Significant Differences In Diversity Research Articles

Exploring riverine aquatic animal diversity and establishing aquatic ecological monitoring approaches tailored to the Qinling region via eDNA technology.

This study thoroughly examines biodiversity and aquatic ecosystems across 14 sampled sites within the Shitou River basin by utilizing environmental DNA technology. Through integrated analysis and high-throughput sequencing, the study elucidates a diverse array of biodiversity, encompassing 27 fish species and 341 freshwater benthic macroinvertebrates (FBM) species. Using various biodiversity indices, we found significant differences in diversity and stability across different environments. Regions with more complex habitats had higher species richness and evenness. Further analyses showed complex relationships between diversity metrics for FBM and fish, indicating potential interactions between these groups. The standardized mean score (SMS) was developed to aid in the assessment of water quality. Specifically, SMS scoring revealed that sites STH3, STH4, and STH14 excelled across multiple dimensions, earning an "Excellent" rating, while site STH12 was rated as "Poor" due to subpar performance across several metrics. This project not only enhances current understanding regarding aquatic ecological dynamics but also establishes a strong foundation for detailed environmental evaluation and monitoring, aligned with the priorities of contemporary ecological management and caution.

Fungal community characteristics of the last remaining habitat of three paphiopedilum species in China.

Paphiopedilum armeniacum, Paphiopedilum wenshanense and Paphiopedilum emersonii are critically endangered wild orchids. Their populations are under severe threat, with a dramatic decline in the number of their natural distribution sites. Ex situ conservation and artificial breeding are the keys to maintaining the population to ensure the success of ex situ conservation and field return in the future. The habitat characteristics and soil nutrient information of the last remaining wild distribution sites of the three species were studied. ITS high-throughput sequencing was used to reveal the composition and structure of the soil fungal community, analyze its diversity and functional characteristics, and reveal its relationship with soil nutrients. The three species preferred to grow on low-lying, ventilated and shaded declivities with good water drainage. There were significant differences in soil alkali-hydrolyzed nitrogen and available phosphorus among the three species. There were 336 fungal species detected in the samples. On average, there were different dominant groups in the soil fungal communities of the three species. The functional groups of soil fungi within their habitats were dominated by saprophytic fungi and ectomycorrhizae, with significant differences in diversity and structure. The co-occurrence network of habitat soil fungi was mainly positive. Soil pH significantly affected soil fungal diversity within their habitats of the three paphiopedilum species. The study confirmed that the dominant groups of soil fungi were significantly correlated with soil nutrients. The three species exhibit comparable habitat inclinations, yet they display substantial variations in the composition, structure, and diversity of soil fungi. The fungal functional group is characterized by a rich presence of saprophytic fungi, a proliferation of ectomycorrhizae, and a modest occurrence of orchid mycorrhizae. The symbiotic interactions among the soil fungi associated with these three species are well-coordinated, enhancing their resilience against challenging environmental conditions. There is a significant correlation between soil environmental factors and the composition of soil fungal communities, with pH emerging as a pivotal factor regulating fungal diversity. Our research into the habitat traits and soil fungal ecosystems of the three wild Paphiopedilum species has established a cornerstone for prospective ex situ conservation measures and the eventual reestablishment of these species in their native landscapes.

Extreme trophic tales: deciphering bacterial diversity and potential functions in oligotrophic and hypereutrophic lakes

BackgroundOligotrophy and hypereutrophy represent the two extremes of lake trophic states, and understanding the distribution of bacterial communities across these contrasting conditions is crucial for advancing aquatic microbial research. Despite the significance of these extreme trophic states, bacterial community characteristics and co-occurrence patterns in such environments have been scarcely interpreted. To bridge this knowledge gap, we collected 60 water samples from Lake Fuxian (oligotrophic) and Lake Xingyun (hypereutrophic) during different hydrological periods.ResultsEmploying 16S rRNA gene sequencing, our findings revealed distinct community structures and metabolic potentials in bacterial communities of hypereutrophic and oligotrophic lake ecosystems. The hypereutrophic ecosystem exhibited higher bacterial α- and β-diversity compared to the oligotrophic ecosystem. Actinobacteria dominated the oligotrophic Lake Fuxian, while Cyanobacteria, Proteobacteria, and Bacteroidetes were more prevalent in the hypereutrophic Lake Xingyun. Functions associated with methanol oxidation, methylotrophy, fermentation, aromatic compound degradation, nitrogen/nitrate respiration, and nitrogen/nitrate denitrification were enriched in the oligotrophic lake, underscoring the vital role of bacteria in carbon and nitrogen cycling. In contrast, functions related to ureolysis, human pathogens, animal parasites or symbionts, and phototrophy were enriched in the hypereutrophic lake, highlighting human activity-related disturbances and potential pathogenic risks. Co-occurrence network analysis unveiled a more complex and stable bacterial network in the hypereutrophic lake compared to the oligotrophic lake.ConclusionOur study provides insights into the intricate relationships between trophic states and bacterial community structure, emphasizing significant differences in diversity, community composition, and network characteristics between extreme states of oligotrophy and hypereutrophy. Additionally, it explores the nuanced responses of bacterial communities to environmental conditions in these two contrasting trophic states.

