Wattis Jonathan A D, Coveney Peter V
Theoretical Mechanics, School of Mathematical Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
Orig Life Evol Biosph. 2005 Jun;35(3):243-73. doi: 10.1007/s11084-005-0658-7.
We propose a model for chiral polymerisation and investigate its symmetric and asymmetric solutions. The model has a source species which decays into left- and right-handed types of monomer, each of which can polymerise to form homochiral chains; these chains are susceptible to 'poisoning' by the opposite-handed monomer. Homochiral polymers are assumed to influence the proportion of each type of monomer formed from the precursor. We show that for certain parameter values a positive feedback mechanism makes the symmetric steady-state solution unstable. The kinetics of polymer formation are then analysed in the case where the system starts from zero concentrations of monomers and chains. We show that following a long induction time, extremely large concentrations of polymers are formed for a short time, during this time an asymmetry introduced into the system by a random external perturbation may be massively amplified. The system then approaches one of the steady-state solutions described above.
我们提出了一种用于手性聚合的模型，并研究了其对称解和非对称解。该模型有一个源物种，它衰变成左旋和右旋两种类型的单体，每种单体都可以聚合成同手性链；这些链易受相反手性单体的“毒害”。假设同手性聚合物会影响由前体形成的每种单体的比例。我们表明，对于某些参数值，正反馈机制会使对称稳态解变得不稳定。然后在系统从单体和链的零浓度开始的情况下分析聚合物形成的动力学。我们表明，经过很长的诱导时间后，会在短时间内形成极高浓度的聚合物，在此期间，由随机外部扰动引入系统的不对称性可能会被大幅放大。然后系统会趋近于上述稳态解之一。
