| Phosphoketolase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 4.1.2.9 | ||||||||
| CAS no. | 9031-75-8 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
The enzyme phosphoketolase(EC 4.1.2.9) catalyzes the chemical reactions
- D-xylulose 5-phosphate + phosphate acetyl phosphate + D-glyceraldehyde 3-phosphate + H2O (EC 4.1.2.9) [1]
- D-fructose 6-phosphate + phosphate acetyl phosphate + D-erythrose 4-phosphate + H2O (EC 4.1.2.22)[2]
- D-sedoheptulose 7-phosphate + phosphate acetyl phosphate + D-ribose 5-phosphate + H2O[3]
Phosphoketolase is considered a promiscuous enzyme because it was demonstrated to use 3 different sugar phosphates as substrates. In a recent genetic study, more than 150 putative phosphoketolase genes exhibiting varying catalytic properties were found in 650 analyzed bacterial genomes.[4]
This enzyme belongs to the family of lyases, specifically the aldehyde-lyases, which cleave carbon-carbon bonds. It participates in 3 metabolic pathways: pentose phosphate pathway, methane metabolism, and carbon fixation. It employs one cofactor, thiamin diphosphate. Phosphoketolase was previously used for biotechnological purposes[5][6][7] as it enables the construction of synthetic pathways that allow complete carbon conservation without the generation of reducing power.[8]