Profiling the dynamic adaptations of CAZyme-Producing microorganisms in the gastrointestinal tract of South African goats

The gastrointestinal tract of goats serves as a habitat for anaerobic microbial populations that work together to break down complex plant material, including lignocellulose. This study explored the microbial diversity and metabolic profiles across different gastrointestinal tract compartments. Significant diversity differences among the compartments were observed (ANOSIM p < 0.006), with the abomasum showing a distinct species composition and a decreased alpha diversity (Mann-Whitney/Kruskal-Wallis test p = 0.00096), possibly due to its acidic environment. Dominant microbial phyla included Proteobacteria, Bacteroidetes, and Firmicutes, with Proteobacteria being the most prevalent in the abomasum (50.06 %). Genera like Proteus and Bacteroides were particularly prominent in the rumen and reticulum, highlighting their significant role in feed degradation and fermentation processes. Over 65 % of genes at Kyoto Encyclopedia of Genes and Genomes level 1 were involved in metabolism with significant xenobiotic biodegradation in the abomasum. The dbCAN2 search identified Glycoside Hydrolases as the most prevalent CAZyme class (79 %), followed by Glycosyltransferases, Polysaccharide Lyases, and Carbohydrate Esterases, with Carbohydrate-Binding Modules and Auxiliary Activities accounting for 1 % of the hits. Higher CAZyme abundance was observed in the reticulum and omasum compartments, possibly due to MAGs diversity. In conclusion, the gastrointestinal tract of South African goats harbors diverse CAZyme classes, with Glycoside Hydrolases predominating. Interestingly, higher CAZyme abundance in specific compartments suggested compartmentalized microbial activity, reflecting adaptation to dietary substrates.

Analyzing Species Diversity in Rocky Intertidal Communities over Multiple Spatial Scales among Understudied Eastern Pacific Ecoregions

Many gaps in our theoretical understanding of the variations in the diversity and structure of intertidal communities exist for the Eastern Pacific. In order to fill some of these gaps, we censused intertidal communities and compared patterns of diversity on multiple spatial scales using several measures in alpha (α) and beta (β) diversities at twenty-one sites in a cold temperate, a warm temperate and a tropical Eastern Pacific ecoregion that were unique in terms of research effort and each with distinct geographic features. Diversity and richness on all spatial scales were compared using area curves, Hill numbers, ordination and cluster analyses, and the Hutcheson’s t-test with post hoc PERMANOVA, which revealed significant differences in diversity within and among ecoregions. Functional group and species richness and abundance were found to be highest in the cold and warm temperate ecoregions, and the functional group richness was second highest in the tropical Guayaquil ecoregion. The Bray–Curtis similarity method proved useful for determining patterns of small-scale intertidal zonation, while the Sorensen–Dice method suggested high indices of similarity in the functional group and subclass structures among all ecoregions.

Gut microbiota in preterm infants with late-onset sepsis and pneumonia: a pilot case-control study

