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2.
Bull Exp Biol Med ; 177(1): 84-87, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38960954

RESUMO

A cultural microbiological study of the vaginal microbiota of patients of reproductive age was carried out to isolate the species Lactobacillus iners with subsequent study of phenotypic features. The presence of two phenotypically different species variants was found in patients with bacterial vaginosis.


Assuntos
Lactobacillus , Vagina , Vaginose Bacteriana , Humanos , Feminino , Lactobacillus/isolamento & purificação , Lactobacillus/classificação , Vaginose Bacteriana/microbiologia , Vagina/microbiologia , Adulto , Microbiota/fisiologia , Adulto Jovem , RNA Ribossômico 16S/genética
3.
Bull Exp Biol Med ; 177(1): 140-146, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38960962

RESUMO

The dynamics of lung microbiota in tuberculosis remains poorly understood. Sequencing of variable regions of the 16S rRNA gene from surgically excised tuberculosis foci and biopsy specimens of normal lung tissue allowed characterization of the diversity and predictive potential of bacterial communities. Taxonomic diversity indices attested to differences in the structure of microbial communities between "healthy" lungs and tuberculomas. The microbial composition of "healthy" lungs varied in taxonomic diversity and was presented by both gram-positive and gram-negative bacteria with sufficiently similar metabolic potential. The microbiota of the examined tuberculomas consisted of Mycobacterium tuberculosis in 99.9% of cases. A significant part of the metabolic pathways predicted by PICRUSt2 included cholesterol catabolism, sulfate assimilation, and various pathways for the biosynthesis of cell wall components.


Assuntos
Pulmão , Mycobacterium tuberculosis , RNA Ribossômico 16S , Tuberculoma , Humanos , RNA Ribossômico 16S/genética , Mycobacterium tuberculosis/genética , Tuberculoma/microbiologia , Tuberculoma/patologia , Tuberculoma/genética , Pulmão/microbiologia , Pulmão/patologia , Pulmão/metabolismo , Microbiota/genética , Microbiota/fisiologia , Masculino , Adulto , Tuberculose Pulmonar/microbiologia , Feminino , Pessoa de Meia-Idade , Bactérias Gram-Negativas/genética , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/metabolismo , Bactérias Gram-Positivas/classificação
4.
Nat Commun ; 15(1): 5866, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997249

RESUMO

The estuarine plastisphere, a novel ecological habitat in the Anthropocene, has garnered global concerns. Recent geochemical evidence has pointed out its potential role in influencing nitrogen biogeochemistry. However, the biogeochemical significance of the plastisphere and its mechanisms regulating nitrogen cycling remain elusive. Using 15N- and 13C-labelling coupled with metagenomics and metatranscriptomics, here we unveil that the plastisphere likely acts as an underappreciated nitrifying niche in estuarine ecosystems, exhibiting a 0.9 ~ 12-fold higher activity of bacteria-mediated nitrification compared to surrounding seawater and other biofilms (stone, wood and glass biofilms). The shift of active nitrifiers from O2-sensitive nitrifiers in the seawater to nitrifiers with versatile metabolisms in the plastisphere, combined with the potential interspecific cooperation of nitrifying substrate exchange observed among the plastisphere nitrifiers, collectively results in the unique nitrifying niche. Our findings highlight the plastisphere as an emerging nitrifying niche in estuarine environment, and deepen the mechanistic understanding of its contribution to marine biogeochemistry.


Assuntos
Bactérias , Biofilmes , Estuários , Nitrificação , Água do Mar , Água do Mar/microbiologia , Bactérias/metabolismo , Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Ecossistema , Microbiota/fisiologia , Metagenômica , Filogenia , Ciclo do Nitrogênio , Nitrogênio/metabolismo , Isótopos de Nitrogênio/metabolismo
5.
Food Res Int ; 188: 114497, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823877

RESUMO

The spontaneous Baijiu fermentation system harbors a complex microbiome that is highly dynamic in time and space and varies depending on the Jiuqu starters and environmental factors. The intricate microbiota presents in the fermentation environment is responsible for carrying out various reactions. These reactions necessitate the interaction among the core microbes to influence the community function, ultimately shaping the distinct Baijiu styles through the process of spontaneous fermentation. Numerous studies have been conducted to enhance our understanding of the diversity, succession, and function of microbial communities with the aim of improving fermentation manipulation. However, a comprehensive and critical assessment of the core microbes and their interaction remains one of the significant challenges in the Baijiu fermentation industry. This paper focuses on the fermentation properties of core microbes. We discuss the state of the art of microbial traceability, highlighting the crucial role of environmental and starter microbiota in the Baijiu brewing microbiome. Also, we discuss the various interactions between microbes in the Baijiu production system and propose a potential conceptual framework that involves constructing predictive network models to simplify and quantify microbial interactions using co-culture models. This approach offers effective strategies for understanding the core microbes and their interactions, thus beneficial for the management of microbiota and the regulation of interactions in Baijiu fermentation processes.


