a crystalline amino acid, C6H12O4N2S2, occurring in most proteins, especially the keratins in hair, wool, and horn, and yielding cysteine on reduction.
Origin of cystine
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for cystine
Historical Examples of cystine
a sulphur-containing amino acid present in proteins: yields two molecules of cysteine on reduction. Formula: HOOCCH(NH 2)CH 2 SSCH 2 CH(NH 2)COOH
Word Origin for cystine
C19: see cysto- (bladder), -ine ²; named from its being discovered in a type of urinary calculus
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
A white crystalline amino acid that is found in many proteins, especially keratin, and is the major source of metabolic sulfur.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.