BackgroundLate-onset sepsis (LOS) and pneumonia are common infectious diseases, with high morbidity and mortality in neonates. This study aimed to investigate the differences in the gut microbiota among preterm infants with LOS, or pneumonia, and full-term infants. Furthermore, this study aimed to determine whether there is a correlation between intestinal pathogenic colonization and LOS.MethodsIn a single-center case‒control study, 16 S rRNA gene sequencing technology was used to compare gut microbiota characteristics and differences among the LOS group, pneumonia group, and control group.ResultsOur study revealed that the gut microbiota in the control group was more diverse than that in the LOS group and pneumonia group (P < 0.05). No significant differences in diversity were detected between the LOS and pneumonia groups (P > 0.05). Compared with the control group, the abundances of Akkermansia, Escherichia/Shigella, and Enterococcus increased, while the abundances of Bacteroides and Stenotrophomonas decreased in the LOS and pneumonia groups. The pathogenic bacteria in infants with LOS were consistent with the distribution of the main bacteria in the intestinal microbiota. An increase in Escherichia/Shigella abundance may predict a high risk of LOS occurrence, with an area under the curve (AUC) of 0.773.ConclusionChanges in the gut microbiota composition were associated with an increased risk of LOS and pneumonia. The dominant bacteria in the gut microbiota of the LOS group were found to be associated with the causative pathogen of LOS. Moreover, preterm infants exhibiting an elevated abundance of Escherichia/Shigella may be considered potential candidates for predicting the onset of LOS.

Relating gut microbiome composition and life history metrics for pronghorn (Antilocapra americana) in the Red Desert, Wyoming.

Host microbial communities (hereafter, the 'microbiome') are recognized as an important aspect of host health and are gaining attention as a useful biomarker to understand the ecology and demographics of wildlife populations. Several studies indicate that the microbiome may contribute to the adaptive capacity of animals to changing environments associated with increasing habitat fragmentation and rapid climate change. To this end, we investigated the gut microbiome of pronghorn (Antilocapra americana), an iconic species in an environment that is undergoing both climatic and anthropogenic change. The bacterial composition of the pronghorn gut microbiome has yet to be described in the literature, and thus our study provides important baseline information about this species. We used 16S rRNA amplicon sequencing of fecal samples to characterize the gut microbiome of pronghorn-a facultative sagebrush (Artemisia spp.) specialist in many regions where they occur in western North America. We collected fecal pellets from 159 captured female pronghorn from four herds in the Red Desert of Wyoming during winters of 2013 and 2014. We found small, but significant differences in diversity of the gut microbiome relative to study area, capture period, and body fat measurements. In addition, we found a difference in gut microbiome composition in pronghorn across two regions separated by Interstate 80. Results indicated that the fecal microbiome may be a potential biomarker for the spatial ecology of free-ranging ungulates. The core gut microbiome of these animals-including bacteria in the phyla Firmicutes (now Bacillota) and Bacteroidota-remained relatively stable across populations and biological metrics. These findings provide a baseline for the gut microbiome of pronghorn that could potentially be used as a target in monitoring health and population structure of pronghorn relative to habitat fragmentation, climate change, and management practices.

Keragaman Arthropoda pada Teknologi Bujangseta di Tanaman Jeruk Siam

Bujangseta is a technology used throughout the year to produce citrus fruits. This technology has economically succeeded in increasing the income of citrus farmers by 23.5%. Sustainable management of bujangseta technology is neede, one of which is maintaining the sustainability of the agroecosystem. A stable agroecosystem ensures the availability of ecosystem services through nutrient cycling and the natural control of pest and disease populations. The stability of agroecosystems is coherent with the high biodiversity of arthropods. This study aims to evaluate the effect of applying the citrus plant bujangseta in Karangwidoro village and Krajan village, Dau District, Malang Regency, East Java, from June to December 2022. The two application methods were light trapping (lighttrap) and pit trap (pitfall glass), and the results were analyzed using a t-test. The diversity index, species richness index, species evenness index, and dominance index were calculated. The results showed that the detrivores of the Collembola group dominated the diversity of arthropods, the primary pest of the Diaphorina citri, and the predatory arthropods of Paederus sp. and Braconidae. Diversity and community structure of arthopods indicated there at significant differences in diversity, dominance, evenness, and species richness in those two locations. Bujangseta in the Krajan has a higher community structure compared to the Karangwidoro, showing that the ecosystem at the Krajan location is better preserved. Keywords: arthropods, bujangseta, citrus, community structure

Abstract 1173: T cell receptor diversity in buffy coat samples from subsets of breast and ovarian cancer patients