Assuntos
Fermentação , Microbiologia de Alimentos , Microbiota , Microbiota/fisiologia , Interações Microbianas/fisiologia , Cerveja/microbiologia , Bactérias/metabolismo , Bactérias/classificação
6.
Nat Commun ; 15(1): 4709, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830891

RESUMO

Microbial communities often exhibit more than one possible stable composition for the same set of external conditions. In the human microbiome, these persistent changes in species composition and abundance are associated with health and disease states, but the drivers of these alternative stable states remain unclear. Here we experimentally demonstrate that a cross-kingdom community, composed of six species relevant to the respiratory tract, displays four alternative stable states each dominated by a different species. In pairwise coculture, we observe widespread bistability among species pairs, providing a natural origin for the multistability of the full community. In contrast with the common association between bistability and antagonism, experiments reveal many positive interactions within and between community members. We find that multiple species display cooperative growth, and modeling predicts that this could drive the observed multistability within the community as well as non-canonical pairwise outcomes. A biochemical screening reveals that glutamate either reduces or eliminates cooperativity in the growth of several species, and we confirm that such supplementation reduces the extent of bistability across pairs and reduces multistability in the full community. Our findings provide a mechanistic explanation of how cooperative growth rather than competitive interactions can underlie multistability in microbial communities.


Assuntos
Interações Microbianas , Microbiota , Microbiota/fisiologia , Humanos , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/crescimento & desenvolvimento , Ácido Glutâmico/metabolismo , Modelos Biológicos , Técnicas de Cocultura
7.
PLoS Comput Biol ; 20(6): e1012196, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38875277

RESUMO

Time series studies of microbiome interventions provide valuable data about microbial ecosystem structure. Unfortunately, existing models of microbial community dynamics have limited temporal memory and expressivity, relying on Markov or linearity assumptions. To address this, we introduce a new class of models based on transfer functions. These models learn impulse responses, capturing the potentially delayed effects of environmental changes on the microbial community. This allows us to simulate trajectories under hypothetical interventions and select significantly perturbed taxa with False Discovery Rate guarantees. Through simulations, we show that our approach effectively reduces forecasting errors compared to strong baselines and accurately pinpoints taxa of interest. Our case studies highlight the interpretability of the resulting differential response trajectories. An R package, mbtransfer, and notebooks to replicate the simulation and case studies are provided.


Assuntos
Biologia Computacional , Microbiota , Microbiota/fisiologia , Humanos , Biologia Computacional/métodos , Simulação por Computador , Modelos Biológicos , Software , Cadeias de Markov
8.
PeerJ ; 12: e17421, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827308

RESUMO

Background: Rainfall-induced coastal runoff represents an important environmental impact in near-shore coral reefs that may affect coral-associated bacterial microbiomes. Shifts in microbiome community composition and function can stress corals and ultimately cause mortality and reef declines. Impacts of environmental stress may be site specific and differ between coral microbiome compartments (e.g., tissue versus mucus). Coastal runoff and associated water pollution represent a major stressor for near-shore reef-ecosystems in Guam, Micronesia. Methods: Acropora pulchra colonies growing on the West Hagåtña reef flat in Guam were sampled over a period of 8 months spanning the 2021 wet and dry seasons. To examine bacterial microbiome diversity and composition, samples of A. pulchra tissue and mucus were collected during late April, early July, late September, and at the end of December. Samples were collected from populations in two different habitat zones, near the reef crest (farshore) and close to shore (nearshore). Seawater samples were collected during the same time period to evaluate microbiome dynamics of the waters surrounding coral colonies. Tissue, mucus, and seawater microbiomes were characterized using 16S DNA metabarcoding in conjunction with Illumina sequencing. In addition, water samples were collected to determine fecal indicator bacteria (FIB) concentrations as an indicator of water pollution. Water temperatures were recorded using data loggers and precipitation data obtained from a nearby rain gauge. The correlation structure of environmental parameters (temperature and rainfall), FIB concentrations, and A. pulchra microbiome diversity was evaluated using a structural equation model. Beta diversity analyses were used to investigate spatio-temporal trends of microbiome composition. Results: Acropora pulchra microbiome diversity differed between tissues and mucus, with mucus microbiome diversity being similar to the surrounding seawater. Rainfall and associated fluctuations of FIB concentrations were correlated with changes in tissue and mucus microbiomes, indicating their role as drivers of A. pulchra microbiome diversity. A. pulchra tissue microbiome composition remained relatively stable throughout dry and wet seasons; tissues were dominated by Endozoicomonadaceae, coral endosymbionts and putative indicators of coral health. In nearshore A. pulchra tissue microbiomes, Simkaniaceae, putative obligate coral endosymbionts, were more abundant than in A. pulchra colonies growing near the reef crest (farshore). A. pulchra mucus microbiomes were more diverse during the wet season than the dry season, a distinction that was also associated with drastic shifts in microbiome composition. This study highlights the seasonal dynamics of coral microbiomes and demonstrates that microbiome diversity and composition may differ between coral tissues and the surface mucus layer.


