Biology:Phytoene synthase

From HandWiki
Short description: Class of enzymes
15-cis-phytoene synthase
Identifiers
EC number2.5.1.32
CAS number50936-61-3
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum

Phytoene synthase (EC 2.5.1.32, prephytoene-diphosphate synthase, 15-cis-phytoene synthase, PSase, geranylgeranyl-diphosphate geranylgeranyltransferase) is a transferase enzyme involved in the biosynthesis of carotenoids. It catalyzes the conversion of geranylgeranyl pyrophosphate to phytoene.[1][2][3][4] This enzyme catalyses the following chemical reaction

2 geranylgeranyl diphosphate [math]\displaystyle{ \rightleftharpoons }[/math] 15-cis-phytoene + 2 diphosphate (overall reaction)
(1a) 2 geranylgeranyl diphosphate [math]\displaystyle{ \rightleftharpoons }[/math] diphosphate + prephytoene diphosphate
(1b) prephytoene diphosphate [math]\displaystyle{ \rightleftharpoons }[/math] 15-cis-phytoene + diphosphate

This enzyme requires Mn2+ for activity. It belongs to squalene/phytoene synthase family of proteins.

References

  1. Phytoene synthase
  2. "The stereochemistry of trans-phytoene synthesis. Some observations on lycopersene as a carotene precursor and a mechanism for the synthesis of cis- and trans-phytoene". Biochemistry 13 (7): 1538–42. March 1974. doi:10.1021/bi00704a033. PMID 4819767. 
  3. Chamovitz, Daniel; Misawa, Norihiko; Sandmann, Gerhard; Hirschberg, Joseph (27 January 1992). "Molecular cloning and expression in of a cyanobacterial gene coding for phytoene synthase, a carotenoid biosynthesis enzyme". FEBS Letters 296 (3): 305–310. doi:10.1016/0014-5793(92)80310-d. 
  4. "Expression of a tomato cDNA coding for phytoene synthase in Escherichia coli, phytoene formation in vivo and in vitro, and functional analysis of the various truncated gene products". Journal of Biochemistry 116 (5): 980–5. November 1994. PMID 7896759.