Search Results (489)

The interaction between bacteria and fungi is one of the key interactions of microbial ecology, including mutualism, antagonism, and competition, which profoundly affects the balance and functions of animal microbial ecosystems. This article reviews the interactive dynamics of bacteria and fungi in more concerned microenvironments in animals, such as gut, rumen, and skin. Moreover, we summarize the molecular mechanisms and ecological functions of the interaction between bacteria and fungi. Three major bacterial–fungal interactions (mutualism, antagonism, and competition) are deeply discussed. Understanding of the interactions between bacteria and fungi allows us to understand, modulate, and maintain the community structure and functions. Furthermore, this summarization will provide a comprehensive perspective on animal production and veterinary medicine, as well as guide future research directions. Full article

Polymicrobial biofilms involving fungal and bacterial species are increasingly recognized as contributors to persistent infections, particularly in the oral cavity. Candida albicans and Aggregatibacter actinomycetemcomitans are two commensals that can turn into opportunistic pathogens and are able to form robust biofilms. Objectives: This study aimed to assess the interaction dynamics between these two microorganisms and to evaluate their susceptibility to fluconazole and azithromycin in single- and mixed-species forms. Methods: Biofilm biomass was quantified using crystal violet assays, while biofilm cell viability was assessed through CFU enumeration (biofilm viability assay). To assess the resistance properties of single versus mixed-species coincubations, we applied the antimicrobial susceptibility test (AST) to each drug, and analysed spatial organization with confocal laser scanning microscopy, using PNA-FISH. Results: The results indicated that both species can coexist without significant mutual inhibition. However, a non-reciprocal synergism was also observed, whereby mixed-species biofilm conditions promoted the growth of A. actinomycetemcomitans, while C. albicans growth remained stable. As expected, antimicrobial tolerance was elevated in mixed cultures, likely due to enhanced extracellular matrix production and potential quorum-sensing interactions, contributing to increased resistance against azithromycin and fluconazole. Conclusions: This study provides novel insights into previously rarely explored interactions between C. albicans and A. actinomycetemcomitans. These findings underscore the importance of investigating interspecies interactions within polymicrobial biofilms, as understanding their mechanisms, such as quorum-sensing molecules and metabolic cooperation, can contribute to improved diagnostics and more effective targeted therapeutic strategies against polymicrobial infections. Full article

The improvement in yield in cultivar mixtures has been well established. Despite increasing knowledge of the improvement involving within-species diversification and resource use efficiency, little is known about the benefits arising from relatedness-mediated intraspecific interactions in cultivar mixtures. This study used a relatedness gradient of rice cultivars to test whether neighbor relatedness contributes to improvements in grain yields in cultivar mixtures. We experimentally demonstrated the grain yield of rice cultivar mixtures with varying genetic relatedness under both field and controlled conditions. As a result, a closely related cultivar mixture had increased grain yield compared to monoculture and distantly related mixtures by optimizing the root-to-shoot ratio and accelerating flowering. The benefits over monoculture were most pronounced when compared to the significant yield reductions observed in distantly related mixtures. The relatedness-mediated improvement in yields depended on soil volume and nitrogen use level, with effects attenuating under larger soil volumes or nitrogen deficiency. Furthermore, neighbor relatedness enhanced the richness and diversity of both bacterial and fungal communities in the rhizosphere soil, leading to a significant restructuring of the microbial community composition. These findings suggest that neighbor relatedness may improve the grain yield of rice cultivar mixtures. Beneficial plant–plant interactions may be generated by manipulating cultivar kinship within a crop species. A thorough understanding of kinship strategies in cultivar mixtures offers promising prospects for increasing crop production. Full article

A simple and rapid precipitation process was successfully employed to prepare silver phosphate (SP, Ag₃PO₄). Two different phosphate sources: diammonium hydrogen phosphate ((NH₄)₂HPO₄) and dipotassium hydrogen phosphate (K₂HPO₄) were applied separately as the precursor, obtaining ((NH₄)₂HPO₄)⁻ and K₂HPO₄⁻ derived SP powders, named SP-A or SP-P, respectively. Fourier transform infrared (FTIR) spectra pointed out the vibrational characteristics of P–O and O–P–O interactions, confirming the presence of the PO43– functional group for SP. X-ray diffraction (XRD) patterns revealed that the SP crystallized in a cubic crystal structure. Whereas the field emission scanning electron microscope (FESEM) exposed spherical SP particles. The potentially antibacterial activity of SP-A and SP-P against bacterial Bacillus stratosphericus, yeast Meyerozyma guilliermondii, and fungal Phanerodontia chrysosporium was subsequently investigated. All studied microorganisms were recovered and isolated from the aquatic plant during the tissue culture process. The preliminary result of the antimicrobial test revealed that SP-A has higher antimicrobial activity than SP-P. The superior antimicrobial efficiency of SP-A compared to SP-P may be attributed to its purity and crystallite size, which provide a higher surface area and more active sites. In addition, the presence of potassium-related impurities in SP-P could have negatively affected its antimicrobial performance. These findings suggest that SP holds potential as an antimicrobial agent for maintaining sterility in tissue cultures, particularly in aquatic plant systems. The growth of both B. stratosphericus and M. guilliermondii was suppressed effectively at 30 ppm SP-A, whereas 10 ppm of SP-A can suppress P. chrysosporium development. This present work also highlights the potential of SP at very low concentrations (10–30 ppm) for utilization as an effective antimicrobial agent in tissue culture, compared to a commercial antimicrobial agent, viz., acetic acid, at the same concentration. Full article

Background: Salivary pH plays a critical role in oral health by influencing enamel demineralization, buffering capacity, and the ecology of oral microbiota. Essential oils such as Origanum vulgare (oregano) possess well-documented antimicrobial properties that may reduce acidogenic bacterial activity. However, the effects of edible delivery systems like jellies on salivary pH modulation and their potential interactions with hormonal states remain poorly understood. Methods: This study evaluated the in vitro antimicrobial activity of an oregano-oil-based jelly formulation against standard bacterial (Staphylococcus aureus, Streptococcus pyogenes, and Escherichia coli) and fungal (Candida albicans) strains using the Kirby–Bauer disc diffusion method. Additionally, a human trial (n = 91) measured salivary pH before and after administration of the oregano-oil jelly. Participants were characterized by age, smoking status, menopausal status, and presence of menstruation. Multiple linear regression was used to identify predictors of final salivary pH. Results: The oregano-oil jelly demonstrated strong in vitro antimicrobial activity, with inhibition zones up to 8 mm for E. coli and C. albicans. In vivo, mean unstimulated salivary pH increased from 6.94 to 7.07 overall, indicating a mild alkalinizing effect. However, menstruating participants showed a significant decrease in final pH (from 7.03 to 6.78). Multiple regression identified menstruation as a significant negative predictor (β = −0.377, p < 0.001) and initial pH as a positive predictor (β = +0.275, p = 0.002). Menopausal status was not a significant predictor, likely due to the small sample size. Conclusions: Oregano-oil jellies may represent a promising natural approach to support oral health by increasing salivary pH and providing strong antimicrobial activity. However, physiological states such as menstruation can significantly modulate this response, underscoring the importance of personalized or phase-aware oral care strategies. Further studies with larger, diverse cohorts and controlled hormonal assessments are needed to validate these findings and optimize product formulations. Full article

The human skin microbiota, a complex community of bacterial, fungal, and viral organisms, plays a crucial role in maintaining skin homeostasis and regulating host-pathogen interactions. Dysbiosis within this microbial ecosystem has been implicated in various dermatological conditions, including acne vulgaris, psoriasis, seborrheic dermatitis, and atopic dermatitis. This review, for the first time, provides recent advancements in all four layers of omic technologies—metagenomics, metatranscriptomics, metaproteomics, and metabolomics—offering comprehensive insights into microbial diversity, in the context of functional skin modeling. Thus, this review explores the application of these omic tools to in vitro skin models, providing an integrated framework for understanding the molecular mechanisms underlying skin–microbiota interactions in both healthy and pathological contexts. We highlight the importance of developing advanced in vitro skin models, including the integration of immune components and endothelial cells, to accurately replicate the cutaneous microenvironment. Moreover, we discuss the potential of these models to identify novel therapeutic targets, enabling the design of personalized treatments aimed at restoring microbial balance, reinforcing the skin barrier, and modulating inflammation. As the field progresses, the incorporation of multi-omic approaches into skin-microbiome research will be pivotal in unraveling the complex interactions between host and microbiota, ultimately advancing therapeutic strategies for skin-related diseases. Full article

