Environmental Pollution

Exposure to higher levels of ambient air pollution during pregnancy has been linked to multiple adverse pregnancy outcomes. However, studies on acute exposures and reduced gestation length have reported inconsistent findings. This project aims to examine the acute association between ambient air pollution and preterm (28-36 gestational weeks) or early-term (37-38 gestational weeks) births. Daily concentrations of 12 air pollutants, based on bias-corrected numerical model outputs, were linked to vital records of singleton live preterm and early-term births from 2005-2017 in California, Florida, Georgia, Kansas, Nevada, New Jersey, North Carolina (2005-2015), and Oregon. Under a time-stratified case-crossover design, odds ratios (OR) were estimated via conditional logistic regression with adjustment for risks among ongoing pregnancies, meteorology, time trends and federal holidays. We estimated cumulative associations up to a 6-day lag using distributed lag models. Risk estimates per interquartile range (IQR) increase in exposure were pooled across states using inverse-variance weighting. Our study included 1,085,162 preterm and 3,901,185 early-term births. We observed positive associations between 0-2 day cumulate exposure to several air pollutants and early-term births, including NO2 (OR: 1.0023, 95% CI:1.0010, 1.0037 per 7.1 g/m3 increase), PM2.5 (OR=1.0022, 95% CI: 1.006, 1.0038 per 4.6 g/m3 increase), PM2.5 organic carbon (OR= 1.0026, 95% CI: 1.0013, 1.0039 per 1.7 g/m3 increase) and PM2.5 elemental carbon (OR=1.0025, 95% CI: 1.0014, 1.0035 per 0.26 g/m3 increase). Associations with preterm birth were mostly null. In conclusion, we found positive associations between short-term air pollution exposure, including PM and major PM2.5 components, and risks of early-term birth.

Metals and per- and polyfluoroalkyl substances (PFAS) represent a significant environmental concern, yet their association with epigenetic age acceleration (EAA) remain largely understudied in marine mammals. Here, associations between EAA in common dolphins (Delphinus delphis) and life history (sex and sexual maturity), trace metals, and PFAS were investigated. EAA was calculated as the residual in the regression of epigenetic age vs chronological age, hence providing a direct measure of the deviation of the epigenetic age of an organism (positive or negative) by comparison with expectation, given their actual chronological age. Sixteen trace elements were quantified in hepatic and renal tissues (n = 53). In addition, 28 PFAS were quantified in hepatic tissue (n = 58). Associations between EAA and explanatory variables were assessed using regression-based and multivariate modelling approaches (linear models and canonical analysis of principal coordinates). No effect of sex was observed, although sexual maturity did significantly increase EAA. Exposure to metals was significantly associated with EAA, explaining 55.4% of the variation, with hepatic metals (Se, Zn, Cu, Al, Mn) driving this relationship. Although EAA was not significantly related to the total PFAS exposure overall, a subset of PFAS variables (PFBA, PFDA, PFHxS-B, PFNA) showed significant association with EAA after adjusting for sex and sexual maturity. Together, these subsets of metal and PFAS variables, in addition to the selenium-to-mercury (Se:Hg) molar ratio, explained 66.7% of the variation in EAA. Our results identify sexual maturity and specific contaminant mixtures as key potential drivers of EAA in common dolphins, highlighting the possible use of EAA as a biomarker of environmental and physiological stress in marine mammals.

