The expansion of fungal organisms in environmental biotechnology.

Fungal organisms hold vital roles in ecosystem processes. Despite their intricate entanglement with most life on earth and their powerful metabolic capacities, they remain under-represented in environmental biotechnology. The interest in applying fungal biotechnologies to different environments is growing, as light is shed on their versatile potential.

Microbe-cellulose hydrogels as a model system for particulate carbon degradation in soil aggregates.

Particulate carbon (C) degradation in soils is a critical process in the global C cycle governing greenhouse gas fluxes and C storage. Millimeter-scale soil aggregates impose strong controls on particulate C degradation by inducing chemical gradients of e.g.

Impact of aerobic granular sludge sizes and dissolved oxygen concentration on greenhouse gas NO emission.

Aerobic granular sludge (AGS) at wastewater treatment plants (WWTPs) are known to produce nitrous oxide (NO), a greenhouse gas which has a ∼300 times higher global warming potential than carbon dioxide. In this research, we studied NO emissions from different sizes of AGS developed at a dissolved oxygen (DO) level of 2 mgO/L while exposing them to disturbances at various DO concentrations ranging from 1 to 4 mgO/L. Five different AGS size classes were studied: 212-600 µm, 600-1000 µm, 1000-1400 µm, 1400-2000 µm, and > 2000 µm.

Integrating socio-economic vulnerability factors improves neighborhood-scale wastewater-based epidemiology for public health applications.

Wastewater Based Epidemiology (WBE) of COVID-19 is a low-cost, non-invasive, and inclusive early warning tool for disease spread. Previously studied WBE focused on sampling at wastewater treatment plant scale, limiting the level at which demographic and geographic variations in disease dynamics can be incorporated into the analysis of certain neighborhoods. This study demonstrates the integration of demographic mapping to improve the WBE of COVID-19 and associated post-COVID disease prediction (here kidney disease) at the neighborhood level using machine learning.

Co-immobilization of AOA strains with anammox bacteria in three different synthetic bio-granules maintained under two substrate-level conditions.

Hydrogel encapsulation of ammonium oxidizing archaea (AOA) along with anammox bacteria holds potential to enable mainstream partial nitritation (PN)-anammox process attributing to AOA's high affinity to ammonia and oxygen. This study explored the growth of AOA and anammox in hydrogel-based synthetic biogranules by testing two AOA strains, three types of hydrogel beads and two substrate levels, to identify the optimal combination favoring the concomitant growth of AOA and anammox. The AOA Nitrososphaera viennensis (AOA-NV) exhibited higher abundance (10 AOA/16S) than the AOA-DW (10 AOA/16S) during the entire experimental period.

Goethite Formed in the Periplasmic Space of sp. JM-7 during Fe Cycling Enhances Its Denitrification in Water.

Denitrification-driven Fe(II) oxidation is an important microbial metabolism that connects iron and nitrogen cycling in the environment. The formation of Fe(III) minerals in the periplasmic space has a significant effect on microbial metabolism and electron transfer, but direct evidence of iron ions entering the periplasm and resulting in periplasmic mineral precipitation and electron conduction properties has yet to be conclusively determined. Here, we investigated the pathways and amounts of iron, with different valence states and morphologies, entering the periplasmic space of the denitrifier sp.

Biological and physical selectors for mobile biofilms, aerobic granules, and densified-biological flocs in continuously flowing wastewater treatment processes: A state-of-the-art review.

There have been significant advances in the use of biological and physical selectors for the intensification of continuously flowing biological wastewater treatment (WWT) processes. Biological selection allows for the development of large biological aggregates (e.g.

Cross-Feedings, Competition, and Positive and Negative Synergies in a Four-Species Synthetic Community for Anaerobic Degradation of Cellulose to Methane.

Complex interactions exist among microorganisms in a community to carry out ecological processes and adapt to changing environments. Here, we constructed a quad-culture consisting of a cellulolytic bacterium (Ruminiclostridium cellulolyticum), a hydrogenotrophic methanogen (Methanospirillum hungatei), an acetoclastic methanogen (Methanosaeta concilii), and a sulfate-reducing bacterium (Desulfovibrio vulgaris). The four microorganisms in the quad-culture cooperated via cross-feeding to produce methane using cellulose as the only carbon source and electron donor.

Wastewater surveillance of SARS-CoV-2 at intra-city level demonstrated high resolution in tracking COVID-19 and calibration using chemical indicators.

