>4UUU_1|Chains A, B|CYSTATHIONINE BETA-SYNTHASE|HOMO SAPIENS (9606) MHHHHHHSSGVDLGTENLYFQSMKPWWWHLRVQELGLSAPLTVLPTITCGHTIEILREKGFDQAPVVDEAGVILGMVTLGNMLSSLLAGKVQPSDQVGKVIYKQFKQIRLTDTLGRLSHILEMDHFALVVHEQQRQMVFGVVTAIDLLNFVAAQE