摘要
在综述生物大分子手性起源的各种理论的基础上，提出了手性起源的三步理论，即：１）β蜕变电子弱电协同作用引发１０－６的手性；２）经过化学动力学放大手性至１０－２；３）聚合过程进一步提高手性，并与原始生命共同进化达到１００％的手性，指出手性进化的完成是在３８～３５亿年前，从建设性突变（ａｎａｓｔｒｏｐｈｅ）产生核酸手性，破坏性突变（ｃａｔａｓｔｒｏｐｈｅ）产生氨基酸手性，可以解释氨基酸为Ｌ型，核糖为Ｄ型．讨论了手性系统的进化。
A three step theory on the origin of biochirality is proposed.The first step is:the weakelectromagnetic interaction induced by beta electrons produces the polarization of macromolecules in the order of 10 -6 .Then the amplification of asymmetry by chemical dynamics causes the polarization of 10 -2 .At last,the polymerization process enhances the chirality further.It coevolves with primitive life and finally,produces polarization of 100% which occurred from perhaps 3.8 to perhaps 3.5 Ga ago.It is suggested that the chirality for nucleic acid comes from anastrophy but that for amino acid from catastrophe ( D amino acid decomposes more fastly than L type under the irridiation of beta electrons).This explains the D ribose and L amino acid.The evolution of chiral system is also discussed.It is shown that the theorem on minimum entropy production still holds for biological system with local equilibrium and with extreme asymmetry between thermodynamical current and force,though the Onsager reolations have been broken for this chiral system.
出处
《内蒙古大学学报（自然科学版）》
CAS
CSCD
1998年第3期354-365,共12页
Journal of Inner Mongolia University：Natural Science Edition
基金
国家自然科学基金
关键词
生物手性
β蜕变电子
化学动力学
生物大分子
biochirality beta electron chemical dynamics polymerization anastrophe minimum entropy production
