title: The case for an early biological origin of DNA.
abstract: All life generates deoxyribonucleotides, the building blocks of DNA, via ribonucleotide reductases (RNRs). The complexity of this reaction suggests it did not evolve until well after the advent of templated protein synthesis, which in turn suggests DNA evolved later than both RNA and templated protein synthesis. However, deoxyribonucleotides may have first been synthesised via an alternative, chemically simpler route--the reversal of the deoxyriboaldolase (DERA) step in deoxyribonucleotide salvage. In light of recent work demonstrating that this reaction can drive synthesis of deoxyribonucleosides, we consider what pressures early adoption of this pathway would have placed on cell metabolism. This in turn provides a rationale for the replacement of DERA-dependent DNA production by RNR-dependent production.
authors.affiliation: Biomolecular Interaction Centre, School of Biological Sciences, University of Canterbury, Christchurch, 8140, New Zealand, anthony.poole@canterbury.ac.nz.
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Poole
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Horinouchi
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Catchpole
authors.forename: Dayong
authors.initials: D
authors.lastname: Si
authors.forename: Makoto
authors.initials: M
authors.lastname: Hibi
authors.forename: Koichi
authors.initials: K
authors.lastname: Tanaka
authors.forename: Jun
authors.initials: J
authors.lastname: Ogawa
mesh_terms: D000446:Aldehyde-Lyases / Q000737:chemistry* / Q000378:metabolism; D005075:Biological Evolution; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D004261:DNA Replication; D003854:Deoxyribonucleotides / Q000737:chemistry / Q000378:metabolism; D056890:Eukaryota / Q000737:chemistry / Q000378:metabolism; D000069497:Origin of Life; D011387:Prokaryotic Cells / Q000737:chemistry / Q000378:metabolism; D012264:Ribonucleotide Reductases / Q000737:chemistry* / Q000378:metabolism; D013997:Time Factors
chemical_list: D003854:Deoxyribonucleotides; D004247:DNA; D012264:Ribonucleotide Reductases; D000446:Aldehyde-Lyases; C020019:deoxyribose-phosphate aldolase