소의 간 미토콘드리아의 matrix 분획으로부터 aldehyde dehydrogenase(EC 1.2.1.3, ALDH)를 황산암모늄 분별침전, DEAE-Sephacel, hydroxyapatite, blue-Sepharose CL-6B column chromatography로 정제하였다. S-300 gel filtration 방법으로 측정한 이 효소의 분자량은 230,000 dalton이고, 이 효소의 subunit을 SDS-polyacrylamide gel 전기이동법으로 조사한 결과 동일한 subunit(분자량 : 57,400 dalton)으로 구성된 homotetramer임을 알 수 있었다. 이 효소의 최적 pH는 9.5였고, $25{sim}37^{circ}C$에서 매우 안정하였다. Acetaldehyde와 propionaldehyde에 대한 $K_m$값은 각각 $9.6{mu}M$, $6.5{mu}M$이었으나 succinic semialdehyde나 indole-3-acetaldehyde에 대한 반응성은 매우 낮았고, 방향족 aldehyde에 대해서는 전혀 반응을 하지 않았다. 따라서 이 효소는 주로 short chain aliphatic aldehyde의 대사에 관여하는 것으로 생각된다.
Bovine liver mitochodrial matrix aldehyde dehydrogenase (ALDH) was purified by ammonium sulfate precipitation, DEAE-Sephacel, hydroxyapatite and blue-Sepharose CL-6B column chromatography. The molecular weight of this enzyme was determined to be 230 KDa by S-300 gel filtration and it was realized that this enzyme was consisted of four identical subunits and molecular weight of its subunit was found to be 57.4 KDa by SDS-polyacrylamide gel electrophoresis, indicating that this enzyme is homotetramer. This ALDH was stable at $25{sim}37^{circ}C$ and its optimum pH was 9.5. The $K_m$ values of this enzyme for acetaldehyde and propionaldehyde were $9.6{mu}M$ and $6.5{mu}M$ respectively but $K_m$ values for biogenic aldehydes such as succinic semialdehyde and indole-3-acetaldehyde were relatively high ($10^{-4}$ mM level), but not reactive with aromatic aldehydes, suggesting that this enzyme might participate mainly in the oxidation of short chain aliphatic aldehydes.
