IUBMB Enzyme Nomenclature


Accepted name: holo-[acyl-carrier-protein] synthase

Reaction: CoA-[4'-phosphopantetheine] + an apo-[acyl-carrier protein] = adenosine 3',5'-bisphosphate + an [acyl-carrier protein]

Glossary: apo-[acyl-carrier protein] = a family of proteins or protein domains that contain a conserved serine residue, which are involved in acyl-group transfer.
[acyl-carrier protein] = holo-[acyl-carrier protein] = ACP = holo-ACP = the active form of apo-[acyl-carrier protein], in which the hydroxyl group of the conserved serine is substituted by a 4'-phosphopantetheine group, resulting in a sulfydryl group at which the acyl group to be transferred may then be substituted.

Other name(s): acyl carrier protein holoprotein (holo-ACP) synthetase; holo-ACP synthetase; coenzyme A:fatty acid synthetase apoenzyme 4'-phosphopantetheine transferase; holosynthase; acyl carrier protein synthetase; holo-ACP synthase; PPTase; AcpS; ACPS; acyl carrier protein synthase; P-pant transferase; CoA:apo-[acyl-carrier-protein] pantetheinephosphotransferase; CoA-[4'-phosphopantetheine]:apo-[acyl-carrier-protein] 4'-pantetheinephosphotransferase

Systematic name: CoA-[4'-phosphopantetheine]:apo-[acyl-carrier protein] 4'-pantetheinephosphotransferase

Comments: Requires Mg2+. All polyketide synthases, fatty-acid synthases and non-ribosomal peptide synthases require post-translational modification of their constituent acyl-carrier-protein (ACP) domains to become catalytically active. The inactive apo-proteins are converted into their active holo-forms by transfer of the 4'-phosphopantetheinyl moiety of CoA to the sidechain hydroxy group of a conserved serine residue in each ACP domain [3]. The enzyme from human can activate both the ACP domain of the human cytosolic multifunctional fatty-acid synthase system (EC and that associated with human mitochondria as well as peptidyl-carrier and acyl-carrier-proteins from prokaryotes [6]. Removal of the 4-phosphopantetheinyl moiety from holo-ACP is carried out by EC, [acyl-carrier-protein] phosphodiesterase.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 37278-30-1


1. Elovson, J. and Vagelos, P.R. Acyl carrier protein. X. Acyl carrier protein synthetase. J. Biol. Chem. 243 (1968) 3603-3611. [PMID: 4872726]

2. Prescott, D.J. and Vagelos, P.R. Acyl carrier protein. Adv. Enzymol. Relat. Areas Mol. Biol. 36 (1972) 269-311. [PMID: 4561013]

3. Lambalot, R.H., Gehring, A.M., Flugel, R.S., Zuber, P., LaCelle, M., Marahiel, M.A., Reid, R., Khosla, C. and Walsh, C.T. A new enzyme superfamily - the phosphopantetheinyl transferases. Chem. Biol. 3 (1996) 923-936. [PMID: 8939709]

4. Walsh, C.T., Gehring, A.M., Weinreb, P.H., Quadri, L.E.N. and Flugel, R.S. Post-translational modification of polyketide and nonribosomal peptide synthases. Curr. Opin. Chem. Biol. 1 (1997) 309-315. [PMID: 9667867]

5. Mootz, H.D., Finking, R. and Marahiel, M.A. 4'-Phosphopantetheine transfer in primary and secondary metabolism of Bacillus subtilis. J. Biol. Chem. 276 (2001) 37289-37298. [PMID: 11489886]

6. Joshi, A.K., Zhang, L., Rangan, V.S. and Smith, S. Cloning, expression, and characterization of a human 4'-phosphopantetheinyl transferase with broad substrate specificity. J. Biol. Chem. 278 (2003) 33142-33149. [PMID: 12815048]

[EC created 1972, modified 2006, modified 2022]

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