Aalén N, Steen I H, Birkeland N K, Lien T
Department of Microbiology, University of Bergen, Norway.
Arch Microbiol. 1997 Dec;168(6):536-9. doi: 10.1007/s002030050533.
NADP+-specific glutamate dehydrogenase (EC 1.4.1.4) was purified to homogeneity from the extremely thermophilic, strictly anaerobic, sulfate-reducing archaeon Archaeoglobus fulgidus strain 7324. The native enzyme (263 kDa) is composed of subunits of mol. mass 46 kDa, suggesting a hexameric structure. The temperature optimum for enzyme activity was > 95 degrees C. The enzyme was highly thermostable, having a half-life of 140 min at 100 degrees C. Potassium phosphate, KCl, and NaCl enhanced the thermal stability and increased the rate of activity three- to fourfold. The N-terminal 26-amino-acid sequence showed a high degree of similarity to glutamate dehydrogenases from Pyrococcus spp. and Thermococcus spp.
从极端嗜热、严格厌氧、硫酸盐还原古菌富铁嗜热栖热菌7324菌株中纯化出了烟酰胺腺嘌呤二核苷酸磷酸（NADP⁺）特异性谷氨酸脱氢酶（EC 1.4.1.4），使其达到了均一性。天然酶（263 kDa）由分子量为46 kDa的亚基组成，表明其为六聚体结构。酶活性的最适温度>95℃。该酶具有高度的热稳定性，在100℃下的半衰期为140分钟。磷酸钾、氯化钾和氯化钠增强了热稳定性，并使活性速率提高了三到四倍。N端的26个氨基酸序列与嗜热栖热菌属和嗜热栖热球菌属的谷氨酸脱氢酶具有高度相似性。
