IUBMB Enzyme Nomenclature


Accepted name: isopenicillin-N synthase

Reaction: N-[(5S)-5-amino-5-carboxypentanoyl]-L-cysteinyl-D-valine + O2 = isopenicillin N + 2 H2O

For diagram click here and possible mechanism click here.

Other name(s): isopenicillin N synthetase

Systematic name: N-[(5S)-5-amino-5-carboxypentanoyl]-L-cysteinyl-D-valine:oxygen oxidoreductase (cyclizing)

Comments: Forms part of the penicillin biosynthesis pathway (for pathway, click here).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 78642-31-6


1. Huffman, G.W., Gesellchen, P.D., Turner, J.R., Rothenberger, R.B., Osborne, H.E., Miller, F.D., Chapman, J.L. and Queener, S.W. Substrate specificity of isopenicillin N synthase. J. Med. Chem. 35 (1992) 1897-1914. [PMID: 1588566]

2. Roach, P.L., Clifton, I.J., Fulop, V., Harlos, K., Barton, G.J., Hajdu, J., Andersson, I., Schofield, C.J. and Baldwin, J.E. Crystal structure of isopenicillin N synthase is the first from a new structural family of enzymes. Nature 375 (1995) 700-704. [PMID: 7791906]

[EC created 2002]

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