ID 4.4.1.35 DE L-cystine beta-lyase. CA H2O + L-cystine = NH4(+) + pyruvate + S-sulfanyl-L-cysteine. CC -!- The enzyme cleaves a carbon-sulfur bond, releasing L-thiocysteine and CC an unstable enamine product that tautomerizes to an imine form, which CC undergoes a hydrolytic deamination to form pyruvate and ammonia. CC -!- The latter reaction, which can occur spontaneously, can also be CC catalyzed by EC 3.5.99.10. CC -!- The enzyme from Brassica oleracea var. italica (broccoli) does not CC act on cysteine or cystathionine. DR Q9SUR6, CORI3_ARATH; //