Publikation

Zurück zur Übersicht

Crenotrhix are major methane consumers in stratified lakes

Publikationsart Peer-reviewed
Publikationsform Originalbeitrag (peer-reviewed)
Autor/in Oswald Kirsten, Graf Jon, Littmann Sten, Tienken Daniela, Brand Andreas, Wehrli Bernhard, Abertsen Mads, Daims Holger, Wagner Michael,
Projekt Factors governing methane oxidation pathways at redox boundaries in lakes
Alle Daten anzeigen

Originalbeitrag (peer-reviewed)

Zeitschrift The ISME Journal
Titel der Proceedings The ISME Journal
DOI 10.1038/ismej.2017.77

Open Access

Abstract

Methane-oxidizing bacteria represent a major biological sink for methane and are thus Earth’s natural protection against this potent greenhouse gas. Here we show that in two stratified freshwater lakes a substantial part of upward-diffusing methane was oxidized by filamentous gamma-proteobacteria related to Crenothrix polyspora. These filamentous bacteria have been known as contaminants of drinking water supplies since 1870, but their role in the environmental methane removal has remained unclear. While oxidizing methane, these organisms were assigned an ‘unusual’ methane monooxygenase (MMO), which was only distantly related to ‘classical’ MMO of gamma-proteobacterial methanotrophs. We now correct this assignment and show that Crenothrix encode a typical gamma-proteobacterial PmoA. Stable isotope labeling in combination swith single-cell imaging mass spectrometry revealed methane-dependent growth of the lacustrine Crenothrix with oxygen as well as under oxygen-deficient conditions. Crenothrix genomes encoded pathways for the respiration of oxygen as well as for the reduction of nitrate to N2O. The observed abundance and planktonic growth of Crenothrix suggest that these methanotrophs can act as a relevant biological sink for methane in stratified lakes and should be considered in the context of environmental removal of methane. Hide Details
-