<?xml version="1.0" encoding="utf-8"?><metadata xmlns:dc="http://purl.org/dc/elements/1.1/"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dcterms="http://purl.org/dc/terms/"><dc:title xml:lang="en">cystine</dc:title><dc:identifier>http://AATesaurus.cultura.gencat.cat/aat/getty_en?tema=31344310</dc:identifier><dc:language>en</dc:language><dc:publisher xml:lang="en">Getty Institute</dc:publisher><dcterms:created>2026-03-30 20:32:51</dcterms:created><dcterms:isPartOf xsi:type="dcterms:URI">http://AATesaurus.cultura.gencat.cat/aat/getty_en</dcterms:isPartOf><dcterms:isPartOf xml:lang="en">Tesaurus d&apos;Art i Arquitectura</dcterms:isPartOf><dc:format>text/html</dc:format> <dcterms:alternative xml:lang="en">C6H12N2O4S2</dcterms:alternative> <dc:description xml:lang="en"><![CDATA[ A crystalline, sulfur-containing amino acid that is formed from two molecules of the amino acid cysteine. Cystine can be converted to cysteine by reduction. Cystine is particularly abundant in skeletal and connective tissues and in hair, horn, and wool.  ]]></dc:description></metadata>