There are few measurements of nitrification in polar regions, yet geochemical evidence suggests that it is significant, and chemoautotrophy supported by has been suggested as an important contribution to prokaryotic production during the winter. This study reports seasonal ammonia oxidation (AO) rates, gene transcript abundance continental shelf waters west Antarctic Peninsula, where Thaumarchaeota strongly dominate populations ammonia-oxidizing organisms. Higher AO rates were observed late...

We sampled Thaumarchaeota populations in the northern Gulf of Mexico, including shelf waters under Mississippi River outflow plume that are subject to recurrent hypoxia. Data from this study allowed us to: 1) test hypothesis would be abundant region; 2) assess phylogenetic composition these for comparison with other regions; 3) compare efficacy quantitative PCR (qPCR) based on primers 16S rRNA genes (rrs) ammonia oxidation (amoA) and carbon fixation (accA, hcd) pathways; 4) distributions...

Urea nitrogen has been proposed to contribute significantly nitrification by marine thaumarchaeotes. These inferences are based on distributions of thaumarchaeote urease genes rather than activity measurements. We found that ammonia oxidation rates were always higher urea-derived N in samples from coastal Georgia, USA (means ± SEM: 382 35 versus 73 24 nmol L-1 d-1 , Mann-Whitney U-test p < 0.0001), and the South Atlantic Bight (20 8.8 2.2 1.7 = 0.026) but not Gulf Alaska (8.8 4.0 1.5 0.6, >...

Wetlands host ∼20% of terrestrial organic carbon and serve as a major sink for atmospheric carbon. Anoxic soils sediments accrue soil (SOC) partly by hampering the activity extracellular oxidative enzymes that break down phenolic polymers. Upon aeration, fungal-driven enzymatic depolymerization microbial respiration released monomers ensue. Redox-active metals can simultaneously catalyze abiotic nonspecific oxidation SOC, notable examples including Mn(III) or Fe(II) through Fenton-like,...

16S rRNA gene amplicons were pyrosequenced to assess bacterioplankton community composition, diversity, and phylogenetic structure for 17 stations in the northern Gulf of Mexico (nGoM) sampled March 2010. Statistical analyses showed that samples from depths ≤100 m differed distinctly deeper samples. SAR 11 α-Proteobacteria Bacteroidetes dominated communities at m, which characterized by high α-Proteobacteria/γ-Proteobacteria ratios (α/γ > 1.7). Thaumarchaeota, Firmicutes, δ-Proteobacteria...

Marine Thaumarchaeota were discovered over 20 years ago and although a few isolates from this group are now available for study, we do not yet understand the environmental controls on their growth distribution. Thaumarchaeotes oxidize ammonia to nitrite, mediating key step in global nitrogen cycle, it is estimated that about 20% of all prokaryotic cells ocean belong phylum. Despite almost ubiquitous distribution, marine rarely abundant open-ocean surface (<100 m) waters. We tested hypothesis...

Natural and anthropogenic activities introduce alkanes into marine systems where they are degraded by alkane hydroxylases expressed phylogenetically diverse bacteria. Partial sequences for alkB, one of the structural genes hydroxylase, have been used to assess composition alkane-degrading communities, determine their responses hydrocarbon inputs. We present here first spatially extensive analysis alkB in bacterioplankton northern Gulf Mexico (nGoM), a region that experiences numerous...

Abstract Trait‐based ecology, which focuses on using the traits of species and individuals to understand ecology (from populations ecosystems), is becoming an increasingly productive widely employed paradigm. To date, trait‐based approaches have been used study taxa from microbes megafauna in every major area aquatic yielding exciting results. However, this promising field faces a number significant obstacles, including: (1) identifying measuring ecologically relevant traits, (2) integrating...

Mid-summer peaks in the abundance of Thaumarchaeota and nitrite concentration observed on Georgia, USA, coast could result from situ activity or advection populations another source. We collected data distribution Thaumarchaeota, ammonia-oxidizing betaproteobacteria (AOB), Nitrospina, environmental variables rates ammonia oxidation during six cruises South Atlantic Bight (SAB) April to November 2014. These were used examine seasonality nitrification offshore waters test hypothesis that bloom...

