Reaction: malonyl-CoA + an [acyl-carrier protein] = CoA + a malonyl-[acyl-carrier protein]
Other name(s): [acyl carrier protein]malonyltransferase; FabD; malonyl coenzyme A-acyl carrier protein transacylase; malonyl transacylase; malonyl transferase; malonyl-CoA-acyl carrier protein transacylase; malonyl-CoA:[acyl-carrier-protein] S-malonyltransferase; malonyl-CoA:ACP transacylase; malonyl-CoA:ACP-SH transacylase; malonyl-CoA:AcpM transacylase; malonyl-CoA:acyl carrier protein transacylase; malonyl-CoA:acyl-carrier-protein transacylase; malonyl-CoA/dephospho-CoA acyltransferase; MAT; MCAT; MdcH
Systematic name: malonyl-CoA:[acyl-carrier protein] S-malonyltransferase
Comments: This enzyme, along with EC 2.3.1.38, [acyl-carrier-protein] S-acetyltransferase, is essential for the initiation of fatty-acid biosynthesis in bacteria. This enzyme also provides the malonyl groups for polyketide biosynthesis [7]. 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, holo-[acyl-carrier-protein] synthase) is the preferred substrate [5]. This enzyme also forms part of the multienzyme complexes EC 4.1.1.88 (biotin-independent malonate decarboxylase) and EC 7.2.4.4, biotin-dependent malonate decarboxylase. Malonylation of ACP is immediately followed by decarboxylation within the malonate-decarboxylase complex to yield acetyl-ACP, the catalytically active species of the decarboxylase [12]. In the enzyme from Klebsiella pneumoniae, methylmalonyl-CoA can also act as a substrate but acetyl-CoA cannot [10] whereas the enzyme from Pseudomonas putida can use both as substrates [11]. 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.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 37257-17-3
References:
1. Alberts, A.W., Majerus, P.W. and Vagelos, P.R. Acetyl-CoA acyl carrier protein transacylase. Methods Enzymol. 14 (1969) 50-53.
2. Prescott, D.J. and Vagelos, P.R. Acyl carrier protein. Adv. Enzymol. Relat. Areas Mol. Biol. 36 (1972) 269-311. [PMID: 4561013]
3. Williamson, I.P. and Wakil, S.J. Studies on the mechanism of fatty acid synthesis. XVII. Preparation and general properties of acetyl coenzyme A and malonyl coenzyme A-acyl carrier protein transacylases. J. Biol. Chem. 241 (1966) 2326-2332. [PMID: 5330116]
4. Joshi, V.C. and Wakil, S.J. Studies on the mechanism of fatty acid synthesis. XXVI. Purification and properties of malonyl-coenzyme A--acyl carrier protein transacylase of Escherichia coli. Arch. Biochem. Biophys. 143 (1971) 493-505. [PMID: 4934182]
5. Kremer, L., Nampoothiri, K.M., Lesjean, S., Dover, L.G., Graham, S., Betts, J., Brennan, P.J., Minnikin, D.E., Locht, C. and Besra, G.S. Biochemical characterization of acyl carrier protein (AcpM) and malonyl-CoA:AcpM transacylase (mtFabD), two major components of Mycobacterium tuberculosis fatty acid synthase II. J. Biol. Chem. 276 (2001) 27967-27974. [PMID: 11373295]
6. Keatinge-Clay, A.T., Shelat, A.A., Savage, D.F., Tsai, S.C., Miercke, L.J., O'Connell, J.D., 3rd, Khosla, C. and Stroud, R.M. Catalysis, specificity, and ACP docking site of Streptomyces coelicolor malonyl-CoA:ACP transacylase. Structure 11 (2003) 147-154. [PMID: 12575934]
7. Szafranska, A.E., Hitchman, T.S., Cox, R.J., Crosby, J. and Simpson, T.J. Kinetic and mechanistic analysis of the malonyl CoA:ACP transacylase from Streptomyces coelicolor indicates a single catalytically competent serine nucleophile at the active site. Biochemistry 41 (2002) 1421-1427. [PMID: 11814333]
8. Hoenke, S., Schmid, M. and Dimroth, P. Sequence of a gene cluster from Klebsiella pneumoniae encoding malonate decarboxylase and expression of the enzyme in Escherichia coli. Eur. J. Biochem. 246 (1997) 530-538. [PMID: 9208947]
9. Koo, J.H. and Kim, Y.S. Functional evaluation of the genes involved in malonate decarboxylation by Acinetobacter calcoaceticus. Eur. J. Biochem. 266 (1999) 683-690. [PMID: 10561613]
10. Hoenke, S. and Dimroth, P. Formation of catalytically active acetyl-S-malonate decarboxylase requires malonyl-coenzyme A:acyl carrier protein transacylase as auxiliary enzyme. Eur. J. Biochem. 259 (1999) 181-187. [PMID: 9914491]
11. Chohnan, S., Fujio, T., Takaki, T., Yonekura, M., Nishihara, H. and Takamura, Y. Malonate decarboxylase of Pseudomonas putida is composed of five subunits. FEMS Microbiol. Lett. 169 (1998) 37-43. [PMID: 9851033]
12. Dimroth, P. and Hilbi, H. Enzymic and genetic basis for bacterial growth on malonate. Mol. Microbiol. 25 (1997) 3-10. [PMID: 11902724]