Compact poultry raising has turned poultry litter into an environmental problem, as it may all be packed with heavy metals and drug-resistant germs. Of all the metals, chromium contamination not only disturbs the general environment but is also a source of concern for public health. Poultry litters were taken from 14 farms in different places, and the bacteria characters from different places were tested for their capacity to tolerate Cr(VI). A total of 31 bacterial isolates were initially screened, and three of them (AH-2, AZ-1, and AMF-3) appeared to be very resistant to chromium. The isolates were able to survive at the highest concentration, 800 mg/L of the Cr(VI); however, AH-2 was the most resistant one (MIC: 900 mg/L; MBC: 1000 mg/L). Chromium reduction tests showed that AMF-3 at high concentration showed the maximum chromium reduction, while AH-2 achieved higher chromium reduction at medium concentration. Phenotypic and biochemical analysis showed that the isolates were Staphylococcus spp., which was confirmed by 16S rRNA gene sequencing as S. cohnii, S. saprophyticus, and S. gallinarum. Moreover, chromium was detected at higher levels in poultry litter compared to the feed, with the highest accumulation in AZ farm litter (4464.0 {micro}g/kg). The highlighting feature of our article is the presence of chromium-tolerant and reducing bacteria in poultry environments. Besides that, the level of chromium in poultry litter is really high, and it points to the need for better waste management.

ABTRACT Background Children from low- and middle-income countries are particularly vulnerable to air pollution, a major environmental health risk, due to the immaturity of their lungs and their proximity to sources of household pollution. This study aimed to investigated the effect of exposure to biomass combustion through domestic and maternal occupational activities on respiratory health of children living in disadvantaged urban areas of Abidjan, Cote dIvoire. Methods Between February and December 2023, we conducted a cross-sectional observational study among children <16 years from households of women using biomass fuel for cooking (Group (G) 1), engaged in occupational fish smoking activities (G2), or primarily using gas for domestic cooking (G3). We assessed reported respiratory symptoms through standardized questionnaires and the presence of lung function impairments (LFI) though pulmonary function tests (spirometry and Rint). We assessed the association between study groups and key covariates with respiratory symptoms and LFI using mixed-effects regression models. Results Of 210 children enrolled - 119 (56.8%) female, median age 9 (6-12) years, 82 (39.0%) in G1, 47 (22.4%) in G2, and 81 (38.6%) in G3 - 15 (7.1%) reported wheezing in the last 12 months, 82 (39.0%) reported dry cough at night, 9 (4.9%) presented with dyspnea and 5 (2.7%) had chest pain on clinical examination, for an overall proportion of children with reported respiratory symptoms of 43.8% (92/210). Of 176 children who underwent pulmonary function testing, 59 (33.5%) had LFI detected, including 34 (45.9%) in G1, 8 (22.2%) in G2, and 17 (25.8%) in G3 (p = 0.011). Study group was associated with respiratory symptoms (G1 vs G3; aOR 3.82, 95% CI 1.68-8.68; p < 0.001), as well as with LFI (p = 0.042). Girls were at greater risk of LFI than boys (aOR 2.69, 95% CI 1.24-5.80; p = 0.012). Children whose mothers used charcoal or wood as cooking fuel had higher odds of respiratory symptoms (OR 2.61, 95% CI 1.22-5.58; p = 0.013) but no association was found with LFI (p = 0.459) compared with unexposed children. Conclusion Respiratory symptoms and lung function impairments were highly prevalent among children living disadvantaged, especially when mothers cook with wood or charcoal. Targeted maternal awareness and broader interventions to reduce household air pollution in disadvantaged urban areas are urgently needed to protect long-term respiratory health.

Background: Human activities such as mining generally lead to increased heavy metal concentrations in the environment. While traditional remediation techniques are often costly, the use of fungi as bioremediators, known as mycoremediation, is increasingly gaining attention as a sustainable approach for removal of heavy metals. Here, we evaluated heavy metal levels inside the Kiirunavaara iron ore mine in Northern Sweden and analysed fungal responses to various metal concentrations by comparing growth and metal uptake in mine-derived isolates and closely related control isolates. Results: Sediments inside the mine were enriched in heavy metals compared to those from the outlet of the mine to natural lakes. Six Fusarium isolates were recovered from contaminated mining environments: five isolates from inside the mine were identified as Fusarium oxysporum, and one isolate from the outlet was identified as Fusarium tricinctum. Isolates from the mine and outlet showed overall higher survival and biomass production in presence of copper, iron, and zinc across a range of concentrations (up to 1000 mg/L) compared to control isolates. At the same time, these isolates often exhibited reduced relative metal uptake. As a result, mycoremediation potential, assessed as total uptake in the grown mycelium, was isolate-dependent. Conclusions: Based on these results, we conclude that Fusarium isolates from the Kiirunavaara mine show increased growth in media enriched with heavy metals compared to closely related control isolates. We additionally show that mycoremediation potential is not necessarily associated with environmental origin. Instead, mycoremediation potential should be evaluated on a case-by-case basis for each isolate and based on specific needs for mycoremediation.

Background: Men with prostate cancer (PCa) may be especially vulnerable to per- and polyfluoroalkyl substances (PFAS) exposure due to their endocrine-disrupting and cardiometabolic impacts and cardiotoxicity and immune suppression of treatments. Objective: A pilot study was launched to measure serum and tap water PFAS concentrations in PCa survivors. Methods: Men with PCa were recruited from Rutgers Cancer Institute between February 2025 and March 2026, with ongoing enrollment and follow-up. Eligible men were aged [&ge;]40 years and either on active surveillance or within 3-12 months of initial definitive treatment. Participants provided blood and residential tap water samples, which were analyzed using mass spectrometry (serum) and modified EPA method 537 (water). Geometric means were used to summarize PFAS concentrations by race and assess serum-tap water correlations. Results: Of 235 eligible patients, 124 (60%) enrolled. Median age was 64 years; 63% were non-Hispanic White, 43% had a Gleason score [&le;]6. Roughly half of participants provided serum and/or tap water samples. In serum, six PFAS analytes had >80% detection; of these analytes, median concentrations ranged from 0.13 ng/mL (IQR: 0.07-0.20) for PFHpS to 2.55 ng/mL (IQR:1.54-3.82) for nPFOS. Among 74 tap water samples, 9 PFAS analytes had >60% detection; of these, median concentrations of PFNA (0.56 ng/L; IQR: 0.33-0.75), PFOA (3.75 ng/L; IQR: 1.21-5.27), and PFOS (2.29 ng/L; IQR: 0.46-2.89), were below New Jersey Maximum Contaminant Levels. Non-White participants had significantly higher levels of multiple PFAS analytes in both serum and tap water. Serum-tap water correlations were modest (r=0.22-0.41). Significance: The pilot study has demonstrated both the feasibility and importance of studying PFAS exposure pathways as well as potential impacts of PFAS exposure in diverse populations. Keywords: Prostatic Neoplasms, Per- and Polyfluoroalkyl Substances (PFAS), Biomonitoring, Environmental Exposure, Cohort Studies, Pilot study Impact Statement: This study provides some of the first estimates of PFAS exposure among prostate cancer patients in serum and tap water, showing moderate correlations between tap water and serum concentrations of specific PFAS analytes. These findings can support larger studies to identify environmental exposure sources and evaluate the role of PFAS in prostate cancer progression and outcomes.

Interest in microbiota-host co-metabolism and the effects of its derived co-metabolites on biological processes is increasing rapidly. In addition to their demonstrated associations with mammalian metabolic health and cognition, microbiota-host co-metabolites (MHCMs) represent lifelong contributors to the endogenous exposome. We have previously shown the MHCM trimethylamine N-oxide (TMAO) to exert beneficial effects on murine blood-brain barrier integrity and cognition. Here we investigated whether these positive neural effects of TMAO extended to humans, analysing how TMAO exposure associates with neurodevelopmental outcomes in children and whether an in vitro human neuronal-astrocyte co-culture could contribute to further investigation of the underlying mechanism(s) and neuronal processes related to these associations. In a cohort study of childhood mental health (N=1,203), TMAO was associated with fewer internalising problems, while its precursor microbial metabolite trimethylamine was associated with more behavioural problems in both the cross-sectional and an independent longitudinal study from 1 to 15 years of age (N=630-820). Given prior associations between TMAO exposure and exposure to the environmental pollutants mercury and arsenic, we investigated how the effects of TMAO interacted with these known neurotoxicants. TMAO had a protective effect, modifying the relationship between arsenic exposure and poorer neurodevelopmental outcomes. Furthermore, TMAO activated synaptogenesis-related gene expression and was functionally protective against the negative effects of mercury in our in vitro model. Together, our findings emphasise the importance of interdisciplinary approaches to evaluate associations and potential pathways of MHCMs (endogenous) and environmental (exogenous) metabolites on neurodevelopment in exposome studies.

Background: The effect of extreme temperatures on miscarriage is not well understood. Even less understood is the gestational period most vulnerable to extreme temperature exposure, as early miscarriages are often missed in incident datasets. We employ a birth-rate based approach to infer the risk of miscarriage in response to extreme temperature exposure by gestational week. Methods: We conducted a population-based ecological study using birth registry data from the 7,948 municipalities of Italy between 2013 and 2024 (4.5 million births). The analyses were stratified by five climatically coherent macro-regions (Ecoregions). To infer unreported pregnancy losses, we regressed birth rates dated from the last menstrual period against weekly temperatures across gestational weeks 3-21, accounting for temporal seasonality and spatial heterogeneities. Findings: Exposure to heat (mean weekly temperature of 30.4 degree/C) during gestational weeks 3-4 was associated with a reduction of birth rates of 1.62 (0.71 - 2.51)%, and of 1.91 (0.92 - 2.88)% to mean weekly temperature of 1.6 degree/C. Whilst heat was found to be harmful during gestational weeks 3-4 and 18-21, cold spells were found to be consistently harmful from the 3th up to the 12th week, depending on the Ecoregion. Interpretation: Pregnancies are vulnerable to extreme temperatures during the post-conceptual period and the second trimester. The findings underscore the need for a pre-conceptual cohort to clarify the mechanisms of loss, and urge public health action to protect pregnancies from the beginning of gestation.

Tenuazonic acid (TeA) is an emerging Alternaria mycotoxin frequently detected in food and feed commodities, raising concerns about its toxicological relevance. Chronic oral exposure to TeA has been reported to induce dysplastic alterations in the esophageal mucosa of mice, while human biomonitoring data indicate an association between TeA exposure and esophageal cancer, although a causal relationship has not yet been established. At a mechanistic level, the effects of TeA in esophageal cells remain poorly characterized. Therefore, this study investigated the impact of TeA on cytotoxicity, oxidative stress, DNA damage, mitochondrial homeostasis, cell-cycle distribution and transcriptomic stress responses in human esophageal KYSE-510 cells. TeA induced a concentration-dependent reduction in metabolic activity and total protein content after 24 h exposure to 0.1-100 M. Significant cytotoxicity was measured starting from 20 M. At sub-cytotoxic concentrations, TeA triggered rapid ROS formation within 5-30 min exposure and induced formamidopyrimidine-DNA glycosylase (FPG) sensitive DNA damage after 1 h exposure (5-7.5 M), indicating oxidative DNA lesions. In addition, TeA altered mitochondrial morphology after 4 h exposure at 7.5 M, manifested by shrinkage of the mitochondrial network area and perinuclear redistribution, while mitochondrial respiration showed only a non-significant tendency towards reduced respiratory capacity. RNA sequencing after 6 h exposure to 10 M TeA revealed oxidative stress-associated transcriptional changes, impaired antioxidant and stress-adaptive responses, and p53-associated stress signaling. Furthermore, TeA induced significant G2/M phase accumulation after 24 h exposure to 1-10 M.

Wastewater surveillance (WS) has been widely adopted as a cost-effective and population-representative infectious disease monitoring tool and is increasingly being applied to bacterial and antimicrobial resistance gene (ARG) targets. However, some of these targets may persist in pipe biofilms and detach into wastewater, complicating accurate WS interpretation. To investigate biofilm contributions to wastewater pathogen and ARG signals, paired sink-drain biofilm, branch-drain-plumbing biofilm (sewer biofilm), and wastewater were collected from five hospital sites over a four-month period and analyzed using 16S rRNA gene amplicon sequencing and probe-capture metagenomics. Overall, sewer biofilm bacterial communities were as diverse as wastewater. Across sites, a mean of 9% (0.9 to 23.3%) of wastewater bacterial communities could be attributed to sewer biofilm communities. Many clinically relevant pathogens were consistently detected both in sewer biofilm and wastewater, including environmentally persistent and/or biofilm-associated taxa (e.g., Pseudomonas aeruginosa, Klebsiella pneumoniae). While many ARGs overlapped between wastewater and biofilms (e.g., tetA, sul1, blaCTX-M, vanA), others were significantly enriched in sewer biofilms (e.g., qacL, van-operon and OXA genes). Together, these findings confirm that wastewater pathogen and resistome profiles integrate inputs from both human shedding and pipe-resident communities and therefore need to be considered when selecting WS targets and interpreting signal.

The use of nitrogen (N) fertilizers to meet global food demands is expected to continue rising. However, up to 70% of N applied to agricultural soils is lost through microbially mediated processes such as nitrification. Inhibiting nitrification is thus a key strategy to reduce N losses and improve fertilizer N use efficiency. Various plant-derived compounds, termed biological nitrification inhibitors (BNIs), have been shown to reduce accumulation of nitrification products, intermediates, and byproducts (nitrite, nitrate, nitric and nitrous oxides). However, the mechanisms by which BNIs affect nitrifiers, along with their specificity and persistence in soil are not well understood. Here, we evaluated the effects of three BNIs: methyl 3-(4-hydroxyphenyl) acrylate (MHPA), 6-methoxy-2(3H)-benzoxazolone (MBOA), and limonene, on ammonia-oxidizing, total microbial, and fungal communities in two soils with contrasting pH. Their persistence in each soil was also evaluated. Although ammonia-oxidizing archaea initially dominated nitrifier communities in both soils, their bacterial counterparts significantly increased after mineral N addition but also were more sensitive to BNI application. Limonene and the synthetic inhibitor DMPP stimulated ammonium immobilization, as total soil mineral N was significantly reduced. Limonene and MHPA had the strongest off-target effects, increasing the relative abundance of hydrocarbon-degrading bacteria and potential fungal pathogens, respectively. In contrast, MBOA inhibited nitrification with minimal off-target effects. Among the tested BNIs, MBOA was also the most persistent in the high-pH, high-nitrification-rate soil. Our results show that MBOA is a promising biological inhibitor and highlight the importance of understanding BNIs ecological effects to develop targeted and sustainable N management strategies.

Fine particulate air pollution (PM2.5) in the United States has fallen by roughly half since 2000, yet linked health outcomes such as diabetes and childhood ADHD have not improved in parallel. One reconciling possibility is that pollution exposure in early life produces health effects that emerge only years or decades later, after pollution itself has declined. Using two decades of U.S. county-level data, we relate annual PM2.5 estimates to birth outcomes, diabetes prevalence, and small-area estimates of childhood attention-deficit/hyperactivity disorder (ADHD) across short and long time scales. Within counties, changes in low birth weight rates are associated with changes in PM2.5 during the same year and the year prior to birth. At longer time scales, cross-county comparisons show that PM2.5 exposure is associated with higher prevalence of adult diabetes and ADHD after approximately a decade. Together, these patterns suggest that population-level health risks from air pollution may persist over decades, even as pollution itself declines.

