Bernard N, Johnsen K, Holbrook J J, Delcour J
Unité de Génétique, Université Catholique de Louvain, Louvain-la-Neuve, Belgium.
Biochem Biophys Res Commun. 1995 Mar 28;208(3):895-900. doi: 10.1006/bbrc.1995.1419.
The NAD-dependent D-(-)-lactate dehydrogenase (D-LDH) from Lactobacillus delbrueckii subsp. bulgaricus (in short, L. bulgaricus) has been modified at position 175 by site-directed mutagenesis, changing a conserved aspartate residue into an alanine. The D175A mutant enzyme displays a 40-fold shift in coenzyme preference from NADH to NADPH. This demonstrates that D175 truly belongs to the amino acid consensus GXGXXGX(17)D (where X represents any residue) which is the signature of the coenzyme binding site of most NAD-dependent dehydrogenases.
来自德氏乳杆菌保加利亚亚种（简称为保加利亚乳杆菌）的NAD依赖性D-(-)-乳酸脱氢酶（D-LDH）在第175位通过定点诱变进行了修饰，将一个保守的天冬氨酸残基变为丙氨酸。D175A突变酶的辅酶偏好从NADH到NADPH发生了40倍的转变。这表明D175确实属于氨基酸共有序列GXGXXGX(17)D（其中X代表任何残基），这是大多数NAD依赖性脱氢酶辅酶结合位点的特征。