The fungal component of microbiota, known as the mycobiome, inhabits different body niches such as the skin and the gastrointestinal, respiratory, and genitourinary tracts. Much information has been gained on the bacterial component of the human microbiota, but the mycobiome has remained somewhat elusive due to its sparsity, variability, susceptibility to environmental factors (e.g., early life colonization, diet, or pharmacological treatments), and the specific in vitro culture challenges. Functionally, the mycobiome is known to play a role in modulating innate and adaptive immune responses by interacting with microorganisms and immune cells. The latter elicits anti-fungal responses via the recognition of specific fungal cell-wall components (e.g., β-1,3-glucan, mannan, and chitin) by immune system receptors. These receptors then regulate the activation and differentiation of many innate and adaptive immune cells including mucocutaneous cell barriers, macrophages, neutrophils, dendritic cells, natural killer cells, innate-like lymphoid cells, and T and B lymphocytes. Mycobiome disruptions have been correlated with various diseases affecting mostly the brain, lungs, liver and pancreas. This work reviews our current knowledge on the mycobiome, focusing on its composition, research challenges, conditioning factors, interactions with the bacteriome and the immune system, and the known mycobiome alterations associated with disease. Full article

To investigate the characteristics of rhizosphere soil microbial communities associated with Schisandra sphenanthera across different altitudinal gradients and to reveal the driving factors of microbial community dynamics, this study collected rhizosphere soil samples at four elevations: 900 m (HB1), 1100 m (HB2), 1300 m (HB3), and 1500 m (HB4). High-throughput sequencing and molecular ecological network analysis were employed to analyze the microbial community composition and species interactions. A null model was applied to elucidate community assembly mechanisms. The results demonstrated that bacterial communities were dominated by Proteobacteria, Acidobacteriota, Actinobacteriota, and Chloroflexi. The relative abundance of Proteobacteria increased with elevation, while that of Acidobacteriota and Actinobacteriota declined. Fungal communities were primarily composed of Ascomycota and Basidiomycota, with both showing elevated relative abundances at higher altitudes. Diversity indices revealed that HB2 exhibited the highest bacterial Chao, Ace, and Shannon indices but the lowest Simpson index. For fungi, HB3 displayed the highest Chao and Ace indices, whereas HB4 showed the highest Shannon index and the lowest Simpson index. Ecological network analysis indicated stronger bacterial competition at lower elevations and enhanced cooperation at higher elevations, contrasting with fungal communities that exhibited increased competition at higher altitudes. Altitude and soil nutrients were negatively correlated with soil carbon content, while plant nutrients and fungal diversity positively correlated with soil carbon. Null model analysis suggested that deterministic processes dominated bacterial community assembly, whereas stochastic processes governed fungal assembly. These findings highlight significant altitudinal shifts in the microbial community structure and assembly mechanisms in S. sphenanthera rhizosphere soils, driven by the synergistic effects of soil nutrients, plant growth, and fungal diversity. This study provides critical insights into microbial ecology and carbon cycling in alpine ecosystems, offering a scientific basis for ecosystem management and conservation. Full article

Almond decline and dieback have become significant challenges in newly established orchards, with symptoms including internal necrosis, canker, and external gummosis. This work aims to explore the potential fungal and bacterial causative agents through metabarcoding and traditional culture plate isolation across six almond cultivars. Our results emphasize the multifactorial nature of almond decline and dieback, with possible co-infections by opportunistic fungi and bacteria playing a central role. Classical isolation identified 47 fungal species or genera, including Diaporthe amygdali, Diplodia corticola, Phytophthora sp., and several Fusarium species. Almond metabarcoding revealed a more diverse microbial community, highlighting the prevalence of soilborne pathogens such as Neocosmospora rubicola, Dactylonectria estremocensis, and Plectosphaerella niemeijerarum. Soil metabarcoding suggested that these pathogens likely originate from nursery substrates or soils shared with other crops, such as olives and vineyards, that serve as a source of inoculum. ‘Soleta’ generally presented lower richness when compared to the other tested cultivars, suggesting a higher degree of biotic stress and decreased plant resilience. This study highlights the value of integrating NGS approaches to comprehensively study complex diseases and the need for further research on pathogen interactions and cultivar susceptibility for the future development of new sustainable, targeted management strategies in almond orchards. Full article