Assuntos
Antozoários , Recifes de Corais , Microbiota , Estações do Ano , Animais , Antozoários/microbiologia , Microbiota/fisiologia , Microbiota/genética , Muco/microbiologia , Água do Mar/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação
9.
Cell ; 187(12): 2905-2906, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848675

RESUMO

Microbial communities perform many important functions, such as carbon sequestration, decomposition, pathogen resistance, etc., but quantitatively predicting functions of new communities remains a major challenge. In this issue of Cell, Diaz-Colunga et al. report a new simple statistical regularity that enables such predictions.


Assuntos
Microbiologia Ambiental , Microbiota , Bactérias/metabolismo , Bactérias/genética , Microbiota/fisiologia , Modelos Biológicos
10.
Compr Rev Food Sci Food Saf ; 23(4): e13364, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38847746

RESUMO

Kefir milk, known for its high nutritional value and health benefits, is traditionally produced by fermenting milk with kefir grains. These grains are a complex symbiotic community of lactic acid bacteria, acetic acid bacteria, yeasts, and other microorganisms. However, the intricate coexistence mechanisms within these microbial colonies remain a mystery, posing challenges in predicting their biological and functional traits. This uncertainty often leads to variability in kefir milk's quality and safety. This review delves into the unique structural characteristics of kefir grains, particularly their distinctive hollow structure. We propose hypotheses on their formation, which appears to be influenced by the aggregation behaviors of the community members and their alliances. In kefir milk, a systematic colonization process is driven by metabolite release, orchestrating the spatiotemporal rearrangement of ecological niches. We place special emphasis on the dynamic spatiotemporal changes within the kefir microbial community. Spatially, we observe variations in species morphology and distribution across different locations within the grain structure. Temporally, the review highlights the succession patterns of the microbial community, shedding light on their evolving interactions.Furthermore, we explore the ecological mechanisms underpinning the formation of a stable community composition. The interplay of cooperative and competitive species within these microorganisms ensures a dynamic balance, contributing to the community's richness and stability. In kefir community, competitive species foster diversity and stability, whereas cooperative species bolster mutualistic symbiosis. By deepening our understanding of the behaviors of these complex microbial communities, we can pave the way for future advancements in the development and diversification of starter cultures for food fermentation processes.


Assuntos
Kefir , Simbiose , Kefir/microbiologia , Simbiose/fisiologia , Microbiota/fisiologia , Fermentação , Microbiologia de Alimentos
11.
Nat Commun ; 15(1): 5137, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879542

RESUMO

Unravelling the multifaceted and bidirectional interactions between microbiota and host physiology represents a major scientific challenge. Here, we utilise the nematode model, Pristionchus pacificus, coupled to a laboratory-simulated decay process of its insect host, to mimic natural microbiota succession and investigate associated tripartite interactions. Metagenomics reveal that during initial decay stages, the population of vitamin B-producing bacteria diminishes, potentially due to a preferential selection by nematodes. As decay progresses to nutrient-depleted stages, bacteria with smaller genomes producing less nutrients become more prevalent. Lipid utilisation and dauer formation, representing key nematode survival strategies, are influenced by microbiota changes. Additionally, horizontally acquired cellulases extend the nematodes' reproductive phase due to more efficient foraging. Lastly, the expressions of Pristionchus species-specific genes are more responsive to natural microbiota compared to conserved genes, suggesting their importance in the organisms' adaptation to its ecological niche. In summary, we show the importance of microbial successions and their reciprocal interaction with nematodes for insect decay in semi-artificial ecosystems.


