A coupled enzyme assay for isopenicillin N synthetase.

@article{Baldwin1985ACE,
  title={A coupled enzyme assay for isopenicillin N synthetase.},
  author={Jack E. Baldwin and Simon E. Moroney and Henry H. Ting},
  journal={Analytical biochemistry},
  year={1985},
  volume={145 1},
  pages={183-7}
}
The development of a coupled enzyme assay for the determination of isopenicillin N synthetase activity in purified extracts from Cephalosporium acremonium was described. Isopenicillin N formed from its precursor, delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine (ACV), by the synthetase was hydrolyzed by beta-lactamase I to the corresponding penicilloic acid. Automatic titration of the acid with standard sodium hydroxide delivered by a pH-stat gave a continuous plot of product formed vs time… CONTINUE READING