Abstract Background: Immunotherapy, mainly by the use of immune checkpoint inhibitors (ICI), has been established as a standard option for both, solid tumors and hematological malignancies. Unfortunately, this success has only been replicated in a subset of patients (pts) with gynecological cancers. In ovarian cancer (OC), response rates to ICI monotherapy were low and in breast cancer (BC), only the subgroup of triple-negative BC (TNBC) pts showed an improved outcome by the addition of ICI. One reason for limited success of immunotherapy might be an impaired immune system. In this regard, monitoring the T cell receptor (TCR) repertoire could provide key insights into adaptive immune responses to ultimately understand disease initiation, progression and treatment response. Here we elucidated TCR alpha, beta, gamma and delta in buffy coats of pts with non-metastatic OC as well as non-metastatic and metastatic TNBC and compared the results with healthy donors (HDs). Methods: RNA was isolated from buffy coat samples of 20 HDs, 10 treatment-naïve primary OC pts, 14 treatment-naïve, non-metastatic TNBC pts (participating in the phase II neomono trial) and 19 pts with metastatic TNBC by a modified QIAamp RNA Blood Mini protocol. A survey of the TCR diversity and mapping of common and unique TCRs was done using the QIAseq Targeted RNA Panel Human TCR panel for all known T-cell receptors (alpha, beta, gamma, delta). Results: Regardless of the cancer entity, a significant reduction in TCR diversity was observed compared to HDs with the greatest differences observed in the delta receptors. When OC samples were compared with HDs, the difference in diversity was highly significant for all TCR subtypes (TCRalpha: p=0.013; TCRbeta: p=0.008; TCRgamma: 0.008; TCRdelta: 0.006). Similar results were obtained for non-metastatic TNBC (TCRalpha: p=0.0002; TCRbeta: p=0.0001; TCRgamma: p=0.002; TCRdelta: p=0.002) as well as metastatic TNBC patients (TCRalpha: p=0.001; TCRbeta: p=0.001; TCRgamma: p=0.005; TCRdelta: p=0.003) when their TCR diversity was compared to HDs. Interestingly, no significant differences in diversity were obtained when treatment-naïve non-metastatic TNBC pts were compared with heavily pretreated metastatic TNBC pts. The lowest diversity was found in BC pts compared to the OC pts. Conclusion: We have initiated a survey of the TCR diversity in TNBC and OC patients. Further evaluations will include the correlation of these findings with clinical characteristics and outcome. Whether the reduced TCR diversity represents T cell exhaustion or T cell specialization cannot yet be deduced from the results. Nevertheless, the addition of a TCR diversity score could provide an additional metric which may help provide patient guidance when integrated into a multi-modal molecular test. Citation Format: Corinna Keup, Cornelia Kolberg-Liedtke, Song Tian, Samuel J. Rulli, Siegfried Hauch, Paul Buderath, Oliver Hoffmann, Rainer Kimmig, Sabine Kasimir-Bauer. T cell receptor diversity in buffy coat samples from subsets of breast and ovarian cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1173.

Towards eDNA informed biodiversity studies – Comparing water derived molecular taxa with traditional survey methods

Managing natural resources in a sustainable manner requires understanding the complexity of ecosystems and the species that are associated with the different parts of the ecosystem. Much of this knowledge is derived from traditional sampling methods (e.g., different types of trawls). The analysis of environmental DNA (eDNA) can provide increased knowledge, complementary to the traditional methods. In the present pilot study, we sampled eDNA from two geographical areas, north and west of Svalbard (NWS) and in the southwestern Barents Sea (SWBS). The combination of trawling, visual identification of mammals and eDNA collection facilitated a robust analysis of fish and marine mammal diversity and species composition. Through 12S MiFish metabarcoding of the eDNA samples, we found that incorporating eDNA data provided an additional level of information on both the diversity of fish and marine mammals in the study areas. By adding eDNA data to the trawl data, we found that richness increased from 32 to 49 fish taxa. Significant differences in diversity and composition of the fish communities were detected by eDNA between the two study areas. Considering degradation and dilution factors it is postulated that the results represent resident species to the Barents Sea and that long -transported DNA from other areas are less likely.

The archaeome in metaorganism research, with a focus on marine models and their bacteria-archaea interactions.