Assuntos
Besouros , Ecossistema , Microbiota , Nematoides , Animais , Besouros/microbiologia , Besouros/fisiologia , Microbiota/fisiologia , Nematoides/microbiologia , Nematoides/fisiologia , Metagenômica , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Celulases/metabolismo , Celulases/genética
12.
Cell Host Microbe ; 32(6): 996-1010.e4, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38870906

RESUMO

The composition and maturation of the early-life microbiota are modulated by a number of perinatal factors, whose interplay in relation to microbial vertical transmission remains inadequately elucidated. Using recent strain-tracking methodologies, we analyzed mother-to-infant microbiota transmission in two different birth environments: hospital-born (vaginal/cesarean) and home-born (vaginal) infants and their mothers. While delivery mode primarily explains initial compositional differences, place of birth impacts transmission timing-being early in homebirths and delayed in cesarean deliveries. Transmission patterns vary greatly across species and birth groups, yet certain species, like Bifidobacterium longum, are consistently vertically transmitted regardless of delivery setting. Strain-level analysis of B. longum highlights relevant and consistent subspecies replacement patterns mainly explained by breastfeeding practices, which drive changes in human milk oligosaccharide (HMO) degrading capabilities. Our findings highlight how delivery setting, breastfeeding duration, and other lifestyle preferences collectively shape vertical transmission, impacting infant gut colonization during early life.


Assuntos
Aleitamento Materno , Leite Humano , Humanos , Feminino , Leite Humano/microbiologia , Recém-Nascido , Lactente , Microbioma Gastrointestinal/fisiologia , Microbiota/fisiologia , Adulto , Bifidobacterium , Transmissão Vertical de Doenças Infecciosas , Gravidez
15.
BMC Plant Biol ; 24(1): 546, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872113

RESUMO

BACKGROUND: Apple Replant Disease (ARD) is common in major apple-growing regions worldwide, but the role of rhizosphere microbiota in conferring ARD resistance and promoting plant growth remains unclear. RESULTS: In this study, a synthetic microbial community (SynCom) was developed to enhance apple plant growth and combat apple pathogens. Eight unique bacteria selected via microbial culture were used to construct the antagonistic synthetic community, which was then inoculated into apple seedlings in greenhouse experiments. Changes in the rhizomicroflora and the growth of aboveground plants were monitored. The eight strains, belonging to the genera Bacillus and Streptomyces, have the ability to antagonize pathogens such as Fusarium oxysporum, Rhizoctonia solani, Botryosphaeria ribis, and Physalospora piricola. Additionally, these eight strains can stably colonize in apple rhizosphere and some of them can produce siderophores, ACC deaminase, and IAA. Greenhouse experiments with Malus hupehensis Rehd indicated that SynCom promotes plant growth (5.23%) and increases the nutrient content of the soil, including soil organic matter (9.25%) and available K (1.99%), P (7.89%), and N (0.19%), and increases bacterial richness and the relative abundance of potentially beneficial bacteria. SynCom also increased the stability of the rhizosphere microbial community, the assembly of which was dominated by deterministic processes (|ß NTI| > 2). CONCLUSIONS: Our results provide insights into the contribution of the microbiome to pathogen inhibition and host growth. The formulation and manipulation of similar SynComs may be a beneficial strategy for promoting plant growth and controlling soil-borne disease.


Assuntos
Malus , Doenças das Plantas , Rizosfera , Malus/microbiologia , Malus/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Microbiologia do Solo , Microbiota/fisiologia , Rhizoctonia/fisiologia , Agentes de Controle Biológico , Bacillus/fisiologia , Antibiose
16.
Nat Commun ; 15(1): 5323, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909053

RESUMO

Bioethanol is a sustainable energy alternative and can contribute to global greenhouse-gas emission reductions by over 60%. Its industrial production faces various bottlenecks, including sub-optimal efficiency resulting from bacteria. Broad-spectrum removal of these contaminants results in negligible gains, suggesting that the process is shaped by ecological interactions within the microbial community. Here, we survey the microbiome across all process steps at two biorefineries, over three timepoints in a production season. Leveraging shotgun metagenomics and cultivation-based approaches, we identify beneficial bacteria and find improved outcome when yeast-to-bacteria ratios increase during fermentation. We provide a microbial gene catalogue which reveals bacteria-specific pathways associated with performance. We also show that Limosilactobacillus fermentum overgrowth lowers production, with one strain reducing yield by ~5% in laboratory fermentations, potentially due to its metabolite profile. Temperature is found to be a major driver for strain-level dynamics. Improved microbial management strategies could unlock environmental and economic gains in this US $ 60 billion industry enabling its wider adoption.


