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B6db activities:
Description Cystathionine gamma-synthase
Alternative names O-succinylhomoserine (thiol)-lyase;
Homoserine transsuccinylase.;
Cystathionine synthase;
Catalyzed reaction O-succinyl-L-homoserine + L-cysteine = cystathionine + succinate.
Cofactor Pyridoxal-phosphate.
Comments -!- Can also use hydrogen sulfide and methanethiol as substrates producing homocysteine and methionine respectively.
-!- In the absence of thiol, can also catalyse beta,gamma-elimination to form 2-oxobutanoate, succinate and ammonia.

The plant enzyme can also use O-phosphohomoserine as a substrate.

Formerly EC

Subfamily includes enzymes from gram-negative bacteria; subfamily b encompasses enzymes from plants (plastidial proteins) and cyanobacteria.
Prosite PROSITE; PDOC00677;
PDB 1I48; 1I43; 1I41; 1CS1; 1QGN;
Organisms -Eubacteria -Archea -Plants -Fungi


Links Enzyme (activities)
BRENDA (activities)
KEGG (pathways)
PLPMDB (PLP mutants)
 Kong Y, Wu D, Bai H, Han C, Chen J, Chen L, Hu L, Jiang H, Shen X. (2008) Enzymatic characterization and inhibitor discovery of a new cystathionine {gamma}-synthase from Helicobacter pylori J Biochem 143 59-68.

 Steegborn, C.; Messerschmidt, A.; Laber, B.; Streber, W.; Huber, R.; Clausen, T. (1999) The crystal structure of cystathionine gamma-synthase from Nicotiana tabacum reveals its substrate and reaction specificity J Mol Biol 290 983-96.

 Ravanel, S.; Gakiere, B.; Job, D.; Douce, R. (1998) Cystathionine gamma-synthase from Arabidopsis thaliana: purification and biochemical characterization of the recombinant enzyme overexpressed in Escherichia coli Biochem J 331 639-48.

 Wahl, M. C.; Huber, R.; Prade, L.; Marinkovic, S.; Messerschmidt, A.; Clausen, T. (1997) Cloning, purification, crystallization, and preliminary X-ray diffraction analysis of cystathionine gamma-synthase from E. coli FEBS Lett 414 492-6.

Articles on
last changed 2010/01/27 18:06

B6db activities