There is interest in exploring biodegradable chemicals, e.g. sex pheromones, in behaviour manipulation to control the polyphagous mirid species Helopeltis bakeri Poppius. Understanding this insect pest’s reproductive behaviour is critical for identifying and isolating semiochemicals. H. bakeri rate of sexual maturation was determined by identifying the time the winged adult changed colour after the 5th and final nymphal form. We verified that there was no significant difference in the rate of colour change for both sexes. Copulation lasted an average of 167.0 ± 77.1 min and was observed on mating pairs >72 h old from the time of final molt. Close-range copulation behaviour of H. bakeri was recorded using the Behavioral Observation Research Interactive Software, and sequential behaviour analysis was performed by creating adjacency matrices. The ethograms revealed the absence of specific calling behaviour from either of the sexes. However, the male’s active pursuit of the female may indicate the latter’s role in releasing sex attractants. Using a wind tunnel, it was observed that the number of male visitations of 96-h to 120-h-old females significantly differed from the attraction in younger females (p < 0.05) and peaked from 2:00 PM to 12:00 AM. This supports the crepuscular nature of this mirid species. The difference in the sex maturation age and maximum male attraction implies that the secretion of sex attractant could happen after the completion of development, i.e. the exhibition of colour dimorphism.

Exploring diversity and community composition patterns across evolutionary and functionally diverse organisms is critical for understanding the general processes that shape biodiversity in response to environmental changes. Knowledge of multi-trophic relationships offers valuable insights to support the effective assessment and management of freshwater ecosystems. In this study, we conducted a cross-taxa assessment of benthic macroinvertebrates and microorganisms using metabarcoding-based surveys to evaluate habitat restoration in a dam-impacted river. We found no correlation between the α-diversity of the benthic macroinvertebrate and microbial communities. This suggests that factors influencing the α-diversity of different trophic groups might operate independently or through different mechanisms, even within the same habitat. In contrast, we observed positively correlated β-diversity patterns between the two benthic communities influenced by dam fragmentation and gravel bar restoration. This suggests that environmental heterogeneity between sites may have a common influence on the patterns of pairwise dissimilarities in the benthic communities, even though they have significant differences in key traits, e.g., species composition, functional roles, or trophic level. Additionally, phylogenetic structure analysis revealed a greater dam impact on benthic macroinvertebrates than microbial communities. Benthic microorganisms consistently formed phylogenetically clustered communities regardless of dam impact, while the macroinvertebrates shifted from competitive exclusion to environmental filtering in response to dam fragmentation. Our cross-taxa assessment further explained the relationships among benthic communities and their associations with environmental factors in a river ecosystem undergoing habitat restoration. Our study highlights the significant implications of evaluating different biological communities across trophic levels for river restoration strategies and ecosystem assessment.

Background  Antimicrobial resistance is a major global health concern, with the environment playing a key role in its emergence and spread. Understanding the relationships between environmental factors, microbial communities, and resistance mechanisms is vital for elucidating environmental resistome dynamics. In this study, we characterized the environmental resistome of the Baltic Sea and evaluated how environmental gradients and spatial variability, alongside its microbial communities and associated functional genes, influence resistome diversity and composition across geographic regions.

Results  We analyzed the metagenomes of benthic sediments from 59 monitoring stations across a 1,150 km distance of the Baltic Sea, revealing an environmental resistome comprised of predicted antimicrobial resistance genes (ARGs) associated with resistance against 26 antibiotic classes. We observed spatial variation in its resistance profile, with higher resistome diversity in the northern regions and a decline in the dead zones and the southern areas. The combined effects of salinity and temperature gradients, alongside nutrient availability, created a complex environmental landscape that shaped the diversity and distribution of the predicted ARGs. Salinity predominantly influenced microbial communities and predicted ARG composition, leading to clear distinctions between high-saline regions and those with lower to mid-level salinity. Furthermore, our analysis suggests that microbial community composition and mobile genetic elements might be crucial in shaping ARG diversity and composition.

