A pure enzyme catalyzing penicillin biosynthesis

Science. 1984 May 11;224(4649):610-2. doi: 10.1126/science.6546810.


Isopenicillin N synthetase (cyclase) has been purified to homogeneity from Cephalosporium acremonium strain C-10. The enzyme has a molecular weight of 40,000 to 42,000 and yields a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme was purified in 10 percent yield by a combination of protamine sulfate and ammonium sulfate precipitations, gel filtration, and ion-exchange high-performance liquid chromatography. The purified enzyme can be stabilized with sucrose and stored at -20 degrees C for several weeks without any loss in activity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acremonium / enzymology
  • Chromatography, Gel
  • Chromatography, High Pressure Liquid
  • Electrophoresis, Polyacrylamide Gel
  • Enzymes / isolation & purification*
  • Enzymes / metabolism
  • Oxidoreductases*
  • Penicillins / biosynthesis*


  • Enzymes
  • Penicillins
  • Oxidoreductases
  • isopenicillin N synthetase
  • penicillin N