Project description:Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River.
Project description:Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River. Three groups of samples, A, B and C. Every group has 3 replicates.
Project description:Seagrass meadows are highly productive ecosystems that are considered hotspots for carbon sequestration. The decline of seagrass meadows of various species has been documented worldwide, including that of Cymodocea nodosa, a widespread seagrass in the Mediterranean Sea. To assess the influence of seagrass decline on the metabolic profile of sediment microbial communities, metaproteomes from two sites, one without vegetation and one with a declining Cymodocea nodosa meadow, were characterised at monthly intervals from July 2017 to October 2018. The differences in the metabolic profile observed between the vegetated and nonvegetated sediment before the decline were more pronounced in the deeper parts of the sediment and disappeared with the decay of the roots and rhizomes. During the decline, the protein richness and diversity of the metabolic profile of the microbial communities inhabiting the nonvegetated sediment became similar to those observed for the vegetated communities. Temporal shifts in the structure of the metabolic profile were only observed in the nonvegetated sediment and were also more pronounced in the deeper parts of the sediment. The assessment of the dynamics of proteins involved in the degradation of organic matter, such as ABC transporters, fermentation-mediating enzymes, and proteins involved in dissimilatory sulphate reduction, reflected the general dynamics of the metabolic profile. Overall, the metabolic profile of the microbial communities inhabiting the nonvegetated sediment was influenced by the decline of seagrass, with stronger shifts observed in the deeper parts of the sediment.
Project description:We established simple synthetic microbial communities in a microcosm model system to determine the mechanisms that underlay cross-feeding in microbial methane-consuming communities. Co-occurring strains from Lake Washington sediment were used that are involved in methane consumption, a methanotroph and two non-methanotrophic methylotrophs.
Project description:Numerous studies signify that diets rich in phytochemicals reduce the risk of inflammatory bowel diseases (IBDs). However, their effects are often not uniform among individuals, possibly due to inter-individual variation in gut microbiota. The host indigenous gut microbiota and their metabolites have emerged as factors that greatly influence the efficacy of dietary interventions. The biological activities, mechanisms of actions and the specific targets of several microbial metabolites are unknown. Urolithin A (UroA) is one such natural microbial metabolite, which showed (including our recent study) anti-carcinogenic, anti-oxidative and anti-inflammatory activities. The goal of the experiment to determine if Urolithin A blocks the genes induced by lipopolysaccharide (mimicking bacterial effects on colon) as well as determine effects of Urolithin A alone.
Project description:Neural circuits driving mammalian behaviors are highly plastic and modulated by internal and external factors, including the gut microbiome. We identify imidazole propionate (ImP), a microbial metabolite linked to metabolic disorders, as a key modulator of brain activity and behavior. Bacterially derived ImP enters the systemic circulation and brain, where it alters neuronal gene expression and activity in the hypothalamus without inducing overt neuroinflammation. Elevating systemic ImP promotes stress-related pathways and disrupts GABAergic/glutamatergic signaling in the hypothalamus before peripheral glucose dysregulation occurs. Similarly, colonization with the ImP-producing bacterium Eggerthella lenta elevates behavioral and molecular features of stress. In a mouse model of type 2 diabetes, the gut microbiome exhibits an enhanced ability to produce ImP, leading to elevated systemic levels that are associated with heightened stress responses. In humans, higher ImP associates with reduced hypothalamic reactivity to food cues, impaired stress-coping, and increased emotional eating, mirroring the causal links between ImP, hypothalamic activity, and stress-related behaviors in mice. Overall, these findings establish ImP as a notable microbial metabolite that links gut dysbiosis to altered hypothalamic function and stress in metabolic disease.
Project description:The increased urban pressures are often associated with specialization of microbial communities. Microbial communities being a critical player in the geochemical processes, makes it important to identify key environmental parameters that influence the community structure and its function.In this proect we study the influence of land use type and environmental parameters on the structure and function of microbial communities. The present study was conducted in an urban catchment, where the metal and pollutants levels are under allowable limits. The overall goal of this study is to understand the role of engineered physicochemical environment on the structure and function of microbial communities in urban storm-water canals. Microbial community structure was determined using PhyoChio (G3) Water and sediment samples were collected after a rain event from Sungei Ulu Pandan watershed of >25km2, which has two major land use types: Residential and industrial. Samples were analyzed for physicochemical variables and microbial community structure and composition. Microbial community structure was determined using PhyoChio (G3)
Project description:Gut microbiota are recognized to be important for anticancer therapy, yet the underlying mechanism is not clear. Herein, we demonstrate that gut microbial metabolite butyrate improves anticancer therapy efficacy by regulating intracellular calcium homeostasis. Butyrate metabolism is activated in hepatocellular carcinoma (HCC) patients. Butyrate supplementation or depletion of short-chain Acyl-CoA dehydrogenase (ACADS), a key enzyme for butyrate metabolism, significantly inhibit HCC proliferation and metastasis. Profiling analysis of genes upregulated by butyrate supplementation or ACADS knockdown reveal that calcium signaling pathway is activated, leading to dysregulation of intracellular calcium homeostasis and production of reactive oxygen species (ROS). Butyrate supplementation improves the therapy efficacy of a tyrosine kinase inhibitor sorafenib. Butyrate and sorafenib co-encapsulated monomethoxy (polyethylene glycol)-poly (D, L-lactide-co-glycolide)-poly(L-lysine)-glypican 3 (PEAL-GPC3) nanoparticles significantly reduce HCC progression. Our findings provide new insight into the mechanisms that the gut microbial metabolites inhibit HCC progression and suggest a translatable therapeutics approach to enhance the clinical targeted therapeutic efficacy.
Project description:The increased urban pressures are often associated with specialization of microbial communities. Microbial communities being a critical player in the geochemical processes, makes it important to identify key environmental parameters that influence the community structure and its function.In this proect we study the influence of land use type and environmental parameters on the structure and function of microbial communities. The present study was conducted in an urban catchment, where the metal and pollutants levels are under allowable limits. The overall goal of this study is to understand the role of engineered physicochemical environment on the structure and function of microbial communities in urban storm-water canals. Water and sediment samples were collected after a rain event from Sungei Ulu Pandan watershed of >25km2, which has two major land use types: Residential and industrial. Samples were analyzed for physicochemical variables and microbial community structure and composition. Functional gene abundance was determined using GeoChip.