Conclusions  We presented that salinity and temperature were identified as the primary environmental factors influencing resistome diversity and distribution across geographic regions, with nutrient availability further shaping these patterns in the Baltic Sea. Our study also highlighted the interplay between microbial communities, resistance, and associated functional genes in the benthic ecosystem, underscoring the potential role of microbial and mobile genetic element composition in ARG distribution. Understanding how environmental factors and microbial communities modulate environmental resistomes will help predict the impact of future environmental changes on resistance mechanisms in complex aquatic ecosystems.

Background  The Baltic Sea receives petroleum hydrocarbons from various point sources. The degradation of these contaminants in the environment is typically facilitated by a variety of microorganisms that possess a range of genes and metabolic functions related to the degradation of various hydrocarbon substrates. However, our understanding of natural attenuation and the microbial capacity to degrade these contaminants within the Baltic Sea ecosystem remains limited. In this study, we compiled metagenomes from the benthic and pelagic ecosystems across the Baltic Sea to identify microorganisms and characterize their genes and metabolic functions involved in the degradation of hydrocarbon compounds.

Results  Known hydrocarbon-degrading phyla, i.e., Pseudomonadota, Myxococcota A, Actinomycetota, and Desulfobacterota, were identified within the Baltic Sea metagenome-assembled genomes (MAGs). Notably, 80% of the MAGs exhibited multiple hydrocarbon degradation gene annotations (> 10 reads per kilobase million). Aerobic degradation was the predominant pathway for hydrocarbon degradation across environmental samples. Hydrocarbon degradation gene abundances varied among samples and Baltic Sea subbasins, with long-chain alkanes and dibenzothiophene compounds being the preferred substrates. Species richness and diversity of both benthic and pelagic microorganisms positively correlated with hydrocarbon degradation gene diversity, with the pelagic ecosystem exhibiting significantly higher richness and diversity compared to the benthic ecosystem. Additionally, the composition of the hydrocarbon degradation genes across the Baltic Sea subbasins was influenced by oil spill history, with areas that experienced higher spill volumes showing lower microbial diversity, suggesting potential enrichment of specific hydrocarbon degraders. Among the environmental factors assessed, depth played a significant role in shaping the composition of genes involved in hydrocarbon degradation within the Baltic Sea.

Conclusions  Using metagenomics, we profiled the native microorganisms associated with hydrocarbon degradation in the Baltic Sea. This knowledge will aid in understanding the natural capacities of microbial communities, potentially linked to the natural attenuation of hydrocarbon pollutants in the area. Insights into microbial degradation potential can enhance predictions of petroleum pollutant persistence and accumulation, support mitigation strategies for marine pollution, and reveal the ecological resilience of native microbial communities in marine ecosystems.

Therapeutic compounds exert impacts on gut microbiota; however, how they affect the community functional ecology, especially as reflected at the protein level, remains largely unexplored. In this study, we systematically map metaproteomic responses of ex vivo human gut microbiota to 312 compounds, generating 4.6 million microbial protein responses, available as an interactive resource (https://shiny.imetalab.ca/MPR_Viz/). Protein-level analyses identify significant metaproteomic shifts induced by 47 compounds, with neuropharmaceuticals as the sole drug class significantly enriched among these hits. Further analyses on the community level reveal a tri-stability pattern in microbial composition and the emergence of three distinct functional states, based on a functional beta-diversity metric. Notably, neuropharmaceuticals cause particularly strong effects on the microbiomes, lowering the proteome-level functional redundancy and raising the level of antimicrobial resistance proteins, ultimately pushing the microbiome into an alternative functional state. Preliminary validation suggests that enhancing functional redundancy may contribute to maintaining microbiota resilience against neuropharmaceutical-induced antimicrobial resistance. Overall, this work establishes a comprehensive view of how drugs influence gut microbiome function and ecology at the protein level, proposes a landscape-based framework for interpreting community resilience, and highlights the need to consider protein-level and ecological responses in the evaluation of therapeutic interventions.