The Degradation of Cystine Peptides by Tissues

Abstract
Exocystine peptides, digested with rat liver extracts, were degraded under controlled conditions to pyruvic acid, NH3 and H2S. Cystine (or cysteine) was the natural precursor of dehydropeptides (DHP). Evidence was given to show that exocystine peptides yielded the corresponding DHP probably by desulfuration followed by hydrolysis of DHP to the principal products of pyruvic acid and NH3. The enzyme causing desulfuration was designated "exocystine desulfurase.".