The isolation of two proteinases in crystalline form from extracts of beef pancreas has been described by Kunitz and Northrop (1). These enzymes have been named trypsin and chymotrypsin. Previous publications (2) from this laboratory have reported the finding of a series of synthetic peptide derivatives which were readily hydrolyzed by crystalline chymotrypsin. In this communication a synthetic substrate for crystalline trypsin is described. or-Benzoyl-Larginineamide hydrochloride (I) is hydrolyzed extremely rapidly by crystalline trypsin (recrystallized three times) to yield benzoyl-Z-arginine and ammonia (cf. Table I). This hydrolysis proceeds optimally at about pH 7.8 (Fig. 1).

Annals of the New York Academy of SciencesVolume 45, Issue 9 p. 409-423 THE SIGNIFICANCE OF COUPLED REACTIONS FOR THE ENZYMATIC HYDROLYSIS AND SYNTHESIS OF PROTEINS Max Bergmann, Max Bergmann Rockeleller Institute for Medical Research, New York, N. Y.Search for more papers by this authorJoseph S. Fruton, Joseph S. Fruton Rockeleller Institute for Medical Research, New York, N. Y.Search for more papers by this author Max Bergmann, Max Bergmann Rockeleller Institute for Medical Research, New York, N. Y.Search for more papers by this authorJoseph S. Fruton, Joseph S. Fruton Rockeleller Institute for Medical Research, New York, N. Y.Search for more papers by this author First published: November 1944 https://doi.org/10.1111/j.1749-6632.1944.tb47960.xCitations: 42AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume45, Issue9Energy Relationships in Enzyme ReactionsNovember 1944Pages 409-423 RelatedInformation

The use of p-hydroxybenzaldehyde in place of benzaldehyde makes accessible .peptidescontaining the dehydrogenated tyrosine residue.

Papain contains a cysteine-activatable proteinase that hydrolyzes benzoyll-arginlneamide (1). This enzyme has been shown to have a specificity similar to that of crystalline pancreatic trypsin (2) and therefore has been designated papain trypsinase (3). Previous experiments have shown that papain trypsinase exists in two inactive forms which can be designated papain-a-trypsinase and papain-13-trypsinase (4). Only the 13-trypsinase can be activated by HCN. However, a-trypsinase can be transformed into the 13-form by minute amounts of sulfhydryl compounds such as H~S or cysteine. The activation of the 0-form by an excess of HCN or H~S is completely reversed when the activator is removed in vacuo. These results have been interpreted to indicate that the reversible activation of papain-fl-trypsinase consists in the formation of dissociable activator-13-trypsinase compounds, as represented below.