Metaorganism research contributes substantially to our understanding of the interaction between microbes and their hosts, as well as their co-evolution. Most research is currently focused on the bacterial community, while archaea often remain at the sidelines of metaorganism-related research. Here, we describe the archaeome of a total of eleven classical and emerging multicellular model organisms across the phylogenetic tree of life. To determine the microbial community composition of each host, we utilized a combination of archaea and bacteria-specific 16S rRNA gene amplicons. Members of the two prokaryotic domains were described regarding their community composition, diversity, and richness in each multicellular host. Moreover, association with specific hosts and possible interaction partners between the bacterial and archaeal communities were determined for the marine models. Our data show that the archaeome in marine hosts predominantly consists of Nitrosopumilaceae and Nanoarchaeota, which represent keystone taxa among the porifera. The presence of an archaeome in the terrestrial hosts varies substantially. With respect to abundant archaeal taxa, they harbor a higher proportion of methanoarchaea over the aquatic environment. We find that the archaeal community is much less diverse than its bacterial counterpart. Archaeal amplicon sequence variants are usually host-specific, suggesting adaptation through co-evolution with the host. While bacterial richness was higher in the aquatic than the terrestrial hosts, a significant difference in diversity and richness between these groups could not be observed in the archaeal dataset. Our data show a large proportion of unclassifiable archaeal taxa, highlighting the need for improved cultivation efforts and expanded databases.

Comparative Analysis of Healthy Gut Microbiota in German and Korean Populations: Insights from Large-Scale Cohort Studies

Healthy individuals often have different gut microbiota, and these differences can be influenced by their country of origin or their race. This study aimed to compare the gut microbiota compositions of healthy Germans and Koreans using 16S rRNA sequencing data extracted from public sources. Two cohorts, comprising 1592 samples (804 Germans and 788 Koreans), were analyzed for alpha and beta diversity, core microbiome, and abundances of specific taxa. The Prevotella enterotype was more prevalent in Koreans, and significant diversity differences were observed depending on cohorts and enterotypes. The core microbiomes across all enterotypes and cohorts included Bacteroides, Faecalibacterium, Parabacteroides, and Lachnospira. Several common core microbiomes were also found depending on enterotype. Koreans exhibited higher abundances of Faecalibacterium, Prevotella, and Bacteroides, while Germans had higher abundances of Blautia, Subdoligranulum, and Agathobacter. Distinctive microbiomes were identified by enterotype. The study enhances comprehension of gut microbiome variations linked to enterotype and geographical factors, and emphasizes the need for additional research to establish correlations between specific microbial properties and individual health status.

Study on the soil microbial community structure of the Rhizosphere of Camellia sinensis L. in Anping Village, Kaiyang County, Guizhou Province

BackgroundTo determine the differences in the microbial communities in the Camellia sinensis L. hairy root, lateral root, and main root rhizospheres in Anping Village, Kaiyang County, Guizhou Province, the community structure, diversity, and main dominant species of bacteria and fungi in different parts of the soil were analyzed by ITS and 16S sequencing.ResultsIn the rhizosphere soil of the main root, lateral root, and hairy root of Camellia sinensis L., there were significant differences in the diversity and richness of the bacterial and fungal communities. The bacterial diversity was the highest and the fungal richness was the lowest in the rhizosphere soil of the main root. In the bacterial community, Proteobacteria, Actinobacteria, Acidobacteria, Chloroflexi, and Gemmatimonadetes were the common dominant bacteria. Rhodospirillaceae, Bradyrhizobiaceae, Hyphomicrobiaceae, Solibacteraceae, and Koribacteraceae were the common dominant bacteria in the rhizosphere soil of different parts of the root system, but the relative abundance of bacteria in different parts of the rhizosphere soil varied greatly. The dominant groups of fungal communities in different parts of the rhizosphere soil were Basidiomycota, Ascomycota, Mortierellomycota, and Sebacinaceae. The structure of the fungal community is similar in different parts.ConclusionsCompared with the different parts of the hairy root, lateral root, and main root of rhizosphere soil of Camellia sinensis L. in Anping village, it was found that the abundance of fungal community decreased with the increase of bacterial community abundance, and there were significant differences in bacterial community diversity and structure. However, the fungal community maintained stability among different parts.

Kuntayhtiöiden hallitusten puheenjohtajien poliittinen tausta ja monimuotoisuus

The political background and diversity of MOC chairs Study examines whether the chairs of the board of Finnish municipally owned companies (MOCs) have political backgrounds and what their distribution by gender is. Specifically, the study aims to discover possible differences between the MOCs of the 21 largest Finnish cities (C21) and those owned by the smaller municipalities. By using agency theory, statistical methods, and a dataset of 1012 MOCs and political background of chairs, this study finds support for the hypothesis that the MOCs of C21 cities have less politically connected chairs than the MOCs of the smaller municipalities. 46,6 % have a chair with a political background. While the study discovers the share of female chairs to be rather small (16,7 %), there appears to be no significant difference in diversity between the MOCs of larger and smaller municipalities.

