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ENZYME

ENZYME entry: EC 4.4.1.2

Accepted Name
homocysteine desulfhydrase
Alternative Name(s)
homocysteine desulfurase
Reaction catalysed
H2O + L-homocysteine <=> 2-oxobutanoate + H(+) + hydrogen sulfide + NH4(+)
Comment(s)
  • The enzyme cleaves a carbon-sulfur bond, releasing hydrogen sulfide and an unstable enamine product that tautomerizes to an imine form, which undergoes a hydrolytic deamination to form 2-oxobutanoate and ammonia.
  • The latter reaction, which can occur spontaneously, can also be catalyzed by EC 3.5.99.10.
Cross-references
BRENDA4.4.1.2
EC2PDB4.4.1.2
ExplorEnz4.4.1.2
PRIAM enzyme-specific profiles4.4.1.2
KEGG Ligand Database for Enzyme Nomenclature4.4.1.2
IUBMB Enzyme Nomenclature4.4.1.2
IntEnz4.4.1.2
MEDLINEFind literature relating to 4.4.1.2
MetaCyc4.4.1.2
Rhea expert-curated reactions4.4.1.2
UniProtKB/Swiss-Prot
Q55DV9, CGL_DICDIP32929, CGL_HUMANQ60HG7, CGL_MACFA
Q8VCN5, CGL_MOUSEQ19QT7, CGL_PIGP18757, CGL_RAT
O05394, MCCB_BACSUQ8RDT4, MEGL_FUSNNQ8L0X4, MEGL_FUSNP
Q7MX71, MEGL_PORGIP13254, MEGL_PSEPUQ826W3, MEGL_STRAW
Q73KL7, MEGL_TREDE

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All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 4.4.1.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 4.4.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 4.-.-.-