Reaction: O4-succinyl-L-homoserine + L-cysteine = L-cystathionine + succinate
For diagram of reaction click here.
Other name(s):O-succinyl-L-homoserine succinate-lyase (adding cysteine); O-succinylhomoserine (thiol)-lyase; homoserine O-transsuccinylase (ambiguous); O-succinylhomoserine synthase; O-succinylhomoserine synthetase; cystathionine synthase; cystathionine synthetase; homoserine transsuccinylase (ambiguous); 4-O-succinyl-L-homoserine:L-cysteine S-(3-amino-3-carboxypropyl)transferase
Systematic name: O4-succinyl-L-homoserine:L-cysteine S-(3-amino-3-carboxypropyl)transferase
Comments: A pyridoxal-phosphate protein. Also reacts with hydrogen sulfide and methanethiol as replacing agents, producing homocysteine and methionine, respectively. In the absence of thiol, can also catalyse β,γ-elimination to form 2-oxobutanoate, succinate and ammonia.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9030-70-0
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