Mapping Geological Events and Nitrogen Fixation Evolution Onto the Timetree of the Evolution of Nitrogen-Fixation Genes

• Published in: Molecular biology and evolution Vol. 41; no. 2
• Main Authors: Pi, Hong-Wei, Chiang, Yin-Ru, Li, Wen-Hsiung
• Format: Journal Article
• Language: English
• Published: US Oxford University Press 01.02.2024
• Subjects: Bacteria; Calibration; Cyanobacteria; Discoveries; Evolution; Evolutionary genetics; Fixation; Gene mapping; Genes; Geological mapping; Geology; Hypotheses; Maximum likelihood method; Nitrogen; Nitrogen fixation; Nitrogenase; Nitrogenation; Oxidation; Prokaryotes; Proteins; Taiwan; biological nitrogen fixation; geological event; timetree; nitrogenase
• ISSN: 0737-4038; 1537-1719; 1537-1719
• DOI: 10.1093/molbev/msae023

Abstract Nitrogen is essential for all organisms, but biological nitrogen fixation (BNF) occurs only in a small fraction of prokaryotes. Previous studies divided nitrogenase-gene-carrying prokaryotes into Groups I to IV and provided evidence that BNF first evolved in bacteria. This study constructed a timetree of the evolution of nitrogen-fixation genes and estimated that archaea evolved BNF much later than bacteria and that nitrogen-fixing cyanobacteria evolved later than 1,900 MYA, considerably younger than the previous estimate of 2,200 MYA. Moreover, Groups III and II/I diverged ∼2,280 MYA, after the Kenorland supercontinent breakup (∼2,500–2,100 MYA) and the Great Oxidation Event (∼2,400–2,100 MYA); Groups III and Vnf/Anf diverged ∼2,086 MYA, after the Yarrabubba impact (∼2,229 MYA); and Groups II and I diverged ∼1,920 MYA, after the Vredefort impact (∼2,023 MYA). In summary, this study provided a timescale of BNF events and discussed the possible effects of geological events on BNF evolution.