Autocatalytic replication and homochirality in biopolymers: is homochirality a requirement of life or a result of it?

摘要: A key step in the origin of life is establishment autocatalytic cycles controlled by biopolymer catalysts. These catalysts (either ribozymes or proteins) are composed homochiral monomers. Homochirality living systems maintained because biopolymers asymmetric their catalysis and synthesize molecules own handedness. Asymmetric autocatalysis also possible with small molecules, as demonstrated Soai reaction, but it rare. As far we know, single nucleotides amino acids not autocatalytic. The observation that organic meteorites can have an enantiomeric excess a few percent suggests prebiotic mixture may had partial chiral bias was caused external physical influences. Here, consider way such would influence RNA world scenario. We previously shown how transition to state occur model for polymerization. add chirality problem considering simultaneous synthesis polymerization left- right-handed two chemical rates be equal unequal, due effects prior life. determine stationary states this reaction system. nonliving racemic, slightly biased. There almost completely homochiral, whether It feature our that, some regions parameter space, both found stable under same conditions. therefore involves stochastic between states. Our extends previous theories treating aspects model.