Spectrophotometric cysteine analysis.
نویسندگان
چکیده
Procedures have been developed for estimating cystine content of proteins by reducing disulfide bonds with mercaptoethanol and selectively alkylating the generated sulfhydryl groups with 4-vinylpyridine or 2-vinylquinoline. 4-Vinylpyridine reacts with cysteine to produce S-,B-(4-pyridylethyl)cysteine (Pe-cysteine), which can be determined in protein hydrolysates either by ion-exchange chromatography or ultraviolet spectrophotometry. Pecysteine cannot be determined spectrophotometrically in the intact protein, since the absorp-
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عنوان ژورنال:
- Journal of agricultural and food chemistry
دوره 20 6 شماره
صفحات -
تاریخ انتشار 1972