Assuntos
Bactérias , Etanol , Fermentação , Etanol/metabolismo , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Microbiota/fisiologia , Biocombustíveis , Metagenômica , Microbiologia Industrial/métodos , Temperatura
17.
Adv Gerontol ; 37(1-2): 144-148, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38944785

RESUMO

Research on the condition of the lungs in senile people is an urgent task. This is due to the fact that degenerative or age-associated changes in the respiratory system play an important role in the formation of senile asthenia syndrome and a decrease in the age-related viability of the body as a whole. CT-scans of patients aged 80-90 years were analyzed (n=31). Age-associated changes were evaluated: the presence of linear fibrosis, increased pulmonary pattern by the type of reticular (reticular) changes, the presence of gross fibrous reticular changes with cystic cavities and air bullae (by the type of «cellular lung¼), as well as the presence of pulmonary emphysema. Most naturally, senile people show changes characteristic of linear pulmonary fibrosis and emphysema. The progression of the process leads to diffuse reticular changes in the interalveolar and intersegmental septa and, in adverse cases, to the formation of gross changes in the type of «cellular lung¼. Fibro-emphysematous changes are significantly more common in men. A microbiological study of the microbiota of the lower respiratory tract in elderly people was also carried out (n=16). When studying the microbiocenosis of the lower respiratory tract in elderly people, the following data were obtained: resident microflora was found in 71% and clinically significant microorganisms were found in 29%.


Assuntos
Microbiota , Enfisema Pulmonar , Humanos , Idoso de 80 Anos ou mais , Masculino , Feminino , Enfisema Pulmonar/microbiologia , Enfisema Pulmonar/fisiopatologia , Enfisema Pulmonar/diagnóstico , Microbiota/fisiologia , Pulmão/microbiologia , Tomografia Computadorizada por Raios X/métodos , Fibrose Pulmonar/fisiopatologia , Fibrose Pulmonar/microbiologia , Fibrose Pulmonar/diagnóstico , Fibrose Pulmonar/etiologia , Envelhecimento/fisiologia
18.
Microbiol Spectr ; 12(7): e0052024, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38832787

RESUMO

Rice anaerobic fermentation is a significant source of greenhouse gas (GHG) emissions, and in order to efficiently utilize crop residue resources to reduce GHG emissions, rice straw anaerobic fermentation was regulated using lactic acid bacteria (LAB) inoculants (FG1 and TH14), grass medium (GM) to culture LAB, and Acremonim cellulolyticus (AC). Microbial community, GHG emission, dry matter (DM) loss, and anaerobic fermentation were analyzed using PacBio single-molecule real-time and anaerobic fermentation system. The epiphytic microbial diversity of fresh rice straw was extremely rich and contained certain nutrients and minerals. During ensiling, large amounts of GHG such as carbon dioxide are produced due to plant respiration, enzymatic hydrolysis reactions, and proliferation of aerobic bacteria, resulting in energy and DM loss. Addition of FG1, TH14, and AC alone improved anaerobic fermentation by decreasing pH and ammonia nitrogen content (P < 0.05) and increased lactic acid content (P < 0.05) when compared to the control, and GM showed the same additive effect as LAB inoculants. Microbial additives formed a co-occurrence microbial network system dominated by LAB, enhanced the biosynthesis of secondary metabolites, diversified the microbial metabolic environment and carbohydrate metabolic pathways, weakened the amino acid metabolic pathways, and made the anaerobic fermentation cleaner. This study is of great significance for the effective utilization of crop straw resources, the promotion of sustainable livestock production, and the reduction of GHG emissions.IMPORTANCETo effectively utilize crop by-product resources, we applied microbial additives to silage fermentation of fresh rice straw. Fresh rice straw is extremely rich in microbial diversity, which was significantly reduced after silage fermentation, and its nutrients were well preserved. Silage fermentation was improved by microbial additives, where the combination of cellulase and lactic acid bacteria acted as enzyme-bacteria synergists to promote lactic acid fermentation and inhibit the proliferation of harmful bacteria, such as protein degradation and gas production, thereby reducing GHG emissions and DM losses. The microbial additives accelerated the formation of a symbiotic microbial network system dominated by lactic acid bacteria, which regulated silage fermentation and improved microbial metabolic pathways for carbohydrates and amino acids, as well as biosynthesis of secondary metabolites.


