CATH Classification

Domain Context

CATH Clusters

Superfamily Malonyl-CoA ACP transacylase, ACP-binding
Functional Family Fatty acid synthase, putative

Enzyme Information

1.1.1.100
3-oxoacyl-[acyl-carrier-protein] reductase.
based on mapping to UniProt P49327
(3R)-3-hydroxyacyl-[acyl-carrier-protein] + NADP(+) = 3-oxoacyl-[acyl- carrier-protein] + NADPH.
-!- Exhibits a marked preference for [acyl-carrier-protein] derivatives over CoA derivatives as substrates.
2.3.1.41
Beta-ketoacyl-[acyl-carrier-protein] synthase I.
based on mapping to UniProt P49327
Acyl-[acyl-carrier-protein] + malonyl-[acyl-carrier-protein] = 3-oxoacyl- [acyl-carrier-protein] + CO(2) + [acyl-carrier-protein].
-!- Responsible for the chain-elongation step of dissociated (type II) fatty-acid biosynthesis, i.e. the addition of two C atoms to the fatty-acid chain. -!- Escherichia coli mutants that lack this enzyme are deficient in unsaturated fatty acids. -!- Can use fatty acyl thioesters of ACP (C(2) to C(16)) as substrates, as well as fatty acyl thioesters of Co-A (C(4) to C(16)). -!- The substrate specificity is very similar to that of EC 2.3.1.179 with the exception that the latter enzyme is far more active with palmitoleoyl-ACP (C(16)-Delta(9)) as substrate, allowing the organism to regulate its fatty-acid composition with changes in temperature.
1.3.1.39
Enoyl-[acyl-carrier-protein] reductase (NADPH, Re-specific).
based on mapping to UniProt P49327
An acyl-[acyl-carrier protein] + NADP(+) = a trans-2,3-dehydroacyl-[acyl- carrier protein] + NADPH.
-!- This enzyme completes each cycle of fatty acid elongation by catalyzing the stereospecific reduction of the double bond at position 2 of a growing fatty acid chain, while linked to an acyl- carrier protein. -!- It is one of the activities of EC 2.3.1.85. -!- The mammalian enzyme is Re-specific with respect to NADP(+) (cf. EC 1.3.1.10 and and EC 1.3.1.104).
2.3.1.38
[Acyl-carrier-protein] S-acetyltransferase.
based on mapping to UniProt P49327
Acetyl-CoA + [acyl-carrier-protein] = CoA + acetyl-[acyl-carrier- protein].
-!- Essential, along with EC 2.3.1.39, for the initiation of fatty-acid biosynthesis in bacteria. -!- The substrate acetyl-CoA protects the enzyme against inhibition by N-ethylmaleimide or iodoacetamide. -!- This is one of the activities associated with EC 2.3.1.180.
2.3.1.85
Fatty-acid synthase.
based on mapping to UniProt P49327
Acetyl-CoA + n malonyl-CoA + 2n NADPH = a long-chain fatty acid + (n+1) CoA + n CO(2) + 2n NADP(+).
-!- The animal enzyme is a multifunctional protein catalyzing the reactions of EC 2.3.1.38, EC 2.3.1.39, EC 2.3.1.41, EC 1.1.1.100, EC 4.2.1.59, EC 1.3.1.39 and EC 3.1.2.14.
2.3.1.39
[Acyl-carrier-protein] S-malonyltransferase.
based on mapping to UniProt P49327
Malonyl-CoA + an [acyl-carrier-protein] = CoA + a malonyl-[acyl-carrier- protein].
-!- Essential, along with EC 2.3.1.38, for the initiation of fatty-acid biosynthesis in bacteria. -!- Also provides the malonyl groups for polyketide biosynthesis. -!- The product of the reaction, malonyl-ACP, is an elongation substrate in fatty-acid biosynthesis. -!- In Mycobacterium tuberculosis, holo-ACP (the product of EC 2.7.8.7) is the preferred substrate. -!- This enzyme also forms part of the multienzyme complexes EC 4.1.1.88 and EC 4.1.1.89. -!- Malonylation of ACP is immediately followed by decarboxylation within the malonate-decarboxylase complex to yield acetyl-ACP, the catalytically active species of the decarboxylase. -!- In the enzyme from Klebsiella pneumoniae, methylmalonyl-CoA can also act as a substrate but acetyl-CoA cannot whereas the enzyme from Pseudomonas putida can use both as substrates. -!- The ACP subunit found in fatty-acid biosynthesis contains a pantetheine-4'-phosphate prosthetic group; that from malonate decarboxylase also contains pantetheine-4'-phosphate but in the form of a 2'-(5-triphosphoribosyl)-3'-dephospho-CoA prosthetic group.
3.1.2.14
Oleoyl-[acyl-carrier-protein] hydrolase.
based on mapping to UniProt P49327
Oleoyl-[acyl-carrier-protein] + H(2)O = [acyl-carrier-protein] + oleate.
-!- Acts on [acyl-carrier-protein] thioesters of fatty acids from C(12) to C(18), but the derivative of oleic acid is hydrolyzed much more rapidly than any other compound tested.
4.2.1.59
3-hydroxyacyl-[acyl-carrier-protein] dehydratase.
based on mapping to UniProt P49327
A (3R)-3-hydroxyacyl-[acyl-carrier protein] = a trans-2-enoyl-[acyl- carrier protein] + H(2)O.
-!- This enzyme is responsible for the dehydration step of the dissociated (type II) fatty-acid biosynthesis system that occurs in plants and bacteria. -!- The enzyme uses fatty acyl thioesters of ACP in vivo. -!- Different forms of the enzyme may have preferences for substrates with different chain length. -!- For example, the activity of FabZ, the ubiquitous enzyme in bacteria, decreases with increasing chain length. -!- Gram-negative bacteria that produce unsaturated fatty acids, such as Escherichia coli, have another form (FabA) that prefers intermediate chain length, and also catalyzes EC 5.3.3.14. -!- Despite the differences both forms can catalyze all steps leading to the synthesis of palmitate (C16:0). -!- FabZ, but not FabA, can also accept unsaturated substrates. -!- Formerly EC 4.2.1.58, EC 4.2.1.60 and EC 4.2.1.61.

UniProtKB Entries (1)

P49327
FAS_HUMAN
Homo sapiens
Fatty acid synthase

PDB Structure

PDB 2JFD
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
Structural basis for different specificities of acyltransferases associated with the human cytosolic and mitochondrial fatty acid synthases.
Bunkoczi, G., Misquitta, S., Wu, X., Lee, W.H., Rojkova, A., Kochan, G., Kavanagh, K.L., Oppermann, U., Smith, S.
Chem. Biol.