I269S와 I224S 이중변이 알코올 탈수소효소의 특성

• 영문명: The Characteristics of I269S and I224S Double Mutant Horse Liver Alcohol Dehydrogenase
• 발행기관: 대한약학회
• 저자명: 류지원(Ji Won Ryu) 이강만(Kang Man Lee)
• 간행물 정보: 『약학회지』제41권 제6호 (1997년), 756~764쪽, 전체 9쪽
• 주제분류: 의약학 > 기타의약학
• 파일형태: PDF
• 발행일자: 1997.12.31

영문 초록

Ile-224 in I269S mutant horse liver alcohol dehydrogenase isoenzyme S (HLADH-S) was mutated to serine by site-directed mutagenesis in order to study the role of the residue in coenzyme binding to the enzyme. The specific activity of the I269S and I224S mutant enzyme to ethanol was increased 6-fold and all Michaelis constants(Ka, Kb, Kp, and Kq) were larger than those for the wild-type and I269S enzyme. The substitution decreased the afffinity to coenzymes and increased the specific activity of the enzyme. The mutant enzyme showed the highest catalytic efficiency for octanol among the primary alcohols. But it didn`t have activities on retinoids and 5-beta-cholanic acid-3-one. From these results, it was confirmed that the hydrophobic interaction of Ile-224 residue with coenzyme was related to coenzyme affinity in ADH reaction. The substitution also affected the substrate affinities to the enzyme.

키워드

I269S & I224S double mutant HLADH isoenzyme S.