Biology:Holo-(acyl-carrier-protein) synthase

From HandWiki
phosphopantetheinyltransferase
5xuk.jpg
holo-[acyl-carrier-protein] synthase trimer, Helicobacter pylori
Identifiers
EC number2.7.8.7
CAS number37278-30-1
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO
ACPS
PDB 1qr0 EBI.jpg
crystal structure of the 4'-phosphopantetheinyl transferase sfp-coenzyme a complex
Identifiers
SymbolACPS
PfamPF01648
InterProIPR008278
SCOP21qr0 / SCOPe / SUPFAM

In enzymology and molecular biology, a holo-[acyl-carrier-protein] synthase (ACPS, EC 2.7.8.7) is an enzyme that catalyzes the chemical reaction:

CoA-[4'-phosphopantetheine] + apo-acyl carrier protein [math]\displaystyle{ \rightleftharpoons }[/math] adenosine 3',5'-bisphosphate + holo-acyl carrier protein

This enzyme belongs to the family of transferases, specifically those transferring non-standard substituted phosphate groups. It is also known as 4'-phosphopantetheinyl transferase after the group it transfers.

Function

All ACPS enzymes known so far are evolutionally related to each other in a single superfamily of proteins. It transfers a 4'-phosphopantetheine (4'-PP) moiety from coenzyme A (CoA) to an invariant serine in an acyl carrier protein (ACP), a small protein responsible for acyl group activation in fatty acid biosynthesis. This post-translational modification renders holo-ACP capable of acyl group activation via thioesterification of the cysteamine thiol of 4'-PP.[1] This superfamily consists of two subtypes: the trimeric ACPS type such as E. coli ACPS and the monomeric Sfp (PCP-synthesizing) type such as B. subtilis SFP. Structures from both families are now known. The active site accommodates a magnesium ion. The most highly conserved regions of the protein are involved in binding the magnesium ion.[2][3]

Nomenclature

The systematic name of this enzyme class is CoA-[4'-phosphopantetheine]:apo-[acyl-carrier-protein] 4'-pantetheinephosphotransferase. Other names in common use, disregarding the synthetase/synthase spelling difference, include acyl carrier protein holoprotein synthetase, holo-ACP synthetase, coenzyme A:fatty acid synthetase apoenzyme 4'-phosphopantetheine, acyl carrier protein synthetase (ACPS), PPTase, acyl carrier protein synthase, P-pant transferase, and CoA:apo-[acyl-carrier-protein] pantetheinephosphotransferase.

Structural studies

As of late 2007, 8 structures have been solved for this class of enzymes, with PDB accession codes 1F7L, 1F7T, 1F80, 1FTE, 1FTF, 1FTH, 2JBZ, and 2JCA.

References

  1. "Cloning, overproduction, and characterization of the Escherichia coli holo-acyl carrier protein synthase". The Journal of Biological Chemistry 270 (42): 24658–61. October 1995. doi:10.1074/jbc.270.42.24658. PMID 7559576. 
  2. "Crystal structure of the surfactin synthetase-activating enzyme sfp: a prototype of the 4'-phosphopantetheinyl transferase superfamily". The EMBO Journal 18 (23): 6823–31. December 1999. doi:10.1093/emboj/18.23.6823. PMID 10581256. 
  3. "Structure, High Affinity, and Negative Cooperativity of the Escherichia coli Holo-(Acyl Carrier Protein):Holo-(Acyl Carrier Protein) Synthase Complex.". Journal of Molecular Biology 429 (23): 3763–3775. 24 November 2017. doi:10.1016/j.jmb.2017.10.015. PMID 29054754. 

Further reading

This article incorporates text from the public domain Pfam and InterPro: IPR008278