EC 1.1.1.61     
Accepted name: 4-hydroxybutyrate dehydrogenase
Reaction: 4-hydroxybutanoate + NAD+ = succinate semialdehyde + NADH + H+
Other name(s): γ-hydroxybutyrate dehydrogenase
Systematic name: 4-hydroxybutanoate:NAD+ oxidoreductase
References:
1.  Nirenberg, M.W. and Jakoby, W.B. Enzymatic utilization of γ-hydroxybutyric acid. J. Biol. Chem. 235 (1960) 954–960. [PMID: 14427301]
[EC 1.1.1.61 created 1965]