title: A specific scenario for the origin of life and the genetic code based on peptide/oligonucleotide interdependence.
abstract: Among various scenarios that attempt to explain how life arose, the RNA world is currently the most widely accepted scientific hypothesis among biologists. However, the RNA world is logistically implausible and doesn't explain how translation arose and DNA became incorporated into living systems. Here I propose an alternative hypothesis for life's origin based on cooperation between simple nucleic acids, peptides and lipids. Organic matter that accumulated on the prebiotic Earth segregated into phases in the ocean based on density and solubility. Synthesis of complex organic monomers and polymerization reactions occurred within a surface hydrophilic layer and at its aqueous and atmospheric interfaces. Replication of nucleic acids and translation of peptides began at the emulsified interface between hydrophobic and aqueous layers. At the core of the protobiont was a family of short nucleic acids bearing arginine's codon and anticodon that added this amino acid to pre-formed peptides. In turn, the survival and replication of nucleic acid was aided by the peptides. The arginine-enriched peptides served to sequester and transfer phosphate bond energy and acted as cohesive agents, aggregating nucleic acids and keeping them at the interface.
authors.affiliation: Department of Biology, University of Massachusetts Dartmouth, North Dartmouth, 02747, USA. rgriffith@umassd.edu
authors.forename: Robert W
authors.initials: RW
authors.lastname: Griffith
mesh_terms: D000926:Anticodon / Q000235:genetics / Q000378:metabolism; D001120:Arginine / Q000235:genetics / Q000378:metabolism; D003062:Codon / Q000235:genetics / Q000378:metabolism; D018534:Earth, Planet; D004735:Energy Transfer / Q000235:genetics; D019143:Evolution, Molecular; D005815:Genetic Code; D057927:Hydrophobic and Hydrophilic Interactions; D019369:Life; D009792:Oceans and Seas; D009841:Oligonucleotides / Q000235:genetics / Q000378:metabolism; D000069497:Origin of Life; D010455:Peptides / Q000235:genetics / Q000378:metabolism; D010710:Phosphates / Q000737:chemistry; D058105:Polymerization; D012313:RNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012995:Solubility; D013046:Specific Gravity; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D000926:Anticodon; D003062:Codon; D009841:Oligonucleotides; D010455:Peptides; D010710:Phosphates; D013501:Surface-Active Agents; D012313:RNA; D001120:Arginine