Giannoni G, Padden F J, Keith H D
Proc Natl Acad Sci U S A. 1969 Mar;62(3):964-71. doi: 10.1073/pnas.62.3.964.
Hexagonal platelet crystals about 1 mu across and about 150 A thick have been precipitated by the addition of ethanol to solutions of ultrasonically degraded, salmon sperm DNA in sodium cacodylate buffer. X-ray powder diffraction patterns from concentrated slurries of these crystals in mother liquor show intense rings at 23.9 A and at about 3.4 A; the former arise from lateral packing and the latter from an axial periodicity of the DNA helix. Evidence is presented to indicate that native DNA helices crystallize by chain folding and that no irreversible denaturation results from the crystallization process.
通过向超声降解的鲑鱼精子DNA的二甲胂酸钠缓冲溶液中加入乙醇,沉淀出了直径约1微米、厚度约150埃的六角形血小板晶体。这些晶体在母液中的浓缩浆液的X射线粉末衍射图谱在23.9埃和约3.4埃处显示出强烈的环;前者源于侧向堆积,后者源于DNA螺旋的轴向周期性。有证据表明天然DNA螺旋通过链折叠结晶,并且结晶过程不会导致不可逆的变性。