Conserved Site

Xylulose 5-phosphate/Fructose 6-phosphate phosphoketolase, conserved site (IPR019790)

Short name: Xul5P/Fru6P_PKetolase_CS


Phosphoketolases (PK) are key enzymes of the pentose phosphate pathway of heterofermentative and facultative homofermentative lactic acid bacteria and of the D-fructose 6-phosphate shunt of bifidobacteria. PK activity has been sporadically reported in other microorganisms including eukaryotic yeasts. Xylulose-5-phosphate/fructose-6-phosphate phosphoketolase is a thiamine diphosphate (ThdP)-dependent enzyme found in bacteria such as Bifidobacterium sp [PMID: 11292814, PMID: 15899413]. This enzyme has dual-specificity with the following catalytic activities:

  • EC: xylose 5-P + Pi = acetyl-P + glyeraldehyde-3-P
  • EC: fructose-6-P + Pi = acetyl-P + erythrose-4-P

Phosphoketolases are distantly related to transketolases, e.g. IPR005475.

A multiple alignment of PK sequences shows several highly conserved regions. The function of the conserved site represented by the signature in this entry is unknown.

GO terms

Biological Process

GO:0005975 carbohydrate metabolic process

Molecular Function

GO:0016832 aldehyde-lyase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns