【摘要】 牛蛙心脏中乳酸脱氢酶在聚丙烯酰胺凝胶电泳上显示3种同工酶区带,分别命名为LDH1、LDH2、LDH3,其中LDH1的活力占绝对优势。采用HiTrapTMBlue HP亲和层析和DEAE-Sephadex A离子交换层析对牛蛙骨骼肌中的LDH3进行了分离纯化。纯化的LDH3比活力为295U/mg,Km NADH=0·028,Km丙酮酸=1·242,在SDS-PAGE上显示两条带,提示该同工酶是由两种亚基组成的,亚基的分子量分别为35·3kD和37·6kD。更多还原

【Abstract】 Lactate dehydrogenase of bullfrog heart showed three isozymes on polyacrylamide gel electrophoresis,LDH₁,LDH₂,and LDH₃.LDH₁ exhibited the highest activity.LDH₃ was separated and purified from bullfrog muscle by HiTrap TM Blue HP affinity chromatography and DEAE-Sephadex A ion exchange chromatography.The relative activity of purified LDH₃ was 295 U/mg.Protein kinetic analysis showed that the Michaelis constants（Km）value for NADH was 0.028,and Km value for pyruvate was 1.242.The purified LDH₃ exhibited two bands on SDS-PAGE,with molecular weight of 35.3 kD and 37.6 kD respectively,suggesting that the LDH₃ isozyme be composed of two subunits.更多还原