Synonyms: phosphopantotheine, pantetheine 4'-phosphate, phosphopantetheine
4'-phosphopantetheine is an essential prosthetic group of several acyl carrier proteins involved in pathways of primary and secondary metabolism. These include acyl carrier proteins (ACPs) of fatty acid synthases (FASs), ACPs of polyketide synthases (PKSs) and peptidyl carrier proteins (PCPs), and aryl carrier proteins of non-ribosomal peptide synthetases.
The free thiol moiety of 4'-phosphopantetheine serves to covalently bind the acyl reaction intermediates as thioesters during the multistep assembly of the monomeric precursors, typically acetyl, malonyl, and aminoacyl groups [Mootz01].
The 4'-phosphopantetheine moiety is derived from coenzyme A (CoA) and posttranslationally transferred onto an invariant serine side chain, as described in EC 188.8.131.52:
This Mg2+-dependent conversion of the apoproteins to the holoproteins is catalyzed by the 4'-phosphopantetheine transferases. Organisms often have several such enzymes; for example, Escherichia coli have three enzyes, encoded by acpS, entD and acpT.
Chemical Formula: C11H21N2O7PS
Molecular Weight: 356.33 Daltons
Monoisotopic Molecular Weight: 358.0963583034 Daltons
Standard Gibbs Free Energy of Change Formation (ΔfG'° in kcal/mol): -133.19473 [Latendresse13]
Reactions known to consume the compound:
Reactions known to produce the compound:
In Reactions of unknown directionality:
This compound has been characterized as a cofactor or prosthetic group of the following enzymes: L-seryl-AMP synthase , 6-deoxyerythronolide B synthase , acyl-CoA:malonyl-CoA C-acyltransferase , gramicidin S synthase , D-phenylalanyl-L-prolyl-L-valyl-L-ornithyl-L-leucyl-[NRPS-pcp] synthetase , D-phenylalanyl-[NRPS-pcp] synthetase , 3-amino-5,7-dihydroxy-6-methyl-8-[(2E,13E,15E)-5,7,9,11-tetrahydroxy-2,4,6,8,10,12,16-heptamethyl-17-oxooctadeca-2,13,15-trienoyl]-1,4,5,6-tetrahydronaphthalene-1,4-dione-[PKS-acp] synthase , 8-(3-amino-5-hydroxyphenyl)-8-hydroxy-3,7-dimethyloctane-2,4,6-trione -[PKS-acp] synthase , 1-(3-amino-5-hydroxyphenyl)ethan-1-one -[PKS-acp] synthase , acyl-CoA:malonyl-CoA C-acyltransferase , δ-(L-α-aminoadipyl)-L-cysteinyl-D-valine synthetase
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