The domestication process not only reduced the allelic diversity of tomato genotypes but also affected the genetic traits associated to microbial recruitment, their composition, and their diversity in different compartments of the plant host. Additionally, this process included the transition from natural to agricultural soils, which differ in nutrient availability, physicochemical properties, and agricultural practices. Therefore, modern cultivars may fail to recruit microbial taxa beneficial to their wild relatives, potentially losing important ecological functions. In this study, we analyzed the phylogenetic relationship and the rhizosphere microbiota of four tomato genotypes, Solanum chilense (wild species), S. lycopersicum var. cerasiforme (Cherry tomato), and the S. lycopersicum landrace ‘Poncho Negro’ and the modern cultivar ‘Cal Ace’, grown in both natural and agricultural soils. Microbial communities were identified using 16S rRNA (bacteria) and ITS2 (fungi) amplicon sequencing, allowing cross-domain taxonomic characterization. While the soil type was the main driver of overall microbial diversity, the host genotype influenced the recruitment of specific microbial taxa, which exhibited different recruitment patterns according to the genetic diversification of Solanum genotypes and soil types. Additionally, co-occurrence network analysis identified two main clusters: first, taxa did not show any preferential associations to particular genotypes or soil types, while the second cluster revealed specific microbial patterns associated to fungal taxa in natural soil and bacterial taxa in agricultural soil. Finally, the functional analysis suggested the loss of specific functions through tomato domestication independently of soil type. These findings highlight the role of the plant genotype as a fine-tuning factor in microbiome assembly, with implications for breeding strategies aimed at restoring beneficial plant–microbe interactions. Full article

Potato early dying disease complex (PED) leads to premature senescence and rapid decline in potato plants. Unlike potato wilt caused solely by Verticillium species, PED symptoms are more severe due to the synergistic effects of multiple pathogens, including root-lesion nematodes, fungi such as Colletotrichum and Fusarium, and soft-rot bacteria. To investigate the microbiome responsible for PED, soil and stem samples from healthy-looking and symptomatic plants were analyzed using amplicon-targeted next-generation sequencing (Illumina MiSeq and PacBio technologies). Samples were collected from four locations in New Brunswick, Canada from fields previously rotated with barley or oat. Comparative analysis of the bacterial, fungal, and eukaryotic diversity in soil samples showed minimal differences, with only bacterial alpha diversity influenced by the plant health status. Verticillium dahliae was abundant in all soil samples, and its abundance was significantly higher in the stems of diseased plants. Additional fungal species implicated in PED, including Plectosphaerella cucumerina, Colletotrichum coccodes, Botrytis sp., and Alternaria alternata, were also identified in the stems. This study highlights the complex, plant-associated microbial interactions underlying PED and provides a foundation for microbiome-informed disease management strategies. Full article

Lagochilascariasis is a neglected zoonotic helminthiasis, caused by Lagochilascaris minor, characterized by a complex and not well understood transmission cycle. This parasitic disease is endemic to Latin America, particularly Brazil, and is associated with rural and forested areas, where humans may serve as accidental hosts. The southeastern region of Pará state reports the highest number of cases, highlighting its epidemiological significance. Wildlife species, especially carnivores and rodents, play crucial roles as definitive and intermediate hosts, respectively. Although lagochilascariasis can lead to severe clinical manifestations, including chronic soft tissue infections and potential central nervous system involvement, it is likely underdiagnosed due to its similarity to fungal and bacterial diseases. The anthropization of the Amazon Biome, through deforestation and habitat fragmentation, coupled with increased human–wildlife interactions, may be influencing the epidemiology of this parasitosis. This review aims to summarize current knowledge of L. minor transmission routes, the role of wildlife in maintaining its cycle, and the impact of environmental changes on disease patterns. Such insights are vital for One Health strategies, which integrate human, animal, and environmental health approaches to mitigate the disease burden. Full article