Assuntos
Fermentação , Gases de Efeito Estufa , Oryza , Oryza/microbiologia , Oryza/metabolismo , Gases de Efeito Estufa/metabolismo , Anaerobiose , Produtos Agrícolas/microbiologia , Produtos Agrícolas/metabolismo , Lactobacillales/metabolismo , Microbiota/fisiologia , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Silagem/microbiologia
19.
PLoS Comput Biol ; 20(6): e1012233, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38900842

RESUMO

Microbial communities play fundamental roles in every complex ecosystem, such as soil, sea and the human body. The stability and diversity of the microbial community depend precisely on the composition of the microbiota. Any change in the composition of these communities affects microbial functions. An important goal of studying the interactions between species is to understand the behavior of microbes and their responses to perturbations. These interactions among species are mediated by the exchange of metabolites within microbial communities. We developed a computational model for the microbial community that has a separate compartment for exchanging metabolites. This model can predict possible metabolites that cause competition, commensalism, and mutual interactions between species within a microbial community. Our constraint-based community metabolic modeling approach provides insights to elucidate the pattern of metabolic interactions for each common metabolite between two microbes. To validate our approach, we used a toy model and a syntrophic co-culture of Desulfovibrio vulgaris and Methanococcus maripaludis, as well as another in co-culture between Geobacter sulfurreducens and Rhodoferax ferrireducens. For a more general evaluation, we applied our algorithm to the honeybee gut microbiome, composed of seven species, and the epiphyte strain Pantoea eucalypti 299R. The epiphyte strain Pe299R has been previously studied and cultured with six different phyllosphere bacteria. Our algorithm successfully predicts metabolites, which imply mutualistic, competitive, or commensal interactions. In contrast to OptCom, MRO, and MICOM algorithms, our COMMA algorithm shows that the potential for competitive interactions between an epiphytic species and Pe299R is not significant. These results are consistent with the experimental measurements of population density and reproductive success of the Pe299R strain.


Assuntos
Biologia Computacional , Simulação por Computador , Microbiota , Modelos Biológicos , Microbiota/fisiologia , Interações Microbianas/fisiologia , Algoritmos , Animais , Microbioma Gastrointestinal/fisiologia
20.
Mech Ageing Dev ; 220: 111956, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38906383

RESUMO

Psychological stress is a major contributing factor to several health problems (e.g., depression, cardiovascular disease). Around 35 % of the world's population suffers from it, including younger generations. Physiologically, stress manifests through neuroendocrine pathways (Hypothalamic-Pituitary-Adrenal (HPA) axis and Sympathetic-Adrenal-Medullary (SAM) system) which culminate in the production of stress mediators like cortisol, epinephrine and norepinephrine. Stress and its mediators have been associated to body aging, through molecular mechanisms such as telomere attrition, mitochondrial dysfunction, cellular senescence, chronic inflammation, and dysbiosis, among others. Regarding its impact in the skin, stress impacts its structural integrity and physiological function. Despite this review focusing on several hallmarks of aging, emphasis was placed on skin microbiota dysbiosis. In this line, several studies, comprising different age groups, demographic contexts and body sites, have reported skin microbiota alterations associated with aging, and some effects of stress mediators on skin microbiota have also been reviewed in this paper. From a different perspective, since it is not a "traditional" stress mediator, oxytocin, a cortisol antagonist, has been related to glucorticoids inhibition and to display positive effects on cellular aging. This hormone dysregulation has been associated to psychological issues such as depression, whereas its upregulation has been linked to positive social interaction.


Assuntos
Envelhecimento , Microbiota , Pele , Estresse Psicológico , Humanos , Pele/microbiologia , Pele/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/microbiologia , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Microbiota/fisiologia , Ocitocina/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Senescência Celular/fisiologia , Disbiose/microbiologia , Disbiose/metabolismo , Animais , Sistema Hipófise-Suprarrenal/metabolismo
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