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EC number3.5.3.7
CAS number9013-69-8
IntEnzIntEnz view
ExPASyNiceZyme view
MetaCycmetabolic pathway
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO

In enzymology, a guanidinobutyrase (EC is an enzyme that catalyzes the chemical reaction

4-guanidinobutanoate + H2O 4-aminobutanoate + urea

Thus, the two substrates of this enzyme are 4-guanidinobutanoate and H2O, whereas its two products are 4-aminobutanoate and urea.

This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amidines. The systematic name of this enzyme class is 4-guanidinobutanoate amidinohydrolase. Other names in common use include gamma-guanidobutyrase, 4-guanidinobutyrate amidinobutyrase, gamma-guanidinobutyrate amidinohydrolase, G-Base, GBH, and guanidinobutyrate ureahydrolase. This enzyme participates in urea cycle and metabolism of amino groups. It employs one cofactor, manganese.


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