Coupling methane oxidation and N₂ fixation under methanogenic conditions in contrasting environments

verfasst von

Yongliang Mo, Jiwei Li, Xiaotong Peng, Adrian Ho, Zhongjun Jia

Abstract

Microbial methane oxidation under widespread suboxic environment is crucial for understanding methane emission. However, the role of aerobic methanotrophs in mediating methane oxidation and nitrogen fixation is less understood in oxygen-limiting environments. In this study, we identified diazotrophic methanotrophs under oxygen-limited conditions (initial O₂ of 6–8 μM) in two contrasting habitats (paddy soil and marine sediment) using DNA-based stable isotope probing combined with amplicon sequencing. Consistently, we documented significant ¹³CH₄ oxidation and ¹⁵N₂ fixation after 740 days of suboxic isotope labeling. Sequencing analysis revealed the predominance of Methylobacter–affiliated aerobic methanotrophs in the ¹³C-labeled DNA fractions. These Methylobacter-like OTUs accounted for 97.86 % in paddy soil and 99.49 % in marine sediment of the total pmoA gene sequences; while relative abundances for the nifH gene sequences were 91.59 % in paddy soil and 99.49 % in marine sediment. Taken together, our analyses revealed that Methylobacter is responsible for methane oxidation and nitrogen fixation under oxygen limitation in both habitats, demonstrating convergent emergence of this aerobic methanotroph under oxygen deficiency.

Organisationseinheit(en)

Institut für Mikrobiologie

Externe Organisation(en)

Chinese Academy of Sciences (CAS)
China West Normal University
Institute of Deep-Sea Science and Engineering

Typ

Artikel

Journal

European journal of soil biology

Band

123

Anzahl der Seiten

4

ISSN

1164-5563

Publikationsdatum

12.2024

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Mikrobiologie, Bodenkunde, Insektenkunde

Ziele für nachhaltige Entwicklung

SDG 14 – Lebensraum Wasser

Elektronische Version(en)

https://doi.org/10.1016/j.ejsobi.2024.103693 (Zugang: Geschlossen)