Glycans on the surface of all immune cells are the product of diverse post-translational modifications (glycosylation) that affect almost all proteins and possess enormous structural heterogeneity. Their bioinformational content is decoded by glycan-binding proteins (lectins, GBPs), such as C-type lectins, including selectins, galectins, and Siglecs. Glycans located on the surface of immune cells are involved in many immunological processes through interactions with GBPs. Lectins recognize changes in the glycan epitopes; distinguish among host (self), microbial (non-self), and tumor (modified self) antigens; and consequently regulate immune responses. Understanding GBP–glycan interactions accelerates the development of glycan-targeted therapeutics in severe diseases, including inflammatory and autoimmune diseases and cancer. This review will discuss N- and O-glycosylations and glycosyltransferases involved in the biosynthesis of carbohydrate epitopes and address how interactions between glycan epitopes and GBPs are crucial in immune responses. The pivotal role of the glycan antigen tetrasaccharide sialyl Lewis x in mediating immune and tumor cell trafficking into the extravascular site will be discussed. Next, the role of glycans in modulating bacterial, fungal, viral, and parasitic infections and cancer will be surveyed. Finally, the role of glycosylation in antibodies and carbohydrate vaccines will be analyzed. Full article

Engineering disturbances are increasing in permafrost regions of northeastern China, where soil microorganisms play essential roles in biogeochemical cycling and are highly sensitive to linear infrastructure disturbances. However, limited research has addressed how microbial communities respond to different post-engineering-disturbance recovery stages. This study investigated the impacts of the China–Russia Crude Oil Pipelines (CRCOPs) on soil microbial communities in a typical boreal forest permafrost zone of the Da Xing’anling Mountains. Soil samples were collected from undisturbed forest (the control, CK); short-term disturbed sites associated with Pipeline II, which was constructed in 2018 (SD); and long-term disturbed sites associated with Pipeline I, which was constructed in 2011 (LD). Pipeline engineering disturbances significantly increased soil clay content and pH while reducing soil water content (SWC), soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) (p < 0.05). No significant differences in these soil properties were observed between SD and LD. Bacterial diversity increased significantly, whereas fungal diversity significantly decreased following pipeline disturbances (p < 0.05). The beta diversity of both bacterial and fungal communities differed significantly among the three disturbance types. At the phylum level, pipeline disturbance increased the relative abundances of Proteobacteria, Acidobacteriota, Actinobacteriota, Ascomycota, and Mortierellomycota while reducing those of Bacteroidota and Basidiomycota. These shifts were associated with disturbance-induced changes in soil properties. Microbial co-occurrence networks in SD exhibited greater complexity and connectivity than those in CK and LD, suggesting intensified biotic interactions and active ecological reassembly during the early recovery phase. These findings suggest that pipeline disturbance could drive soil microbial systems into a new stable state that is difficult to restore over the long term, highlighting the profound impacts of linear infrastructure on microbial ecological functions in cold regions. This study provides a scientific basis for ecological restoration and biodiversity conservation in permafrost-affected areas. Full article

The Qinghai–Tibet Plateau is a key region for biodiversity conservation, where alpine grasslands are ecologically important. While previous studies have mainly addressed vegetation, ecosystem processes, and soil microbes, phyllosphere microorganisms are essential for nutrient cycling, plant health, and stress tolerance. However, their communities remain poorly understood compared to those in soil. The relative influence of host identity and environmental conditions on shaping phyllosphere microbial diversity and community assembly remains uncertain. In this study, we characterized phyllosphere bacterial and fungal communities of the phyllosphere at two alpine steppe sites with similar vegetation but climatic conditions: the Qilian Mountains (QLM) and the Qinghai Lake region (LQS). At both sites, Cyanobacteriota and Ascomycota were the predominant bacterial and fungal taxa, respectively. Microbial α-diversity did not differ significantly between the two regions, implying that host-associated mechanisms may stabilize within-site diversity. In contrast, β-diversity exhibited clear spatial differentiation. In QLM, bacterial β-diversity was significantly correlated with mean annual precipitation, while fungal α- and β-diversity were associated with soil nutrient levels (including nitrate, ammonium, available potassium, and phosphorus) and vegetation coverage. At LQS, the β-diversity of both bacterial and fungal communities was strongly influenced by soil electrical conductivity, and fungal communities were further shaped by vegetation cover. Community assembly processes were predominantly stochastic at both sites, although deterministic patterns were more pronounced in QLM. Variability in moisture availability contributed to random bacterial assembly at LQS, while increased environmental heterogeneity promoted deterministic assembly in fungal communities. The elevated diversity of microbes and plants in QLM also reinforced deterministic processes. Overall, our findings support a host–environment interaction hypothesis, indicating that host factors primarily govern α-diversity, while climatic and soil-related variables have stronger effects on β-diversity and microbial assembly dynamics. These insights advance our understanding of how phyllosphere microbial communities may respond to environmental change in alpine ecosystems. Full article