On producing more complexity than entropy in replication.
RNA replication in the bacteriophage Q beta system can, in principle, transmit sequence complexity at a higher rate than it increases entropy. Expanding the variety of nucleotides, through novel base-pair interactions, would move the threshold at which synthesis produces more complexity than entropy away from near equilibrium while accelerating the system approach to equilibrium. A decrease in sequence complexity during polymerization, leading to a many-to-one monomer correspondence with template, cannot be reversed, owing to symmetry restrictions. In terms of the kinetic mechanism, uncertainty associated with the the path of depolymerization yields a path entropy which selectively prolongs the reverse reaction. Together with an elevation in thermodynamic entropy, therefore, there are two possible sources of irreversibility in a physical process. Some implications of kinetic irreversibility are considered in relation to the second law of thermodynamics and to the processing and translation of mRNA.
Davis
B K
BK
Research Foundation of Southern California, Inc., La Jolla 92037.
D017908:Allolevivirus / Q000378:metabolism*; D001703:Biophysics / Q000379:methods; D016679:Genome, Viral; D007700:Kinetics; D008433:Mathematics; D008954:Models, Biological; D011777:Q beta Replicase / Q000378:metabolism; D012313:RNA / Q000096:biosynthesis*; D012367:RNA, Viral / Q000096:biosynthesis*; D013816:Thermodynamics; D013997:Time Factors
D012367:RNA, Viral; D012313:RNA; D011777:Q beta Replicase