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This article explores the potential link between obesity and respiratory allergies. The study conducted on mice found that obesity exacerbates the allergic response, leading to heightened manifestations compared to lean mice. However, the researchers also discovered that oral tolerance induction can effectively attenuate the allergic response and lung inflammation in obese mice. The findings suggest that mucosal allergen-specific immunomodulation may function by reducing specific inflammatory markers and maintaining certain immune cells in the lungs. [Extracted from the article]

Depolymerization of high‐molecular weight organic nitrogen (N) represents the major bottleneck of soil N cycling and yet is poorly understood compared to the subsequent inorganic N processes. Given the importance of organic N cycling and the rise of global change, we investigated the responses of soil protein depolymerization and microbial amino acid consumption to increased temperature, elevated atmospheric CO2, and drought. The study was conducted in a global change facility in a managed montane grassland in Austria, where elevated CO2 (eCO2) and elevated temperature (eT) were stimulated for 4 years, and were combined with a drought event. Gross protein depolymerization and microbial amino acid consumption rates (alongside with gross organic N mineralization and nitrification) were measured using 15N isotope pool dilution techniques. Whereas eCO2 showed no individual effect, eT had distinct effects which were modulated by season, with a negative effect of eT on soil organic N process rates in spring, neutral effects in summer, and positive effects in fall. We attribute this to a combination of changes in substrate availability and seasonal temperature changes. Drought led to a doubling of organic N process rates, which returned to rates found under ambient conditions within 3 months after rewetting. Notably, we observed a shift in the control of soil protein depolymerization, from plant substrate controls under continuous environmental change drivers (eT and eCO2) to controls via microbial turnover and soil organic N availability under the pulse disturbance (drought). To the best of our knowledge, this is the first study which analyzed the individual versus combined effects of multiple global change factors and of seasonality on soil organic N processes and thereby strongly contributes to our understanding of terrestrial N cycling in a future world. [ABSTRACT FROM AUTHOR]

Soil microbial communities play a major role in driving elemental fluxes in terrestrialecosystems. Nitrogen (N) is a fundamental element for all living organisms and changes tothe N cycle can have dramatic consequences in terms of feedbacks to climate change. It istherefore pivotal to precisely assess the effects of future climatic conditions on the microbialcommunities controlling its cycling, in order to increase our ability to predict climate changeconsequences. Here we report a study on inorganic nitrogen transformation from amultifactorial Climate Change experiment (ClimGrass – Grassland Carbon and NutrientDynamics in a Changing Climate) in a managed montane grassland in the central AustrianAlps which aims to assess the individual and combined effects of warming, elevatedCO2 and drought. Samples were collected at peak growing season in July 2017from field plots subjected to either ambient climate or simulated future climateconditions (combined +3 ∘C and +300 ppm CO2) and drought in a full factorial design.Gross nitrification rates were measured by isotope pool dilution assays with the goalof linking them to the identity and abundance of different nitrifier groups. Fivefunctional genes responsible for both NH4+ and NO2- oxidation were quantified byqPCR at both DNA and cDNA levels (indicating presence and expression of eachgene). In addition, we sequenced the same set of functional genes (Illumina MiSeq)with the goal of assessing changes in nitrifier community composition induced byclimate change treatments. Our results demonstrate a strong effect of drought on thetranscription of ammonia monooxygenase subunit A (amoA) genes of comammox clade BNitrospira (comaB) and ammonia-oxidizing archaea (AOA), with gene copy numbersbeing significantly lower in drought treatments compared to the controls, whilecombined warming and elevated CO2 had no effect. Ammonia-oxidizing bacteria(AOB) and nitrite-oxidizing bacteria (NOB) were affected by the future climatetreatment only, suggesting shifts in functional microbial community composition.Additionally, the future climate treatment did not significantly affect inorganic N pools orprocess rates, whereas drought significantly increased NH4+ concentrations andgross nitrification rates. The positive relationship between NH4+ concentrations andgross nitrification rates under drought suggest that the nitrification process wasrather limited by substrate availability than by microbial activity. In conclusion thisstudy demonstrates that climate change affects the diversity and differential geneexpression of functional microbial communities responsible for inorganic N cycling, butthat gross nitrification process rates responded to different triggers than nitrifierabundance. [ABSTRACT FROM AUTHOR]

