Reaction of cystine with tryptophan under the conditions of acid hydrolysis of proteins: Mechanism of action of cystine.
- 1 January 1979
- journal article
- Published by Oxford University Press (OUP) in Agricultural and Biological Chemistry
- Vol. 43 (12) , 2419-2423
- https://doi.org/10.1271/bbb1961.43.2419
Abstract
Heating of cystine under the conditions usually used for the HCl-hydrolysis of proteins gave a small amount of bis-(2-amino-2-carboxyethyl) trisulfide (CTS). Tryptophan was great-ly degraded by the reaction with CTS under these conditions. This reaction was inhibited by thioglycolic acid or hydroquinone, indicating that it involves a free-radical mechanism. The known reaction of cystine with tryptophan under the same conditions, however, was inhibited by only thioglycolic acid. From these results, it is supposed that sulfenium ion (+SCH2CH(NH2)COOH), not CTS, arising from cystine is mainly responsible for the loss of tryptophan during the acid hydrolysis of proteins.Keywords
This publication has 0 references indexed in Scilit: