PHA_synth_III_C

Family: PHA_synth_III_C

Block: X

Parent Family: Abhydrolase_6

Comment

(The family Pha_synthase was split in four families (PHA_synth_I, PHA_synth_II, PHA_synth_III, PhaC_cen_dom ) according to Interpro and Tigrpfam. PhaC_cen_dom groups enzyme with the central domain but not the class I,II,III domains)This entry represents the PhaC subunit of a heterodimeric form of polyhydroxyalkanoic acid (PHA) synthase. Excepting the PhaC of Bacillus megaterium (which needs PhaR is not an a/b hydrolase), all members require PhaE (IPR010123 PhaE is not an a/b hydrolase) subunit for activity and are designated class III. (PhaC of Bacillus associated to PhaR are designed Class IV PHA_synth_IV but are not separated here) . This enzyme builds ester polymers for carbon and energy storage that accumulate in inclusions, and both this enzyme and the depolymerase associate with the inclusions. Class III enzymes polymerise short-chain-length hydroxyalkanoates. Poly-beta-hydroxybutyrate polymerase (PhaC) N-terminus. This entry represents the central domain of the bacterial poly-beta-hydroxybutyrate polymerase (PhaC). Polyhydroxyalkanoic acids (PHAs) are carbon and energy reserve polymers produced in some bacteria when carbon sources are plentiful and another nutrient, such as nitrogen, phosphate, oxygen, or sulphur, becomes limiting. PHAs composed of monomeric units ranging from 3 to 14 carbons exist in nature. When the carbon source is exhausted, PHA is utilised by the bacterium. PhaC links D-(-)-3-hydroxybutyrl-CoA to an existing PHA molecule by the formation of an ester bond PHA_synth_I TIGR01838 PHA_synth_II TIGR01839. The nucleophilic residue of the catalytic triad is a cysteine (with exceptions)