Kobayashi K
J Biochem. 1982 Mar;91(3):783-92. doi: 10.1093/oxfordjournals.jbchem.a133765.
Crithidia fasciculata, a pterin requiring protozoa, contained a NADPH-dependent dihydro-6-formylpterin reducing enzyme. The aldehyde reductase was purified and characterized. This enzyme was soluble and constitutive, and had the ability to catalyze the interconversion between aldehydes and alcohols. The optimal pH was 7.0 for the reductase activity and 9.0 for the dehydrogenase activity. The enzyme had a broad substrate specificity and reduced aromatic and aliphatic aldehydes such as dihydro-6-formylpterin, benzaldehyde, pyridine-3-aldehyde, butyraldehyde, DL-glyceraldehyde, and acetaldehyde. The enzyme was inhibited by sulfhydryl reagents and heavy metals, but not inhibited by chelating reagents. Its molecular weight was determined to be 66,000 and 72,000 by gel filtration and sedimentation equilibrium analysis, respectively. The value of 39,000 was obtained by sodium dodecyl sulfate gel electrophoresis indicating a dimeric structure. The aldehyde reductase of Crithidia may be classified as NADP+-dependent aryl-alcohol dehydrogenase [EC 1.1.1.91].
丛簇锥虫（Crithidia fasciculata），一种需要蝶呤的原生动物，含有一种依赖NADPH的二氢-6-甲酰蝶呤还原酶。对该醛还原酶进行了纯化和特性鉴定。这种酶是可溶的且组成型表达，具有催化醛与醇之间相互转化的能力。还原酶活性的最适pH为7.0，脱氢酶活性的最适pH为9.0。该酶具有广泛的底物特异性，能还原芳香族和脂肪族醛类，如二氢-6-甲酰蝶呤、苯甲醛、吡啶-3-甲醛、丁醛、DL-甘油醛和乙醛。该酶受到巯基试剂和重金属的抑制，但不受螯合剂的抑制。通过凝胶过滤和沉降平衡分析分别测定其分子量为66,000和72,000。通过十二烷基硫酸钠凝胶电泳得到的值为39,000，表明其为二聚体结构。丛簇锥虫的醛还原酶可归类为依赖NADP⁺的芳基醇脱氢酶[EC 1.1.1.91]。
