Abstract
The extant genetic machinery revolves around three interrelated polymers: RNA, DNA and proteins. Two evolutionary views approach this vital connection from opposite perspectives. The RNA World theory posits that life began in a cold prebiotic broth of monomers with the de novo emergence of replicating RNA as functionally self-contained polymer and that subsequent evolution is characterized by RNA → DNA memory takeover and ribozyme → enzyme catalyst takeover. The FeS World theory posits that life began as an autotrophic metabolism in hot volcanic-hydrothermal fluids and evolved with organic products turning into ligands for transition metal catalysts thereby eliciting feedback and feed-forward effects. In this latter context it is posited that the three polymers of the genetic machinery essentially coevolved from monomers through oligomers to polymers, operating functionally first as ligands for ligand-accelerated transition metal catalysis with later addition of base stacking and base pairing, whereby the functional dichotomy between hereditary DNA with stability on geologic time scales and transient, catalytic RNA with stability on metabolic time scales existed since the dawn of the genetic machinery. Both approaches are assessed comparatively for chemical soundness.
Highlights
Metabolism, genetics and cellularity of life are closely interrelated
We evaluate these accounts along Popperian lines for their relative explanatory power [1], their compatibility with the logic of the chemical situation, and their aptitude to grow in comprehensiveness and coherence by the integration of independently developed evolutionary theorems based on extant biochemistry and genetics
The extant biosphere is spread over a wide range of growth temperatures, which poses a crucial question [32]: What is the direction of evolution of the optimum growth temperature of organisms—Is it reversible or irreversible? Phylogenetic considerations suggest a hyperthermophilic origin, but they are inconclusive from a formal point of view
Summary
Metabolism, genetics and cellularity of life are closely interrelated. Genetics imposes catalytic control on the metabolism, yet its components derive from this very metabolism. The cell structure derives from the genetically controlled metabolism, yet it is required to hold genetics and metabolism together. Thereafter we interpolate between LUCA on the one side and competing theories of the origin of life on the other side This evolutionary interpolation provides us with competing accounts of early evolution. We evaluate these accounts along Popperian lines for their relative explanatory power [1], their compatibility with the logic of the chemical situation, and their aptitude to grow in comprehensiveness and coherence by the integration of independently developed evolutionary theorems based on extant biochemistry and genetics. When we can demonstrate an orderly course of progress, each advance building on previous advances and giving rise to further advances, we shall know that we are on the road to a mature science
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
