Whiting M J, Granick S
J Biol Chem. 1976 Mar 10;251(5):1340-6.
The purification of hepatic delta-aminolevulinic acid synthase (EC 2.3.1.37) was accomplished from chick embryo liver mitochondria, which had been treated with the combination of drugs, 2-allylisopropylacetamide and 1,4-dihydro-3,5-dicarbethoxycollidine to produce a high starting level of enzyme activity. After extraction from the mitochondria by sonication, the enzyme was purified to a final specific activity of over 10,000 nmol of aminolevulinate formed/30 min/mg of protein/37 degrees, using the techniques of Sephadex chromatography, ammonium sulfate fractionation, affinity chromatography for pyridoxal phosphate, and preparative isoelectric focusing. An isoelectric point of 7.0 and a molecular weight of 87,000 were obtained for the native enzyme. The subunit molecular weight of 49,000, obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, suggested it was a dimer. The enzyme was inhibited by p-chloromercuribenzoate and N-ethylmaleimide, stimulated by cations and exhibited an ultraviolet absorption spectrum characteristic of pyridoxal 5'-phosphate enzymes with absorption maxima at 325 and 420 nm.
肝δ-氨基乙酰丙酸合酶（EC 2.3.1.37）的纯化是从鸡胚肝线粒体中完成的，该线粒体用药物2-烯丙基异丙基乙酰胺和1,4-二氢-3,5-二乙氧羰基吡啶的组合处理，以产生高起始水平的酶活性。通过超声处理从线粒体中提取后，使用葡聚糖凝胶色谱法、硫酸铵分级分离、磷酸吡哆醛亲和色谱法和制备性等电聚焦技术，将该酶纯化至最终比活性超过10,000 nmol氨基乙酰丙酸形成/30分钟/毫克蛋白质/37℃。天然酶的等电点为7.0，分子量为87,000。通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳获得的亚基分子量为49,000，表明它是二聚体。该酶受到对氯汞苯甲酸和N-乙基马来酰亚胺的抑制，受到阳离子的刺激，并表现出磷酸吡哆醛5'-磷酸酶的紫外吸收光谱特征，吸收峰在325和420 nm处。
