Hikarchaeia demonstrate an intermediate stage in the methanogen-to-halophile transition
Martijn, J.; Schön, M.E.; Lind, A.E.; Vosseberg, J.; Williams, T.A.; Spang, A.; Ettema, T.J.G. (2020). Hikarchaeia demonstrate an intermediate stage in the methanogen-to-halophile transition. Nature Comm. 11: 5490. https://doi.org/10.1038/s41467-020-19200-2
Additional data:
In: Nature Communications. Nature Publishing Group: London. ISSN 2041-1723; e-ISSN 2041-1723, more
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Authors | | Top |
- Martijn, J.
- Schön, M.E.
- Lind, A.E.
- Vosseberg, J.
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- Williams, T.A.
- Spang, A., more
- Ettema, T.J.G.
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Abstract |
Halobacteria (henceforth: Haloarchaea) are predominantly aerobic halophiles that are thought to have evolved from anaerobic methanogens. This remarkable transformation most likely involved an extensive influx of bacterial genes. Whether it entailed a single massive transfer event or a gradual stream of transfers remains a matter of debate. To address this, genomes that descend from methanogen-to-halophile intermediates are necessary. Here, we present five such near-complete genomes of Marine Group IV archaea (Hikarchaeia), the closest known relatives of Haloarchaea. Their inclusion in gene tree-aware ancestral reconstructions reveals an intermediate stage that had already lost a large number of genes, including nearly all of those involved in methanogenesis and the Wood-Ljungdahl pathway. In contrast, the last Haloarchaea common ancestor gained a large number of genes and expanded its aerobic respiration and salt/UV resistance gene repertoire. Our results suggest that complex and gradual patterns of gain and loss shaped the methanogen-to-halophile transition. |
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