ICR 종 친근교배계 성숙 생쥐 125마리에서 얻은 간 128.8gm에서 $delta$-ALAD를 Doyle & Schimke(1969)의 변법으로 정제하였던 바, DEAD-cellulose column chromatography 할 때 NaCl 농도 0.05M와 0.2~0.3M에서 유출되는 두 종의 효소분획을 얻었다. 이 두 효소분획을 polyacrylamide disc gel electrophoresis 하여 효소단백질의 이동율로부터 분자량을 산출하였던바, 효소품획 I의 분자량은 174.000이고, 효소분획 II의 분자량은 275,000으로 밝혀졌다. 이상의 성적은 ICR종 친근교배계 쥐의 간 조직내 $delta$-ALAD에는 2개의 동위효소가 존재하고 있음을 시사하였다.
Two different molecular forms of hepatic $delta$-aminolevulinate dehydratase (EC 4.2.1.24) have been isolated and purified by slightly modified method of Doyle and Schimke (1969) on DEAE-cellulose column chromatography by linear gradient elution with 0.4 M NaCl solution from 125 livers of the ICR inbred strain of adult mice. The enzyme fraction I and II were eluted at a NaCI concentration of between 0.05~0.1M, and between 0.2~0.3M, respectively, on the DEAE-cellulose column chromatography, which was equilibrated with 25 mM potassium phospate buffer, pH 6.8 (column size $1{ imes}50;cm$). The specific activity of the enzyme fraction II was 3.5 times as high as that of the enzyme fraction I. Molecular weight for the enzyme fraction I and II was 174,000 and 275,000, respectively, as determined by acrylamide disc gel electrophoresis and by Sephadex G-120-200 gel filtration.