Gut Microbiome Profiling of the Endangered Southern Greater Glider (Petauroides volans) after the 2019-2020 Australian Megafire.

Studying the gut microbiome can provide valuable insights into animal health and inform the conservation management of threatened wildlife. Gut microbiota play important roles in regulating mammalian host physiology, including digestion, energy metabolism and immunity. Dysbiosis can impair such physiological processes and compromise host health, so it is essential that the gut microbiome be considered in conservation planning. The southern greater glider (Petauroides volans) is an endangered arboreal marsupial that faced widespread habitat fragmentation and population declines following the 2019-2020 Australian bushfire season. This study details baseline data on the gut microbiome of this species. The V3-V4 region of the 16S rRNA gene was amplified from scats collected from individuals inhabiting burnt and unburnt sites across southeastern Australia and sequenced to determine bacterial community composition. Southern greater glider gut microbiomes were characterised by high relative abundances of Firmicutes and Bacteroidota, which is consistent with that reported for other marsupial herbivores. Significant differences in gut microbial diversity and community structure were detected among individuals from different geographic locations. Certain microbiota and functional orthologues were also found to be significantly differentially abundant between locations. The role of wildfire in shaping southern greater glider gut microbiomes was shown, with some significant differences in the diversity and abundance of microbiota detected between burnt and unburnt sites. Overall, this study details the first data on greater glider (Petauroides) gut microbiomes, laying the foundation for future studies to further explore relationships between microbial community structure, environmental stressors and host health.

Aquatic phases have a stronger effect on lotic benthic diatoms than human-induced microhabitat variability

AbstractHere, we studied the influence of changes of aquatic phases (standing and flowing phases) and human-induced habitat variability (natural and artificial) on the composition and diversity of benthic diatom assemblages in a small lowland stream in the Pannonian Ecoregion. Significant differences in composition were hypothesized between phases and habitats. Lower diversity was hypothesized in the flowing phase and in the artificial habitat. In addition, worser ecological status were assumed in the artificial habitat and in the standing phase than in the others. Our results only partially supported our hypotheses. While there was no significant difference in the composition of the assemblages between the natural and concreted habitats, the alteration in flow conditions resulted in a significant change. No significant differences in diversity were found between aquatic phases. In contrast, biodiversity was higher in the artificial habitat than in the natural one. While the anthropogenic impact, i.e., concreted streambed has no significant influence on diatom-based ecological status, values of diatom indices were significantly higher in the flowing phase. Our results highlight that extreme weather events play a major role in shaping diatom assemblages even during a short period, which should be taken into account in water management and nature conservation measures.

Effects of a short-term temperature increase on arthropod communities associated with pastures.

The impact of climate change on islands is expected to cause dramatic consequences on native biodiversity. However, limited data are available for arthropod communities in island agroecosystems. In this study, we simulate a small-scale climatic change (average of +1.2°C), using Open Top Chambers (OTCs) in forage crops in the Azores Archipelago (Portugal) and test the responses of arthropod communities associated with intensively-managed pastures. At three sites, twenty 1 x 1 m plots were established: 10 treatment plots with OTCs and 10 control plots. Arthropods were sampled with pitfall traps on two sampling events (winter and summer of 2020). When considering all species collected, arthropods' abundance was lower in OTCs. Specific taxa, namely spiders and beetles, showed a fast response to the OTCs' presence. The assemblage of non-indigenous spiders well adapted to pastures showed a significant difference in diversity with a slightly greater richness, but lower abundance inside the warmer plots. However, the presence of OTCs resulted in a decrease in beetle richness and abundance. This decline may be attributed to the multiple effects of warming. Therefore, it is imperative to conduct further investigations to elucidate the ecological processes that underlie the observed patterns.

Deep Isolated Aquifer Brines Harbor Atypical Halophilic Microbial Communities in Quebec, Canada.

