고도 호열성균 Thermus caldophilus Adenylate Kinase의 정제와 성질

Purification and Characteristics of Adenylate Kinase from Extreme Thermophile Thermus caldophilus GK-24

고도 호열성균의 Adenylate kinase가 phospho cellulose column의 adenosine-penta-phospho adenosine affinity elution으로부터 균일하게 정제되었다. 분자량은 SDS PAGE와 gel filtration으로부터 22,000의 단량체로 밝혀졌다. 효소반응의 최적온도는 8$0^{\circ}C$이였으며 정반응의 활성화 에너지는 22.4kcal/mole이었다. 본 효소는 6M guanidine-HCI에 활성을 잃지 않았으며 10$0^{\circ}C$에서 한시간에 75%의 활성을 유지하였다. AMP, ADP, ATP에 대한 Km치는 0.01mM, 0.017mM, 0.067mM이었다.

The adenylate kinase was purified from an extreme thermophile by adenosine-pentaphospho-adenosine elution from phosphocellulose column. The molecular weight was estimated to be 22,000 by SDS-PAGE and gel filtration. The optimum temperature of the enzyme activity was 8$0^{\circ}C$ and the activation energy was given as 22.4 kcal/mole. The enzyme even showed full activity after incubation at 9$0^{\circ}C$ or in 6M guanidine-HCI at 3$0^{\circ}C$ and retained 75% of its original activity even after 1 hour at 10$0^{\circ}C$. The Michaelis constants of the enzymes for AMP, ADP, and ATP were 0.01mM, 0.017mM and 0.067mM, respectively.