Beta-ketoacyl-ACP synthase

From Wikipedia, the free encyclopedia
Jump to: navigation, search
3-oxoacyl-ACP synthase, mitochondrial
Symbol OXSM
Entrez 54995
HUGO 26063
OMIM 610324
RefSeq NM_017897
UniProt Q9NWU1
Other data
EC number
Locus Chr. 3 p24.2
Beta-ketoacyl synthase, N-terminal domain
PDB 1oxh EBI.jpg
the crystal structure of beta-ketoacyl-[acyl carrier protein] synthase ii from streptococcus pneumoniae, triclinic form
Symbol ketoacyl-synt
Pfam PF00109
Pfam clan CL0046
InterPro IPR014030
SCOP 1kas
Beta-ketoacyl synthase, C-terminal domain
PDB 2ix4 EBI.jpg
arabidopsis thaliana mitochondrial beta-ketoacyl acp synthase hexanoic acid complex
Symbol Ketoacyl-synt_C
Pfam PF02801
Pfam clan CL0046
InterPro IPR014031
SCOP 1kas

In molecular biology, Beta-ketoacyl-ACP synthase EC, is an enzyme involved in fatty acid synthesis. It results in the formation of acetoacetyl ACP. FattyAcid-MB-Condensation.png

It is the enzyme that catalyses the condensation of malonyl-ACP with the growing fatty acid chain.[1] It is found as a component of a number of enzymatic systems, including fatty acid synthetase (FAS), which catalyses the formation of long-chain fatty acids from acetyl-CoA, malonyl-CoA and NADPH; the multi-functional 6-methysalicylic acid synthase (MSAS) from Penicillium patulum,[2] which is involved in the biosynthesis of a polyketide antibiotic; polyketide antibiotic synthase enzyme systems; Emericella nidulans multifunctional protein Wa, which is involved in the biosynthesis of conidial green pigment; Rhizobium nodulation protein nodE, which probably acts as a beta-ketoacyl synthase in the synthesis of the nodulation Nod factor fatty acyl chain; and yeast mitochondrial protein CEM1. The condensation reaction is a two-step process: first the acyl component of an activated acyl primer is transferred to a cysteine residue of the enzyme and is then condensed with an activated malonyl donor with the concomitant release of carbon dioxide.

Beta-ketoacyl synthase contains two protein domains. The active site is located between the N- and C-terminal domains. The N-terminal domain contains most of the structures involved in dimer formation and also the active site cysteine. Residues from both domains contribute to substrate binding and catalysis[3]

See also[edit]

External links[edit]


  1. ^ Kauppinen S, Siggaard-Andersen M, von Wettstein-Knowles P (1988). "beta-Ketoacyl-ACP synthase I of Escherichia coli: nucleotide sequence of the fabB gene and identification of the cerulenin binding residue". Carlsberg Res. Commun. 53 (6): 357–70. doi:10.1007/bf02983311. PMID 3076376. 
  2. ^ Beck J, Ripka S, Siegner A, Schiltz E, Schweizer E (September 1990). "The multifunctional 6-methylsalicylic acid synthase gene of Penicillium patulum. Its gene structure relative to that of other polyketide synthases". Eur. J. Biochem. 192 (2): 487–98. doi:10.1111/j.1432-1033.1990.tb19252.x. PMID 2209605. 
  3. ^ Huang W, Jia J, Edwards P, Dehesh K, Schneider G, Lindqvist Y (1998). "Crystal structure of beta-ketoacyl-acyl carrier protein synthase II from E.coli reveals the molecular architecture of condensing enzymes.". EMBO J 17 (5): 1183–91. doi:10.1093/emboj/17.5.1183. PMC 1170466. PMID 9482715. 

This article incorporates text from the public domain Pfam and InterPro IPR014030

This article incorporates text from the public domain Pfam and InterPro IPR014031