Dataset Information

Differential contribution of nitrifying prokaryotes to nitrification in groundwater

ABSTRACT: The ecophysiology of complete ammonia oxidizing Nitrospira (CMX) and their widespread occurrence in groundwater suggests that CMX bacteria have a competitive advantage over ammonia-oxidizing bacteria (AOB) and archaea (AOA) in these environments. However, the relevance of their activity from the ecosystem-level process perspective has remained unclear. We investigated oligotrophic carbonate rock aquifers as a model system to assess the contribution of CMX, AOA and AOB to nitrification and to identify the environmental drivers of their niche differentiation at different levels of ammonium and oxygen. CMX accounted for up to 95% of the ammonia oxidizer communities. Nitrification rates were positively correlated to CMX clade A-associated phylotypes and AOB affiliated with Nitrosomonas ureae. Surprisingly, short-term incubations amended with the nitrification inhibitors allylthiourea and chlorate suggested that AOB contributed more than 90% to overall ammonia oxidation, while metaproteomics analysis confirmed an active role of CMX in both ammonia and nitrite oxidation. Ecophysiological niche differentiation of CMX clades A and B, AOA and AOB was linked to their requirements for ammonium, oxygen tolerance, and metabolic versatility. Our results demonstrate that despite numerical predominance of CMX, the first step of nitrification in oligotrophic groundwater is primarily governed by AOB. Higher growth yields at lower NH4+ turnover rates and energy derived from nitrite oxidation most likely enable CMX to maintain consistently high populations. Activity measurements combined with differential inhibition allowed a refined understanding of ammonia oxidizer coexistence, competition and cooperation beyond the insights from molecular data alone.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Escherichia Coli

SUBMITTER: Nico Jehmlich

LAB HEAD: Nico Jehmlich

PROVIDER: PXD039573 | Pride | 2023-10-24

REPOSITORIES: Pride

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Dataset's files

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			Action	DRS
	20200201_NJ_Martin_Taubert_ADMG_10.msf	Msf
	20200201_NJ_Martin_Taubert_ADMG_10.raw	Raw
	20200201_NJ_Martin_Taubert_ADMG_12.msf	Msf
	20200201_NJ_Martin_Taubert_ADMG_12.raw	Raw
	20200201_NJ_Martin_Taubert_ADMG_22.msf	Msf

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Differential contribution of nitrifying prokaryotes to groundwater nitrification.

Krüger Markus M Chaudhari Narendrakumar N Thamdrup Bo B Overholt Will A WA Bristow Laura A LA Taubert Martin M Küsel Kirsten K Jehmlich Nico N von Bergen Martin M Herrmann Martina M

The ISME journal 20230708 10

The ecophysiology of complete ammonia-oxidizing bacteria (CMX) of the genus Nitrospira and their widespread occurrence in groundwater suggests that CMX bacteria have a competitive advantage over ammonia-oxidizing bacteria (AOB) and archaea (AOA) in these environments. However, the specific contribution of their activity to nitrification processes has remained unclear. We aimed to disentangle the contribution of CMX, AOA and AOB to nitrification and to identify the environmental drivers of their ...[more]

PMID: 37422599

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