Wastewater-based epidemiology has proven to be a supportive tool to better comprehend the dynamics of the COVID-19 pandemic. As the disease moves into endemic stage, the surveillance at wastewater sub-catchments such as pump station and manholes is providing a novel mechanism to examine the reemergence and to take measures that can prevent the spread. However, there is still a lack of understanding when it comes to wastewater-based epidemiology implementation at the smaller intra-city level for better granularity in data, and dilution effect of rain precipitation at pump stations.

Photoinhibition of comammox reaction in in a dose- and wavelength-dependent manner.

Apparent contribution of complete ammonia-oxidizing organisms (comammox) to the global nitrogen cycle highlights the necessity for understanding niche differentiation of comammox bacteria among other ammonia oxidizers. While the high affinity for ammonia of the comammox species suggests their niche partitioning is expected to be centered in oligotrophic environments, their absence in nutrient-depleted environments (such as the oceans) suggests that other (abiotic) factors might control their distribution and spatial localization within microbial communities. Many ammonia- and nitrite-oxidizing organisms are sensitive to light; however, the photosensitivity of comammox has not been explored.

Case Study: Impact of Diurnal Variations and Stormwater Dilution on SARS-CoV-2 RNA Signal Intensity at Neighborhood Scale Wastewater Pumping Stations.

Wastewater based epidemiology (WBE) has emerged as a tool to track the spread of SARS-CoV-2. However, sampling at wastewater treatment plants (WWTPs) cannot identify transmission hotspots within a city. Here, we sought to understand the diurnal variations (24 h) in SARS-CoV-2 RNA titers at the neighborhood level, using pump stations that serve vulnerable communities (e.

Application of pyritic sludge with an anaerobic granule consortium for nitrate removal in low carbon systems.

Granules recovered from a highly reduced anaerobic digester were capable of active nitrogen removal in the absence of exogenous electron donors, averaging 0.25 mg mgNO-N /gVSS/d over 546 days of operation. Electron mass balance indicated that about half the influent nitrate was converted to ammonia via DNRA and another half denitrified.

Sustained nitrogen loss in a symbiotic association of Comammox Nitrospira and Anammox bacteria.

The discovery of anaerobic ammonia-oxidizing bacteria (Anammox) and, more recently, aerobic bacteria common in many natural and engineered systems that oxidize ammonia completely to nitrate (Comammox) have significantly altered our understanding of the global nitrogen cycle. A high affinity for ammonia (K ≈ 63nM) and oxygen place Comammox Nitrospira inopinata, the first described isolate, in the same trophic category as organisms such as some ammonia-oxidizing archaea. However, N.

Application of aerobic kenaf granules for biological nutrient removal in a full-scale continuous flow activated sludge system.

Aerobic granular sludge (AGS) is a biofilm technology that offers more treatment capacity in comparison to activated sludge. The integration of AGS into existing continuous-flow activated sludge systems is of great interest as process intensification can be achieved without the use of plastic-based biofilm carriers. Such integration should allow good separation of granules/flocs and ideally with minor retrofitting, making it an ongoing challenge.

Elucidating the Competition between Heterotrophic Denitrification and DNRA Using the Resource-Ratio Theory.

Heterotrophic denitrification and dissimilatory nitrate reduction to ammonium (DNRA) are two microbial processes competing for two shared resources, namely, nitrate and organic carbon (COD). Their competition has great implications for nitrogen loss, conservation, and greenhouse gas emissions. Nevertheless, a comprehensive and mechanistic understanding of the governing factors for this competition is still lacking.

Effective nitrogen removal from ammonium-depleted wastewater by partial nitritation and anammox immobilized in granular and thin layer gel carriers.

This study investigates the effect of physicochemical conditions on the partial nitritation and anammox treatment by immobilized ammonia oxidizers under ammonium-deplete conditions. The impact of oxygen and temperature was studied by measuring the activity of immobilized aerobic and anaerobic ammonia-oxidizing organisms (Ammonia-oxidizing bacteria (AOB) and archaea (AOA), and Anammox bacteria) embedded in polyvinyl alcohol - sodium alginate (PVA-SA) beads and in thin layer poly-ethylene glycol hydrogels. Beads and flat hydrogels were incubated in a fluidized bed reactor (FBR) and in two flow cells, respectively.

Correlating sludge constituents with digester foaming risk using sludge foam potential and rheology.

Foam potential and viscometer ramp tests (VRTs) were conducted for three municipal wastewater treatment plants to determine if these methods can relate to mechanisms of foaming to physical and biological constituents in sludge. At all plants, digester volatile solids (VS) concentration correlated (R > 0.41) with increases in plastic viscosity, a VRT parameter corresponding to foaming risk.

