Any feedback?
Please rate this page
(ecexplorer.php)
(0/150)

BRENDA support

EC Explorer

EC 2.3.1.304 Details
EC number
2.3.1.304
Accepted name
poly[(R)-3-hydroxyalkanoate] polymerase
Reaction
(3R)-3-hydroxyacyl-CoA + poly[(R)-3-hydroxyalkanoate]n = CoA + poly[(R)-3-hydroxyalkanoate]n+1
Other name(s)
PHA synthase, phaC (gene name), PhaE
Systematic name
poly(R)-3-hydroxyalkanoate (3R)-3-hydroxyacyltransferase
Comment
This is the key enzyme in the biosynthesis of polyhydroxyalkanoates (PHA), linear polyesters produced by bacteria as a means of carbon and energy storage [6]. The enzyme catalyses the stereoselective, covalent linkage of (3R)-3-hydroxyacyl-CoA thioesters in a transesterification reaction with concomitant release of coenzyme A. The growing polymer is attached to a conserved active site L-cysteine residue. Three types of PHA synthases have been proposed based on their substrate specificity and enzyme structure. Type I and type III synthases preferentially polymerize short chain hydroxyalkanoate monomers containing 3-5 carbon atoms [1,2]. The difference between these two types is that type I synthases are composed of only a single subunit (PhaC), whereas type III synthases are composed of two different subunits, PhaC and PhaE [3,5]. Type II synthases are also composed of a single subunit (PhaC), but preferentially polymerize monomers containing more than 5 carbon atoms [4].
History
created 2021
EC Tree
2.3.1.55 created 1976, deleted 1999
2.3.1.120 created 1990, deleted 1992
2.3.1.124 created 1990, deleted 1992