Short-term environmental exposures have been linked to cognitive and attention-related outcomes, but the robustness of these associations remains uncertain. We linked daily weather and air-pollution exposures to repeated measures of subjective cognitive difficulties and attention-related outcomes among participants in the All of Us Research Program from 2018 to 2024. Associations were evaluated using complementary longitudinal and causal-inference approaches, including fixed-effects, lagged-exposure, and event-study analyses. Machine-learning methods were used to characterize heterogeneity and latent psychosocial structure, and findings were independently evaluated using 2024 Behavioral Risk Factor Surveillance System data. Several environmental exposure measures were associated with cognitive outcomes in pooled analyses; however, most associations attenuated substantially after accounting for within-location temporal variation. In contrast, mental-health burden, loneliness, and impaired social functioning remained consistently associated with subjective cognitive difficulty across analytical approaches. Similar patterns were observed in the validation dataset. These findings suggest that some observed environmental associations may reflect broader geographic and contextual differences rather than short-term environmental effects. Overall, psychosocial factors demonstrated more consistent associations with subjective cognitive difficulties than short-term environmental exposures across multiple analytical frameworks and independent datasets.

Chemically complex pharmaceutical mixtures in wastewater and sludge can affect microbial adaptation; however, the responses to different co-occurring compounds have not been elucidated well. In this study, the adaptation of a strain derived from hospital sludge, Klebsiella pneumoniae SS02, to 17-ethinylestradiol (EE2), warfarin sodium, and their combination has been studied. The organism grows under all three conditions, and pre-exposure experiments show induction and cross-induction to substrates. UHPLC MS/MS analyses demonstrated that there is conditional depletion of the parent compound EE2 by [~]15% at 36 h post-treatment compared to initial concentrations, but not for the abiotic and non-adapted controls. The rate of warfarin sodium depletion was approximately [~]30% within 36 h and was in accordance with first order kinetics (k = 0.0102 /h; t{square}/{square}= 67.9 h). Under the combined treatment regime, there was a delay in warfarin sodium depletion, suggesting staged substrate consumption. Growth inhibition with efflux inhibitors confirmed transport-driven tolerance. A genome-based study revealed the coordinated response strategy that involved a proposed flavin-dependent monooxygenase (RutA), an oxidative entry into the pathway; redox processing linked to Hpa; aromatic metabolism through {beta}-ketoadipate pathway; and RND efflux system. The structural study additionally supported ligand-mediated decrease in DNA binding affinity of RutR, which is in agreement with de-repression of the substrate-activated regulatory mechanism. All these findings lead to the development of a dual-strategy for adaptation model in which oxidative modification and efflux-mediated protection work together under the influence of a mixture of pharmaceuticals.

The soil priming effect plays an important role in the global carbon cycle. Although well-studied, the mechanisms behind it remain elusive. So far, studies measured the phenomenon at the bulk soil scale, neglecting that it arises from spatially explicit processes that take place at the microscale. Here, we present a novel approach using a microfluidic device to directly assess the response of soil microbes living on a patch of complex substrate to a pulse of easily available substrate. Using time-resolved fluorescence microscopy, we tracked motility, position, shape characteristics and attached biomass of green fluorescent protein expressing Bacillus subtilis cells living on a transparent carboxymethylcellulose substrate patch exposed to a pulse of growth medium with differing concentrations. Assessing CMC decomposition via Congo-Red staining after 42 days of incubations with constant observation, we observed increased decomposition upon addition of enough labile substrate, resembling a priming effect. The pulse triggered a transient increase in bacterial motility, indicating the formation of exploring and growing subpopulations respectively. We observed a concentration-dependent growth response, resulting in different behaviors. High concentrations led to high biomass and decomposition of CMC, however growth was quickly limited, possibly by depletion of necessary nutrients and waste accumulation. Intermediate concentration, however, resulted in a more sustained attached biomass, that showed evidence of spatial self-organization, leading to similar decomposition. We present a novel experimental model system to study the behavior of soil microbes decomposing complex substrate and provide a unique view into the response of such a population to a labile substrate pulse.

