Project description:To effectively monitor microbial populations in acidic environments and bioleaching systems, a comprehensive 50-mer-based oligonucleotide microarray was developed based on most of the known genes associated with the acidophiles. This array contained 1,072 probes in which there were 571 related to 16S rRNA and 501 related to functional genes. Acid mine drainage (AMD) presents numerous problems to the aquatic life and surrounding ecosystems. However, little is known about the geographic distribution, diversity, composition, structure and function of AMD microbial communities. In this study, we analyzed the geographic distribution of AMD microbial communities from twenty sites using restriction fragment length polymorphism (RFLP) analysis of 16S rRNA genes, and the results showed that AMD microbial communities were geographically distributed and had high variations among different sites. Then an AMD-specific microarray was used to further analyze nine AMD microbial communities, and showed that those nine AMD microbial communities had high variations measured by the number of detected genes, overlapping genes between samples, unique genes, and diversity indices. Statistical analyses indicated that the concentrations of Fe, S, Ca, Mg, Zn, Cu and pH had strong impacts on both phylogenetic and functional diversity, composition, and structure of AMD microbial communities. This study provides insights into our understanding of the geographic distribution, diversity, composition, structure and functional potential of AMD microbial communities and key environmental factors shaping them. This study investigated the geographic distribution of Acid Mine Drainages microbial communities using a 16S rRNA gene-based RFLP method and the diversity, composition and structure of AMD microbial communities phylogenetically and functionally using an AMD-specific microarray which contained 1,072 probes ( 571 related to 16S rRNA and 501 related to functional genes). The functional genes in the microarray were involved in carbon metabolism (158), nitrogen metabolism (72), sulfur metabolism (39), iron metabolism (68), DNA replication and repair (97), metal-resistance (27), membrane-relate gene (16), transposon (13) and IST sequence (11).
Project description:The facultative intracellular bacterium Fusobacterium nucleatum (Fn), mediates tumorigenesis and progression in CRC. However, the origin of intracellular Fn and the role of Fn-infected phagocytes in tumor microenvironment remains unclear. Here, we observed Fn-infected neutrophils/macrophages (PMNs/MΦ) is accumulated in CRC tumor tissues. Fn can survive inside of PMNs by reducing intracellular ROS levels. The lysozyme inhibitor Fn-MliC induced the expression of the CX3CR1 which suppressed apoptosis of phagocytes. Fn-infected phagocytes can transfer Fn to tumor cells, and Fn-infected CRC cells recruited PMNs and MΦ/monocytes through the CXCL2/8-CXCR2 and CCL5/CCR5 axis. Intracellular Fn upregulated PD-L1 expression through activating NF-κB/STAT3 pathway in PMNs. PD-L1+ PMNs infiltration promotes CRC metastasis and weaken the efficacy of immunotherapy, and eradication intracellular Fn infection retarded the Fn promoted tumor progressing in mice. These results suggest that Fn volved efficient strategies to exploit phagocytes to home to tumor tissues, inhibited immune responses and facilitate tumor metastasis.
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:Samples of oil and production water were collected from five wells of the Qinghai Oilfield, China, and subjected to GeoChip hybridization experiments for microbial functional diversity profiling. Unexpectedly, a remarkable microbial diversity in oil samples, which was higher than that in the corresponding water samples, was observed, thus challenging previously believed assumptions about the microbial diversity in this ecosystem. Hierarchical clustering separated oil and water samples, thereby indicating distinct functional structures in the samples. Genes involved in the degradation of hydrocarbons, organic remediation, stress response, and carbon cycling were significantly abundant in crude oil, which is consistent with their important roles in residing in oil. Association analysis with environmental variables suggested that oil components comprising aromatic hydrocarbons, aliphatic hydrocarbons, and a polar fraction with nitrogen-, sulfur-, and oxygen-containing compounds were mainly influential on the structure of the microbial community. Furthermore, a comparison of microbial communities in oil samples indicated that the structures were depth/temperature-dependent. To our knowledge, this is the first thorough study to profile microbial functional diversity in crude oil samples. From the Qinghai Oilfield located in the Tibetan Plateau, northwest China, oil production mixtures were taken from four oil production wells (No. 813, 516, 48 and 27) and one injection well (No. 517) in the Yue-II block. The floating oil and water phases of the production mixtures were separated overnight by gravitational separation. Subsequently, the microbial community and the characteristics of the water solution (W813, W516, W48, and W27) and floating crude oil (O813, O516, O48, and O27) samples were analyzed. A similar analysis was performed with the injection water solution (W517).
