Dating ammonia-oxidizing bacteria with abundant eukaryotic fossils
Date
22/05/2024Metadata
Show full item recordAbstract
Evolution of a complete nitrogen (N) cycle relies on the onset of ammonia oxidation, which aerobically converts ammonia to nitrogen oxides. However, accurate estimation of the antiquity of ammonia-oxidizing bacteria (AOB) remains challenging because AOB-specific fossils are absent and bacterial fossils amenable to calibrate molecular clocks are rare. Leveraging the ancient endosymbiosis of mitochondria and plastid, as well as using state-of-the-art Bayesian sequential dating approach, we obtained a timeline of AOB evolution calibrated largely by eukaryotic fossils. We show that the first AOB evolved in marine Gammaproteobacteria (Gamma-AOB) and emerged between 2.1 and 1.9 billion years ago (Ga), thus postdating the Great Oxidation Event (GOE; 2.4 to 2.32 Ga). To reconcile the sedimentary N isotopic signatures of ammonia oxidation occurring near the GOE, we propose that ammonia oxidation likely occurred at the common ancestor of Gamma-AOB and Gammaproteobacterial methanotrophs, or the actinobacterial/verrucomicrobial methanotrophs which are known to have ammonia oxidation activities. It is also likely that nitrite was transported from the terrestrial habitats where ammonia oxidation by archaea took place. Further, we show that the Gamma-AOB predated the anaerobic ammonia-oxidizing (anammox) bacteria, implying that the emergence of anammox was constrained by the availability of dedicated ammonia oxidizers which produce nitrite to fuel anammox. Our work supports a new hypothesis that N redox cycle involving nitrogen oxides evolved rather late in the ocean.
Citation
Liao , T , Wang , S , Zhang , H , Stüeken , E E & Luo , H 2024 , ' Dating ammonia-oxidizing bacteria with abundant eukaryotic fossils ' , Molecular Biology and Evolution , vol. 41 , no. 5 , msae096 . https://doi.org/10.1093/molbev/msae096
Publication
Molecular Biology and Evolution
Status
Peer reviewed
ISSN
0737-4038Type
Journal article
Description
This work was supported by the Hong Kong Research Grants Council (RGC) General Research Fund (GRF) (14107823), the Natural Science Foundation of China (42293294), the Hong Kong Research Grants Council Area of Excellence Scheme (AoE/M-403/16), the Guangdong Basic and Applied Basic Research Foundation (2022A1515010844 to H.Z.), and the China Postdoctoral Science Foundation (2021M702296 to H.Z.).Collections
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