Rare earth elements (REEs) are critical components of green technologies, but current mining and purification methods remain environmentally unsustainable due to their high energy consumption and intensive chemical requirements. Bio-hydrometallurgical processes have the potential to concentrate and recover REEs at a circumneutral pH. Work presented here uses bacteria at neutral pH to concentrate REEs from solution and subsequently recover those REEs using sodium citrate. Shewanella oneidensis MR-1 was incubated anaerobically in a culture media solution spiked with 14 REEs and yttrium for one to six days. REE concentrations remaining in solution were then compared to REE concentrations on cell pellets. For these same timepoints, the loosely bound extracellular polymeric substance (LB-EPS) was removed from cells prior to quantifying REEs on pellets to narrow down the location of REE binding. Moreover, cell pellets collected after 5 days in REE spiked solution were subjected to a time series desorption assay using sodium citrate. Shewanella oneidensis at a starting OD600 of 0.6 adsorbed 1.18mg/g of REE after 3 days. 80% of these REEs were located in the LB-EPS. In 10 minutes, 0.5 M sodium citrate desorbed about 75% of REEs from cells and over 95% after 24 hours. This method was also applied to Alaskan coal and showed that 68-86% of REEs were desorbed form S. oneidensis. This study elucidates the REE binding location and capacity of S. oneidensi, REE removal efficiency of sodium citrate overtime, and the application of this sustainable biotechnology for REE recovery at a circumneutral pH from Alaskan coal.

Manual intervention for concrete repair and replacement comes at high environmental and economic costs. Bioconcrete, which can be formed by bacteria via microbially-induced carbonate precipitation (MICP), is a sustainable method for concrete repair. Bioconcrete-forming bacteria can be incorporated into the concrete at mixing and then heal cracks where and when they occur. Bioconcrete is not intentionally made by bacteria; rather, it is a byproduct of alterations to the local environment that occur during their normal metabolic activities. Bacteria thus make bioconcrete by different metabolic mechanisms, and the environment plays a substantial role in the yield and physical properties of the bioconcrete produced by a given bacterium. The ureolytic bacterium Sporosarcina pasteurii is the most commonly used model organism for MICP, but it requires urea supplementation, which is not feasible for all applications because of nitrogenous waste. In particular, the marine environment is understudied for bioconcrete applications, yet there is a need for self-healing structures in this environment, wherein urea and nitrogenous waste would be detrimental to native biota. Here, we assessed the ability of S. pasteurii to form bioconcrete under marine-like media conditions with urea and calcium supplementation. We found that S. pasteurii generated higher bioconcrete yields in these media conditions compared to standard growth media. We then designed an enrichment protocol to isolate and characterize non-urea-requiring bioconcrete-forming bacteria from Atlantic seawater. We identified three isolates, from the Sulflitobacter, Marinobacter, and Bacillus genera, two of which yielded higher bioconcrete yields in seawater-mimicking media compared to non-ureolytic bacteria utilized in prior literature. Moreover, scanning electron microscopy (SEM)/energy dispersive spectroscopy (EDS) and Fourier transform infrared (FTIR) spectroscopy revealed distinct chemical and structural features of the bioconcrete produced by bacteria in seawater-mimicking medium and between ureolytic and non-ureolytic cultures. Overall, our work establishes a pipeline for the isolation and characterization of novel bioconcrete-forming bacteria from marine samples, with potential for application to marine self-healing materials.

