DURING investigations in this Department on the separation of the components of the proteolytic system of the thyroid gland, a proteinase, substantially purified, was iso1ated. l This fraction also exhibited limited peptidase activity, when tested with a range of peptides,
![L-Phenylalanine,N-[N-[(phenylmethoxy)carbonyl]-S-(phenylmethyl)-L-cysteinyl]-, methyl ester(9CI) Structure](https://image.chemsrc.com/caspic/220/7625-12-9.png)