title: Coenzymes as fossils of an earlier metabolic state.
abstract: A metabolic system composed of nucleic acid enzymes is proposed to have existed prior to the evolution of ribosomal protein synthesis. Vestiges of these nucleic acid enzymes persist in contemporary coenzymes. This proposal rationalizes the fact that many coenzymes are nucleotides or heterocyclic bases which could be derived from nucleotides.
mesh_terms: D005075:Biological Evolution; D003067:Coenzymes / Q000378:metabolism*; D004261:DNA Replication; D005580:Fossils; D005796:Genes; D010163:Paleontology; D014158:Transcription, Genetic
chemical_list: D003067:Coenzymes