. The N-terminal section, contains a histidine residue which appears to function inproton transfer during catalysis []. In the centralsection there are conserved acidic residues that are part of the active cleftand may participate in substrate-binding [].This family includes transketolase enzymes and also partially matches to 2-oxoisovalerate dehydrogenasebeta subunit . Both these enzymesutilise thiamine pyrophosphate as a cofactor, suggestingthere may be common aspects in their mechanism of catalysis.This entry is located in the central section and contains conserved acidic residues that are part of the active cleft and may participate in substrate-binding [].

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0 Child Features

0 Contains

1 Cross References

Source . Name

Subject . Primary Identifier
PS00802 PROSITE IPR020826

2 Data Sets

Name URL
TrEMBL data set
InterPro data set  

3 Found In

DB identifier Name Short Name Type
IPR005475 Transketolase-like, pyrimidine-binding domain Transketolase-like_Pyr-bd Domain
IPR005478 Transketolase, bacterial-like Transketolase_bac-like Family
IPR005477 Deoxyxylulose-5-phosphate synthase Dxylulose-5-P_synthase Family

0 GO Annotation

0 Ontology Annotations

0 Parent Features

18 Proteins

DB identifier Primary Accession
Organism . Name
FBpp0074898 Q9VVP4 Drosophila melanogaster
FBpp0081370 Q9VHN7 Drosophila melanogaster
FBpp0081372 Q7KSU6 Drosophila melanogaster
FBpp0281830 B5DWE4 Drosophila pseudoobscura
FBpp0171750 B4KCP2 Drosophila mojavensis
FBpp0224553 B4M501 Drosophila virilis
FBpp0267090 B4PJ30 Drosophila yakuba
FBpp0270902 B4PT84 Drosophila yakuba
A8WUX5_CAEBR A8WUX5 Caenorhabditis briggsae
H2WK87_CAEJA H2WK87 Caenorhabditis japonica
G0PJP7_CAEBE G0PJP7 Caenorhabditis brenneri
G0PIJ8_CAEBE G0PIJ8 Caenorhabditis brenneri
O17759_CAEEL O17759 Caenorhabditis elegans
Q95S19_DROME Q95S19 Drosophila melanogaster
Q8MZ62_DROME Q8MZ62 Drosophila melanogaster
E3NW37_CAERE E3NW37 Caenorhabditis remanei
E3MM61_CAERE E3MM61 Caenorhabditis remanei
E3NWD4_CAERE E3NWD4 Caenorhabditis remanei