IUBMB Enzyme Nomenclature


Accepted name: carboxymethylproline synthase

Reaction: malonyl-CoA + (S)-1-pyrroline-5-carboxylate + H2O = CoA + (2S,5S)-5-carboxymethylproline + CO2

Other name(s): CarB (ambiguous)

Systematic name: malonyl-CoA:(S)-1-pyrroline-5-carboxylate malonyltransferase (cyclizing)

Comments: The enzyme is involved in the biosynthesis of the carbapenem β-lactam antibiotic (5R)-carbapen-2-em-3-carboxylate in the bacterium Pectobacterium carotovorum.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, PDB, CAS registry number:


1. Sleeman, M.C. and Schofield, C.J. Carboxymethylproline synthase (CarB), an unusual carbon-carbon bond-forming enzyme of the crotonase superfamily involved in carbapenem biosynthesis. J. Biol. Chem. 279 (2004) 6730-6736. [PMID: 14625287]

2. Gerratana, B., Arnett, S.O., Stapon, A. and Townsend, C.A. Carboxymethylproline synthase from Pectobacterium carotorova: a multifaceted member of the crotonase superfamily. Biochemistry 43 (2004) 15936-15945. [PMID: 15595850]

3. Sorensen, J.L., Sleeman, M.C. and Schofield, C.J. Synthesis of deuterium labelled L- and D-glutamate semialdehydes and their evaluation as substrates for carboxymethylproline synthase (CarB)—implications for carbapenem biosynthesis. Chem. Commun. (Camb.) (2005) 1155-1157. [PMID: 15726176]

4. Sleeman, M.C., Sorensen, J.L., Batchelar, E.T., McDonough, M.A. and Schofield, C.J. Structural and mechanistic studies on carboxymethylproline synthase (CarB), a unique member of the crotonase superfamily catalyzing the first step in carbapenem biosynthesis. J. Biol. Chem. 280 (2005) 34956-34965. [PMID: 16096274]

5. Batchelar, E.T., Hamed, R.B., Ducho, C., Claridge, T.D., Edelmann, M.J., Kessler, B. and Schofield, C.J. Thioester hydrolysis and C-C bond formation by carboxymethylproline synthase from the crotonase superfamily. Angew. Chem. Int. Ed. Engl. 47 (2008) 9322-9325. [PMID: 18972478]

6. Hamed, R.B., Gomez-Castellanos, J.R., Thalhammer, A., Harding, D., Ducho, C., Claridge, T.D. and Schofield, C.J. Stereoselective C-C bond formation catalysed by engineered carboxymethylproline synthases. Nat. Chem. 3 (2011) 365-371. [PMID: 21505494]

[EC created 2013]

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