【作者】 陈圣福； 徐磊； 欧阳振乾； 张益； 李民乾； 洪国藩；

【Author】 Chen Shengfu Xu Lei Ouyang Zhenqian Zhang Yi Li Minqian (Shanghai Institute of Nuclear research,Chinese Academy of Sciences,Shanghai 201800) Hong Guofan (Shanghai Institute of Biochemistry,Chinese Academy of Sciences,Shanghai 200031)

【机构】 中国科学院上海原子核研究所； 中国科学院上海生物化学研究所；

【摘要】 本文利用原子力显微镜(AFM),对高温 DNA 聚合酶Ⅰ和普通 E．coli 的 DNA 聚合酶Ⅰ的 Klenow 片段在乙醇中变性的对比研究,发现在两种 DNA 聚合酶中都存在结构较紧密的“核”。通过对吸附在云母上的两种酶进行1—10个小时的处理发现高温聚合酶大多由3块“核”组成,而普通的 DNA 聚合酶由2块“核”组成。这些“核”可能与蛋白的折叠过程中存在的相对稳定的结构区域有关, 这对直观了解蛋白折叠过程有一定意义。更多还原

【Abstract】 Atomic Force Microscopy(AFM)has been used to study the changes of main structure in the denaturating process of Bacillus stearothermophilus T-3468 DNA polymerase I Klenow Fragment(Bet pol I KF)and its ho- mologous protein(Escherichia coli DNA polymerase Klenow Fragment)in alcohol.For comparison,images of Bst pol I KF have also been obtained by tapping mode AFM in air,and its contour looks like a kidney or a pear, which is similar to that of Escherichia coli DNA polymerase I Klenow Fragment obtained by X-ray diffraction. After treated by alcohol for 2 hours on mica,main structure of the two kinds of fragments relaxed relatively,and after 10 hours manifested two domains formed by two or three parts,which suggests that there are similar cores which may be relative to folding cores in two kinds of homologous protein in pure alcohol and this method is a useful tool for large monomer protein folding.更多还原