PXLP-CBS tetramers condenses HCYS and L-Ser to form L-Cystathionine

Stable Identifier
R-HSA-1614524
Type
Reaction [transition]
Species
Homo sapiens
Compartment
Synonyms
Cystathionine is formed from homocysteine and serine
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The first step of homocysteine conversion to cysteine is catalyzed by cystathionine beta-lyase, which adds a serine molecule to the substrate. The enzyme is a tetramer with two heme molecules as cofactor (Janosik et al. 2001). CBS also utilises pyridoxal 5'-phosphate (PXLP) as cofactor, at the evolutionarily conserved Lys119 residue (Kery et al. 1999). The cystathionine beta-synthase-like protein (CBSL) is thought to function like CBS.

Literature References
PubMed ID Title Journal Year
11524006 Regulation of human cystathionine beta-synthase by S-adenosyl-L-methionine: evidence for two catalytically active conformations involving an autoinhibitory domain in the C-terminal region

Janosík, M, Kery, V, Gaustadnes, M, Maclean, KN, Kraus, JP

Biochemistry 2001
10052942 Binding of pyridoxal 5'-phosphate to the heme protein human cystathionine beta-synthase

Kery, V, Poneleit, L, Meyer, JD, Manning, MC, Kraus, JP

Biochemistry 1999
Participants
Participant Of
Catalyst Activity
Catalyst Activity
Title
cystathionine beta-synthase activity of PXLP-CBS tetramers [cytosol]
Physical Entity
Activity
Orthologous Events
Authored
Reviewed
Created