The deep terrestrial subsurface, hundreds of meters to kilometers below the surface, is characterized by oligotrophic conditions, dark and often anoxic settings, with fluctuating pH, salinity, and water availability. Despite this, microbial populations are detected and active, contributing to biogeochemical cycles over geological time. Because it is extremely difficult to access the deep biosphere, little is known about the identity and metabolisms of these communities, although they likely possess unknown pathways and might interfere with deep waste deposits. Therefore, we analyzed rock and groundwater microbial communities from deep, isolated brine aquifers in two regions dating back to the Ordovician and Devonian, using amplicon and whole genome sequencing. We observed significant differences in diversity and community structure between both regions, suggesting an impact of site age and composition. The deep hypersaline groundwater did not contain typical halophilic bacteria, and genomes suggested pathways involved in protein and hydrocarbon degradation, and carbon fixation. We identified mainly one strategy to cope with osmotic stress: compatible solute uptake and biosynthesis. Finally, we detected many bacteriophage families, potentially indicating that bacteria are infected. However, we also found auxiliary metabolic genes in the viral genomes, probably conferring an advantage to the infected hosts.

Exploring the Influence of Small-Scale Geographical and Seasonal Variations Over the Microbial Diversity in a Poly-extreme Athalosaline Wetland

Microorganisms are the most diverse life form on the planet and are critical for maintaining the geochemical cycles, especially in extreme environments. Bacterial communities are dynamic and respond directly to changes in abiotic conditions; among these communities, poly-extremophiles are particularly sensitive to perturbations due to their high specialization. Salar de Huasco is a high-altitude wetland located on the Chilean Altiplano exhibiting several conditions considered extreme for life, including negative water balance, extreme variations in temperature and pH values, high UV radiation, and the presence of various toxic metal(oids). However, previous reports have revealed a diverse bacterial community that has adapted to these conditions, here, we aimed to determine whether microbial community diversity and composition changed in response to geographical and seasonal variations. We found that there are significant differences in diversity, abundance, and composition in bacterial taxa that could be attributed to local geographical and seasonal variations, which in turn, can be associated with microbial traits. In conclusion, in this poly-extreme environment, small-scale changes can trigger significant changes in the microbial communities that maintain basic biogeochemical cycles. Further in depth analysis of microbial functionality and geo-ecological dynamics are necessary to better understand the relationships between seasonal changes and bacterial communities.

Assessment of the differential profile of breast intratumoral bacteria in treatment responders and nonresponders.

580 Background: Despite improvements in breast cancer therapy, many patients do not respond to treatment: the response rate varies between 31 and 80% [Walks et al., 2019]. The tumor microenvironment contains a microbiome which is both cancer type-specific and different to surrounding normal tissue [Nejman et al., 2020]. It plays an important role in tumour microenvironment crosstalk with tumor cells and has been implicated in disease pathogenesis, being recognised in the latest hallmarks of cancer [Hanahan et Weinberg, 2011]. It has also successfully predicted treatment response [Chen et al., 2022; Hermida et al., 2022]. Here, we use conventional microbiome analysis alongside our proprietary mechanistically-powered technology platform to compare the intratumoral bacteria between responders and non-responders. We hypothesise that there are significant differences between those groups regarding composition and mechanistic function of the bacteria. Methods: The tumor microbiome can be deduced from existing sequencing data of tumor biopsy samples. Using 34 tumor DNA samples from 5 breast cancer studies, we compared the intratumoral bacterial profiles of responders to non-responders of various treatments. We performed microbiome analysis in R, including alpha diversity, compositional abundance profiles, and PERMANOVA (permutational analysis of variance). Additionally, BioCorteX CarbonMirror version dated 2023-02-14 was used to infer mechanistic links between bacterial species and the up- and downregulation of genes implicated in the hallmarks of cancer. Results: The results show significant differences in diversity and compositional profile between responders and non-responders: Non-responders have significantly higher alpha diversity ( p&lt;0.05) and a higher proportion of Proteobacteria. PERMANOVA analysis revealed that while responders are more likely to have commensal bacteria, non-responder tumour microbiomes are more likely to harbor pathogenic species such as Mycoplasmopsis fermentans. Mechanistic analysis showed that for all responders the tumor microbiome is consistently promoting tumor suppressor genes and downregulating proto-oncogenes. In non-responders, however, the tumor microbiome is upregulating and downregulating both with unclear consistency. Conclusions: Our results show microbiome differences between responders and non-responders which were mechanistically implicated in tumor pathogenesis. Further analysis divided by the hallmarks of cancer is required to fully understand the non-responder microbiome links. The reported findings could make the tumor microbiome a useful biomarker aiding patient stratification for both prognosis and treatment choice. They also highlight a potentially meaningful mechanistic link between tumour microenvironment and treatment response that could be leveraged as a novel therapeutic avenue.