Phosphopantetheine, also known as 4'-phosphopantetheine, is a prosthetic group of several acyl carrier proteins including the acyl carrier proteins (ACP) of
fatty acid synthases, ACPs of
polyketide synthase
Polyketides are a class of natural products derived from a precursor molecule consisting of a chain of alternating ketone (or reduced forms of a ketone) and methylene groups: (-CO-CH2-). First studied in the early 20th century, discovery, biosynth ...
s, the peptidyl carrier proteins (PCP), as well as aryl carrier proteins (ArCP) of
nonribosomal peptide synthetases (NRPS). It is also present in
formyltetrahydrofolate dehydrogenase.
Subsequent to the expression of the ''apo''
acyl carrier protein
The acyl carrier protein (ACP) is a cofactor of both fatty acid and polyketide
Polyketides are a class of natural products derived from a precursor molecule consisting of a chain of alternating ketone (or reduced forms of a ketone) and methylene ...
, 4'-phosphopantetheine moiety is attached to a serine residue. The coupling involves formation of a
phosphodiester linkage. This coupling is mediated by
acyl carrier protein synthase (ACPS), a
4'-phosphopantetheinyl transferase.
Phosphopantetheine prosthetic group covalently links to the acyl group via a high energy thioester bond. The flexibility and length of the phosphopantetheine chain (approximately 2 nm) allows the covalently tethered intermediates to access spatially distinct enzyme-active sites. This accessibility increases the effective molarity of the intermediate and allows an assembly line-like process.
See also
*
Fatty acid synthase
*
Pantothenic acid
Pantothenic acid, also called vitamin B5 is a water-soluble B vitamin and therefore an essential nutrient. All animals require pantothenic acid in order to synthesize coenzyme A (CoA) – essential for fatty acid metabolism – as well as to, ...
References
Biomolecules
Metabolism
Thiols
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