Ammonia-oxidising archaea and nitrite-oxidising bacteria are common members of marine sponge microbiomes. They derive energy for carbon fixation and growth from nitrification - the aerobic oxidation of ammonia to nitrite and further to nitrate - and are proposed to play essential roles in the carbon and nitrogen cycling of sponge holobionts. In this study, we characterise two novel nitrifying symbiont lineages, Candidatus Nitrosokoinonia and Candidatus Nitrosymbion in the marine sponge Coscinoderma matthewsi using a combination of molecular tools, in situ visualisation, and physiological rate measurements. Both represent a new genus in the ammonia-oxidising archaeal class Nitrososphaeria and the nitrite-oxidising bacterial order Nitrospirales, respectively. Furthermore, we show that larvae of this viviparous sponge are densely colonised by representatives of Ca. Nitrosokoinonia and Ca. Nitrosymbion indicating vertical transmission. In adults, the representatives of both symbiont genera are located extracellularly in the mesohyl. Comparative metagenome analyses and physiological data suggest that ammonia-oxidising archaeal symbionts of the genus Ca. Nitrosokoinonia strongly rely on endogenously produced nitrogenous compounds (i.e., ammonium, urea, nitriles/cyanides, and creatinine) rather than on exogenous ammonium sources taken up by the sponge. Additionally, the nitrite-oxidising bacterial symbionts of the genus Ca. Nitrosymbion may reciprocally support the ammonia-oxidisers with ammonia via the utilisation of sponge-derived urea and cyanate. Comparative analyses of published environmental 16S rRNA gene amplicon data revealed that Ca. Nitrosokoinonia and Ca. Nitrosymbion are widely distributed and predominantly associated with marine sponges and corals, suggesting a broad relevance of our findings., (© The Author(s) [2024]. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

Depolymerization of high-molecular weight organic nitrogen (N) represents the major bottleneck of soil N cycling and yet is poorly understood compared to the subsequent inorganic N processes. Given the importance of organic N cycling and the rise of global change, we investigated the responses of soil protein depolymerization and microbial amino acid consumption to increased temperature, elevated atmospheric CO 2 , and drought. The study was conducted in a global change facility in a managed montane grassland in Austria, where elevated CO 2 (eCO 2 ) and elevated temperature (eT) were stimulated for 4 years, and were combined with a drought event. Gross protein depolymerization and microbial amino acid consumption rates (alongside with gross organic N mineralization and nitrification) were measured using 15 N isotope pool dilution techniques. Whereas eCO 2  showed no individual effect, eT had distinct effects which were modulated by season, with a negative effect of eT on soil organic N process rates in spring, neutral effects in summer, and positive effects in fall. We attribute this to a combination of changes in substrate availability and seasonal temperature changes. Drought led to a doubling of organic N process rates, which returned to rates found under ambient conditions within 3 months after rewetting. Notably, we observed a shift in the control of soil protein depolymerization, from plant substrate controls under continuous environmental change drivers (eT and eCO 2 ) to controls via microbial turnover and soil organic N availability under the pulse disturbance (drought). To the best of our knowledge, this is the first study which analyzed the individual versus combined effects of multiple global change factors and of seasonality on soil organic N processes and thereby strongly contributes to our understanding of terrestrial N cycling in a future world., (© 2021 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Nitrification is a fundamental process in terrestrial nitrogen cycling. However, detailed information on how climate change affects the structure of nitrifier communities is lacking, specifically from experiments in which multiple climate change factors are manipulated simultaneously. Consequently, our ability to predict how soil nitrogen (N) cycling will change in a future climate is limited. We conducted a field experiment in a managed grassland and simultaneously tested the effects of elevated atmospheric CO 2 , temperature, and drought on the abundance of active ammonia-oxidizing bacteria (AOB) and archaea (AOA), comammox (CMX) Nitrospira, and nitrite-oxidizing bacteria (NOB), and on gross mineralization and nitrification rates. We found that N transformation processes, as well as gene and transcript abundances, and nitrifier community composition were remarkably resistant to individual and interactive effects of elevated CO 2 and temperature. During drought however, process rates were increased or at least maintained. At the same time, the abundance of active AOB increased probably due to higher NH 4 + availability. Both, AOA and comammox Nitrospira decreased in response to drought and the active community composition of AOA and NOB was also significantly affected. In summary, our findings suggest that warming and elevated CO 2 have only minor effects on nitrifier communities and soil biogeochemical variables in managed grasslands, whereas drought favors AOB and increases nitrification rates. This highlights the overriding importance of drought as a global change driver impacting on soil microbial community structure and its consequences for N cycling.