Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1020623 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Acididesulfobacillus acetoxydans is an acidophilic sulfate reducer that can dissimilatory reduce nitrate to ammonia (DNRA). However, no known nitrite reductase is encoded. This study was performed to investigate how A. acetoxydans reduces nitrate to nitrite and elucidated a novel DNRA mechanism and potential nitrosative stress resistance mechanisms in acidophiles.
2024-01-26 | PXD045135 | Pride
Project description:Nitrification, the oxidation of ammonia via nitrite to nitrate, has always been considered to be a two-step process catalysed by chemolithoautotrophic microorganisms oxidizing either ammonia or nitrite. No known nitrifier carries out both steps, although complete nitrification should be energetically advantageous. This functional separation has puzzled microbiologists for a century. Here we report on the discovery and cultivation of a completely nitrifying bacterium from the genus Nitrospira, a globally distributed group of nitrite oxidizers. The genome of this chemolithoautotrophic organism encodes the pathways both for ammonia and nitrite oxidation, which are concomitantly activated during growth by ammonia oxidation to nitrate. Genes affiliated with the phylogenetically distinct ammonia monooxygenase and hydroxylamine dehydrogenase genes of Nitrospira are present in many environments and were retrieved on Nitrospira contigs in new metagenomes from engineered systems. These findings fundamentally change our picture of nitrification and point to completely nitrifying Nitrospira as key components of nitrogen-cycling microbial communities.
2019-03-15 | PXD013103 | Pride
Project description:Transcriptional profiling of marine ammonia oxidizing archaea Nitrosopumilus maritimus cells comparing exponential phase control cells with cells under 24 hours starvation and with cells under recovery after 24 hours starvation. Goal was to determine the effects of global transcriptional responses of N. maritimus cells under ammonia starvation and recovery conditions.
2017-11-01 | GSE103848 | GEO
Project description: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.
2023-10-24 | PXD039573 | Pride
Project description:Marine sponges represent one of the few eukaryotic groups that ubiquitously harbor symbiotic members of the Thaumarchaeota, which are important chemoautotrophic ammonia-oxidizers in many environments. However in most studies, direct demonstration of ammonia-oxidation by these archaea within sponges is lacking, and little is known about sponge-specific adaptations of archaeal ammonia oxidizers (AOA). In this study, we characterized the thaumarchaeal symbiont of the marine sponge Ianthella basta using metaproteogenomics, fluorescence in situ hybridization, qPCR and direct isotope-based functional assays. We demonstrate that the I. basta symbiont is not closely related to other genomically sequenced sponge AOA and is a member of a new genus. “Candidatus Nitrosospongia bastadiensis” is an abundant symbiont that is solely responsible for nitrite formation from ammonia in I. basta that surprisingly does not harbor nitrite-oxidizing microbes. Consistently, Ca N. bastadiensis encodes and expresses the genetic repertoire required for chemolithoautotrophic ammonia oxidation. Furthermore, we show that this AOA is equipped with an expanded set of extracellular subtilisin-like proteases, a metalloprotease unique among archaea, as well as a putative branched-chain amino acid ABC transporter. This repertoire is strongly indicative of a mixotrophic lifestyle and is (with slight variations) also found in other sponge-associated, but not in free-living AOA. We predict that this feature as well as an expanded and unique set of secreted serpins (protease inhibitors), a unique array of eukaryotic-like proteins, and a DNA-phosporothioation system likely involved in defense against foreign DNA, represent important adaptations of AOA to life within these ancient filter-feeding animals.
2019-11-13 | PXD012484 | Pride
Project description:Acidophilic iron-oxidizing bacterium
| PRJNA35067 | ENA