title: Origins of the first cell. A new model for the spontaneous formation of the first living cell based on a novel approach.
abstract: Whether proteins or nucleic acids were responsible for the emergence of life has been debated for a long time. Taking the observation that families of proteins display a remarkable invariance of their amino acid sequence around critical regions, such as active/binding sites, even though these proteins may represent considerable evolutionary diversity, as the naturally provided evidence of evoluntionary selection of working system, the idea is developed that: 1. Proteins had to have been first informational macromolecules that were necessary and sufficient to lead to the emergence of life; 2. it is impossible for a nucleic acid molecules to have formed, by chance, whose base sequence could yield a biologically active protein. A model is proposed to account for the emergence of the first successful cell according to this approach.
mesh_terms: D001483:Base Sequence; D005075:Biological Evolution; D002477:Cells; D004247:DNA / Q000096:biosynthesis; D005815:Genetic Code; D008954:Models, Biological; D000069497:Origin of Life; D011336:Probability; D014176:Protein Biosynthesis; D014780:Viruses
chemical_list: D004247:DNA