生物膜能量偶联ATP酶的研究牛心线粒体F_1冷盐解离后各部分的亚基分析

纯化的牛心线粒体Ｆ１ＡＴＰ酶（Ｆ_１）在有１ｍｏｌ／ＬＫＣｌ的介质中，０℃保温１ｈ，酶活性降到接近于零，经脱盐并在室温（２０—２５℃）保温，可恢复约６０％的酶活性。电泳结果表明，冷盐处理１ｈ的样品解来成了四个亚部分，这四个部分的亚基组成分别是Ⅰ，α，γ，δ，ε，Ⅱ，β，δ，ε，Ⅲ，β，ε，Ⅳ，β。经冷盐处理１ｈ和５ｈ的Ｆ_１进行ＨＰＬＣ分析的结果有显著的差别。

Studies on the Energy-transducing ATPase Complex of Biomembrane:The Subunit Composition of Subfractions Induced by Colt and Salt Treatment of Beef Heart Mitochondria

The activity of F_1-ATPase (F_1) of beef heart mitochondria decreased very rapidly in the medium of 50mM of Tris , ZmM of EDTA,2mM of ATP and 1M of KCl(pH7. 4), at 0─4℃. In the condition as above for one hour, the activity of F_1 decreased to about zero, accompanied by dissociation of F_1 into four subfractions, as confirmed by polyacrylamide gel electrophoresis analysis at 0℃. The subunit composition of the four parts was Ⅰ ,α、γ、δ、ε; Ⅱ ,β、δ、ε;Ⅲ ,β、ε;Ⅳ,β,according to SDS-electrophoresis analysis. The subfractions of F_1 induced by cold treatment in the presence of 1M of KCl were unstable. If the dissociated condition was removed in time, the activity of F_1 could be partially recovered and the structure restored also. If F_1 was in the dissociated condition for five hrs. some subfractions would combine to a large structure , but the activity of F_1 and the structure of it could not be recovered.These results provided that treated F_1 at 0℃ in the presence of iM of KCl would be a good way for preparing the β subunit and the other subunits, which remained the reconstituted property.It also demonstrated that the dissociated process was a dynamic process.