A Complex Interplay between Nitric Oxide, Quorum Sensing, and the Unique Secondary Metabolite Tundrenone Constitutes the Hypoxia Response in .

species, members of the , have recently emerged as some of the globally widespread, cosmopolitan species that play a key role in the environmental consumption of methane across gradients of dioxygen tensions. In this work, we approached the question of how copes with hypoxia, via laboratory manipulation. Through comparative transcriptomics of cultures grown under high dioxygen partial pressure versus cultures exposed to hypoxia, we identified a gene cluster encoding a hybrid cluster protein along with sensing and regulatory functions.

Reducing Cost and Environmental Impact of Wastewater Treatment with Denitrifying Methanotrophs, Anammox, and Mainstream Anaerobic Treatment.

In water resource recovery facilities, sidestream biological nitrogen removal via anaerobic ammonium oxidation (anammox) is more energy and cost efficient than conventional nitrification-denitrification. However, under mainstream conditions, nitrite oxidizing bacteria (NOB) out-select anammox bacteria for nitrite produced by ammonium oxidizing bacteria (AOB). Therefore, nitrite production is the bottleneck in mainstream anammox nitrogen removal.

Kinetic implication of moving warm side-stream Anaerobic ammonium oxidizing bacteria to cold mainstream wastewater.

Decreased activity of Anaerobic ammonia oxidation (Anammox) at low temperatures is widely reported and one of the key challenges to applying Anammox to mainstream wastewater treatment. In this work, we systematically measured Anammox across a range of temperatures for biomass taken from a side-stream (25-30 °C) Anammox system. Using the Cardinal temperature model with inflection (CTMI) and parameters T = 10 °C, T = 31 °C, T = 40 °C, and µ = 0.

New directions in biological nitrogen removal and recovery from wastewater.

This review summarizes strategies for biological nitrogen removal (BNR) and recovery from wastewater. The most commonly used BNR technology nitrification/denitrification is also the most energy intensive, even though there are lower energy options, including nitritation/denitritation and more efficient partial nitritation/Anammox; the latter is well demonstrated for side-stream treatment and progressing toward mainstream applications. Nitrogen recovery can be done through cell assimilation with phototrophs, but bottlenecks with solids separation and space requirements limit applications to tertiary treatment.

Perchlorate bioreduction linked to methane oxidation in a membrane biofilm reactor: Performance and microbial community structure.

Perchlorate bioreduction coupled to methane oxidation was successfully achieved without the addition of nitrate or nitrite in a membrane biofilm reactor (MBfR) inoculated with a mixture of freshwater sediments and anaerobic digester sludge as well as return activated sludge. The reactor was operated at different methane pressures (60, 40 and 20 Kpa) and influent perchlorate concentrations (1, 5 and 10 mg/L) to evaluate the biochemical process of perchlorate bioreduction coupled to methane oxidation. Perchlorate was completely reduced with a higher removal flux of 92.

Integration of methane removal in aerobic anammox-based granular sludge reactors.

Combined partial nitritation-anaerobic ammonium oxidation (anammox) processes have been widely applied for nitrogen removal from anaerobic digestion reject water. However, such streams also contain dissolved methane that can escape to the atmosphere, hence contributing to global warming. This study investigates the possibility of integrating methane removal in aerobic anammox-based granular sludge reactors, through modelling and simulation.

Evaluating the potential for dissimilatory nitrate reduction by anammox bacteria for municipal wastewater treatment.

Anammox bacteria can perform dissimilatory nitrate reduction to ammonium (DNRA) with nitrite as intermediate coupled to the oxidation of volatile fatty acids (VFA). Batch tests with enriched anammox and a co-culture of anammox and heterotrophic bacteria showed the capacity of Candidatus 'Brocadia fulgida' to perform the DNRA coupled to the anammox reaction (DNRA-anammox) at a high rate although the culture was not previously adapted to VFA. From thermodynamic calculations it could be stated that low COD/N influent ratios favour the DNRA-anammox transformation over heterotrophic conversions since more free energy is gained.

Influence of process dynamics on the microbial diversity in a nitrifying biofilm reactor: Correlation analysis and simulation study.

For engineers, it is interesting to gain insight in the effect of control strategies on microbial communities, on their turn influencing the process behavior and its stability. This contribution assesses the influence of process dynamics on the microbial community in a biofilm reactor for nitrogen removal, which was controlled according to several strategies aiming at nitrite accumulation. The process dataset, combining conventional chemical and physical data with molecular information, was analyzed through a correlation analysis and in a simulation study.