Carbapenem-resistant Acinetobacter (CRA) has been associated with increased morbidity and mortality in clinical settings. In this study, we explored the transfer potential of a mobilizable plasmid-harboring blaOXA-72 gene between Acinetobacter species originating from patient, municipal wastewater, and pig farm wastewater. PCR-based evidence suggested putative transfer of blaOXA-72 from Acinetobacter pittii to Acinetobacter baumannii. In this pair, the apparent frequency of PCR-marker-positive putative transconjugants varied depending on temperature and meropenem supplementation, with higher number observed at 27{degrees}C compared to 17{degrees}C and 37{degrees}C. Likewise, the presence of antibiotic pressure yields to higher apparent conjugation frequency, however this observation was limited to a singled donor-recipient pair. Further, we revealed a phenotypic conversion in terms of meropenem susceptibility and a fitness cost in the putative transconjugants. While whole genome sequencing did not conclusively verify the presence of blaOXA-72 or fully resolved plasmid configuration, Oxford Nanopore read mapping consistently detected the chromosomal strA gene in all isolates. In contrast, only a limited number of reads aligned with blaOXA-72 gene, traC, or the complete plasmid sequences. Comparative analyses further revealed variations in the surface-associated factors and defense systems composition of the recipient strains, which could be considered as barriers in conjugation. Lastly, the persistence of PCR-detectable marker genes in putative transconjugants was variable and generally unstable over a 30-day period. Overall, these findings provide preliminary insights into the factors that may influence horizontal gene transfer and short-term maintenance of blaOXA-72.

From Brazilian limestone caves, we isolated 29 bacteria utilizing phenol (23 bacteria), toluene (all bacteria), and/or benzene (all bacteria) as sole carbon sources. One isolate showed phosphate solubilization, while lipase/esterase activity occurred in two isolates; no amylase activity was detected, but 16 isolates ([~]55%) exhibited protease activity. Among them, Nocardioides sp. SF1 was selected for whole-genome sequencing due to its aromatic compound tolerance and protease activity. Additionally, catechol cleavage assays yielded unexpected purple pigmentation, suggesting non-canonical aromatic metabolism. Its high-quality draft genome (4.25 Mbp, 16 contigs, N50 of 887 kb) lacks canonical phenol hydroxylase but encodes alternative oxidation systems, phenylacetyl-CoA pathway, besides, desferrioxamine siderophore, biosurfactants, and phosphate solubilization, key adaptations for oligotrophic caves and biotechnologically interesting activities. Whole-genome comparisons (TYGS/GGDC, OrthoANI and k-mer) suggest potential new species. Lacks acquired antimicrobial resistance genes (ResFinder) and pathogenicity potential (PathogenFinder). Nocardioides sp. SF1 emerges as a non-pathogenic candidate for aromatic bioremediation and plant growth promotion in contaminated, nutrient-poor environments, highlighting cave actinobacterias unexplored biotechnological potential.

Antimicrobial resistance (AMR) is increasingly recognized as an ecological and evolutionary phenomenon that extends beyond clinical environments. Despite the predominant focus on antibiotics, bacterial metal resistance genes are among the oldest and most widespread adaptive antimicrobial systems, yet their distribution within human-associated microbial communities remains poorly characterized. Here, we investigated the ecology of mercury (Hg) resistance in children from a birth cohort with relatively high Hg exposure. Fecal samples from 234 children aged 4-8 years were analyzed using culture-based screening, whole-genome sequencing, and comparative analyses of metal- and antibiotic-resistance determinants and associated mobile genetic elements (MGEs). Hg-resistance was detected in 79.7% of samples, with HgR Enterobacterales isolated from 57% of children. Hair mercury concentrations were not associated with carriage. Sequencing revealed a phylogenetically diverse collection dominated by Escherichia spp. (61%). Hg resistance was mediated by 79 mer operons primarily associated with Tn21, Tn1696, and Tn5053 families circulating on chromosomes and a highly diverse plasmidome. Both rare and globally distributed plasmids related to foodborne, animal, and clinical Enterobacterales were identified. Metal resistance determinants exhibited strong taxonomic structuring, with Escherichia enriched in iron-uptake systems and siderophores whereas non-Escherichia taxa carried multimetal resistance operons. These findings indicate that Hg-resistance is shaped by ecological interactions and MGEs, becoming partially decoupled from contemporary Hg-exposure and bacterial community composition. The human gut therefore serves as an important reservoir linking environmental metal resistance to the broader evolution of AMR and provides insight into the baseline resistome and plasmidome of human populations.