Abstract Dissolved organic nitrogen (DON) can account for a large fraction of the dissolved (N) pool in ocean, but cycling marine DON is poorly understood. Recent discoveries that urea‐ and cyanate‐N be oxidized by some strains Thaumarchaeota suggest these abundant microbes may able to access oxidize pool. However, measurements oxidation N supplied as compounds are scarce. Here, we compare rates variety samples from Georgia coastal waters, where nitrifier communities numerically dominated...

Sediment interfaces in alluvial aquifers have a disproportionately large influence on biogeochemical activity and, therefore, groundwater quality. Previous work showed that exports from fine-grained, organic-rich zones sustain reducing conditions downstream coarse-grained beyond the of reduced aqueous products alone. Here, we show sustained anaerobic can be attributed to export organic carbon, including live microorganisms, fine-grained zones. We used dual-domain column system with...

ABSTRACT Riparian floodplains are important regions for biogeochemical cycling, including nitrogen. Here, we present MAGs from nitrifying microorganisms, ammonia‐oxidising archaea (AOA) and comammox bacteria Slate River (SR) floodplain sediments (Crested Butte, CO, US). Additionally, explore potential nitrite‐oxidising (NOB) the Nitrospirales . AOA diversity in SR is lower than observed other western US Nitrosotalea ‐like lineages such as genus TA‐20 dominant AOA. No (AOB) were recovered....

Coastal upwelling regions are hotspots of biological productivity, supporting diverse communities microbial life and metabolisms. Monterey Bay (MB), a coastal ocean embayment in central California, experiences seasonal cold, nutrient-rich waters that sustain episodes high phytoplankton production surface waters. While productivity is intimately linked to metabolisms Archaea Bacteria, comprehensive understanding the community MB missing thus far, particularly relation distinct hydrographic...

Abstract Scientists who are skilled in communication reap professional and personal rewards. Unfortunately, gaps exist fostering curricular extracurricular training science communication. We focus our article on opportunities for university‐ department‐level leadership to train new scientists communicate effectively. Our motivation is threefold: (1) key being competitive the increasingly diverse job market, (2) early career “jump‐starts” societal benefits, (3) authors represent a group of...

Abstract Nitrification plays a key role in marine ecosystems where Thaumarchaeota are thought to be responsible for most of the ammonia oxidation water column. Over 2‐yr, near‐monthly time series at two sites Monterey Bay we observed repeatable seasonal and depth‐based patterns ecotype abundance that highlighted clear delineation between populations shallow euphotic (&lt; 50 m) vs. deeper mesopelagic (60–500 depths. Euphotic depths show greater seasonality influence from light, while waters...

ABSTRACT We use metagenome-assembled genomes (MAGs) to understand single-carbon (C1) compound-cycling—particularly methane-cycling—microorganisms in montane riparian floodplain sediments. generated 1,233 MAGs (&gt;50% completeness and &lt;10% contamination) from 50- 150-cm depth below the sediment surface capturing transition between oxic, unsaturated sediments anoxic, saturated Slate River (SR) (Crested Butte, CO, USA). recovered of putative methanogens, methanotrophs, methylotrophs ( n =...

Riparian floodplains represent an interaction zone between the terrestrial subsurface and rivers, where regional groundwater flows, infiltration, evapotranspiration drive mixing of water import/export nutrients contaminants. These dynamics create seasonally transient redox conditions that biogeochemical transformations, which strongly modify quality. Microbial responses to changing hydrological are perhaps critical step connecting hydrology geochemical transformations quality, yet not well...

Ammonia-oxidizing archaea (AOA) of the phylum Thaumarchaeota are key players in nutrient cycling, yet large gaps remain our understanding their ecology and metabolism. Despite multiple lines evidence pointing to a central role for copper-containing nitrite reductase (NirK) AOA metabolism, thaumarchaeal nirK gene is rarely studied environment. In this study, we examine diversity marine pelagic environment, light previously described ecological patterns populations. Phylogenetic analyses show...