Osmoregulation in freshwater anaerobic methane-oxidizing archaea under salt stress

Climate change–driven sea level rise threatens freshwater ecosystems and elicits salinity stress in microbiomes. Methane emissions in these systems are largely mitigated by methane-oxidizing microorganisms. Here, we characterized the physiological and metabolic response of freshwater methanotrophic...

Full description

Bibliographic Details
Authors: Echeveste Medrano, Maider, Leu, Andy, Pabst, Martin, Lin, Yuemei, McIlroy, Simon, Tyson, Gene, van Ede, Jitske, Sánchez Andrea, Irene, Jetten, Mike, Jansen, Robert, Welte, Cornelia
Format: article
Publication Date:2024
Country:España
Institution:IE
Repository:Repositorio IE
OAI Identifier:oai:repositorio.ie.edu:20.500.14417/4215
Online Access:https://doi.org/10.1093/ismejo/wrae137
https://hdl.handle.net/20.500.14417/4215
https://academic.oup.com/ismej/article/18/1/wrae137/7717430
Access Level:Open access
Keyword:ODS 13 - Acción por el clima
compatible solutes
methanotroph
salinity adaptation
ANME
metabolomics
“Ca. Methanoperedens”
Description
Summary:Climate change–driven sea level rise threatens freshwater ecosystems and elicits salinity stress in microbiomes. Methane emissions in these systems are largely mitigated by methane-oxidizing microorganisms. Here, we characterized the physiological and metabolic response of freshwater methanotrophic archaea to salt stress. In our microcosm experiments, inhibition of methanotrophic archaea started at 1%. However, during gradual increase of salt up to 3% in a reactor over 12 weeks, the culture continued to oxidize methane. Using gene expression profiles and metabolomics, we identified a pathway for salt-stress response that produces the osmolyte of anaerobic methanotrophic archaea: N(ε)-acetyl-β-L-lysine. An extensive phylogenomic analysis on N(ε)-acetyl-β-L-lysine-producing enzymes revealed that they are widespread across both bacteria and archaea, indicating a potential horizontal gene transfer and a link to BORG extrachromosomal elements. Physicochemical analysis of bioreactor biomass further indicated the presence of sialic acids and the consumption of intracellular polyhydroxyalkanoates in anaerobic methanotrophs during salt stress.