Project description:Samples of oil and production water were collected from five wells of the Qinghai Oilfield, China, and subjected to GeoChip hybridization experiments for microbial functional diversity profiling. Unexpectedly, a remarkable microbial diversity in oil samples, which was higher than that in the corresponding water samples, was observed, thus challenging previously believed assumptions about the microbial diversity in this ecosystem. Hierarchical clustering separated oil and water samples, thereby indicating distinct functional structures in the samples. Genes involved in the degradation of hydrocarbons, organic remediation, stress response, and carbon cycling were significantly abundant in crude oil, which is consistent with their important roles in residing in oil. Association analysis with environmental variables suggested that oil components comprising aromatic hydrocarbons, aliphatic hydrocarbons, and a polar fraction with nitrogen-, sulfur-, and oxygen-containing compounds were mainly influential on the structure of the microbial community. Furthermore, a comparison of microbial communities in oil samples indicated that the structures were depth/temperature-dependent. To our knowledge, this is the first thorough study to profile microbial functional diversity in crude oil samples.
Project description:A comparision of soil microbial functional genes of three types of subtropical broad-leaved forests Microbial functional structure was significantly different among SBFs (P < 0.05). Compared to the DBF and the EBF, the MBF had higher alpha-diversity of functional genes but lower beta-diversity, and showed more complex functional gene networks.
Project description:To effectively monitor microbial populations in acidic environments and bioleaching systems, a comprehensive 50-mer-based oligonucleotide microarray was developed based on most of the known genes associated with the acidophiles. This array contained 1,072 probes in which there were 571 related to 16S rRNA and 501 related to functional genes. Acid mine drainage (AMD) presents numerous problems to the aquatic life and surrounding ecosystems. However, little is known about the geographic distribution, diversity, composition, structure and function of AMD microbial communities. In this study, we analyzed the geographic distribution of AMD microbial communities from twenty sites using restriction fragment length polymorphism (RFLP) analysis of 16S rRNA genes, and the results showed that AMD microbial communities were geographically distributed and had high variations among different sites. Then an AMD-specific microarray was used to further analyze nine AMD microbial communities, and showed that those nine AMD microbial communities had high variations measured by the number of detected genes, overlapping genes between samples, unique genes, and diversity indices. Statistical analyses indicated that the concentrations of Fe, S, Ca, Mg, Zn, Cu and pH had strong impacts on both phylogenetic and functional diversity, composition, and structure of AMD microbial communities. This study provides insights into our understanding of the geographic distribution, diversity, composition, structure and functional potential of AMD microbial communities and key environmental factors shaping them.
Project description:Fusobacterium nucleatum (Fn) infection has been linked to the initiation and development of colorectal cancer (CRC). However, the underlying mechanisms remains unexplored. Tissues from Fn-infected mice were first collected for single-cell RNA sequencing. we investigated the correlation between Fn infection and accumulations of tumor associated macrophages (TAMs) in tissues from human CRC or AOM/DSS treated mice. The impact of Fn on biological function of TAMs were interrogated. We deciphered the mechanisms for interaction between Fn and TAMs in CRC. We explored the impact of Fn infection on immune-checkpoint blockade (ICB) treatment in a multicohort study.The analysis of single-cell RNA sequencing revealed an enrichment of TAMs in Fn positive tissues. A significant correlation between Fn DNA level and TAMs was observed. Functionally, Fn could recruit TAMs in CRC tissues and promote their biological functions by enhancing PD-L1 expression and thus suppressing CD8+ T cells. Mechanistically, Fn infection led to increased secreted IL-6 via TLR4/MyD88/NF-κB pathways, and the activated IL-6/STAT3 pathway enhanced PD-L1 expression in TAMs. By using several mice models, we found IL-6 inhibition, loss of MyD88 or anti-PD-L1 treatment could significantly inhibit tumorigenesis. Clinically, Fn positive patients tended to be more sensitive to ICB treatment, with a better prognosis than Fn-negative patients.
Project description:Fusobacterium nucleatum (Fn) infection has been linked to the initiation and development of colorectal cancer (CRC). However, the underlying mechanisms remains unexplored. Tissues from Fn-infected mice were first collected for single-cell RNA sequencing. we investigated the correlation between Fn infection and accumulations of tumor associated macrophages (TAMs) in tissues from human CRC or AOM/DSS treated mice. The impact of Fn on biological function of TAMs were interrogated. We deciphered the mechanisms for interaction between Fn and TAMs in CRC. We explored the impact of Fn infection on immune-checkpoint blockade (ICB) treatment in a multicohort study.The analysis of single-cell RNA sequencing revealed an enrichment of TAMs in Fn positive tissues. A significant correlation between Fn DNA level and TAMs was observed. Functionally, Fn could recruit TAMs in CRC tissues and promote their biological functions by enhancing PD-L1 expression and thus suppressing CD8+ T cells. Mechanistically, Fn infection led to increased secreted IL-6 via TLR4/MyD88/NF-κB pathways, and the activated IL-6/STAT3 pathway enhanced PD-L1 expression in TAMs. By using several mice models, we found IL-6 inhibition, loss of MyD88 or anti-PD-L1 treatment could significantly inhibit tumorigenesis. Clinically, Fn positive patients tended to be more sensitive to ICB treatment, with a better prognosis than Fn-negative patients.