Uncovering fungal community composition in natural habitat of Ophiocordyceps sinensis using high-throughput sequencing and culture-dependent approaches.

BACKGROUND: The fungal communities inhabiting natural Ophiocordyceps sinensis play critical ecological roles in alpine meadow ecosystem, contribute to infect host insect, influence the occurrence of O. sinensis, and are repertoire of potential novel metabolites discovery. However, a comprehensive understanding of fungal communities of O. sinensis remain elusive. Therefore, the present study aimed to unravel fungal communities of natural O. sinensis using combination of high-throughput sequencing and culture-dependent approaches. RESULTS: A total of 280,519 high-quality sequences, belonging to 5 fungal phyla, 15 classes, 41 orders, 79 families, 112 genera, and 352 putative operational taxonomic units (OTUs) were obtained from natural O. sinensis using high-throughput sequencing. Among of which, 43 genera were identified in external mycelial cortices, Ophiocordyceps, Sebacinia and Archaeorhizomyces were predominant genera with the abundance of 95.86, 1.14, 0.85%, respectively. A total of 66 genera were identified from soil microhabitat, Inocybe, Archaeorhizomyces, unclassified Thelephoraceae, Tomentella, Thelephora, Sebacina, unclassified Ascomycota and unclassified fungi were predominant genera with an average abundance of 53.32, 8.69, 8.12, 8.12, 7.21, 4.6, 3.08 and 3.05%, respectively. The fungal communities in external mycelial cortices were significantly distinct from soil microhabitat. Meanwhile, seven types of culture media were used to isolate culturable fungi at 16 °C, resulted in 77 fungal strains identified by rDNA ITS sequence analysis, belonging to 33 genera, including Ophiocordyceps, Trichoderma, Cytospora, Truncatella, Dactylonectria, Isaria, Cephalosporium, Fusarium, Cosmospora and Paecilomyces, etc.. Among all culturable fungi, Mortierella and Trichoderma were predominant genera. CONCLUSIONS: The significantly differences and overlap in fungal community structure between two approaches highlight that the integration of high-throughput sequencing and culture-dependent approaches would generate more information. Our result reveal a comprehensive understanding of fungal community structure of natural O. sinensis, provide new insight into O. sinensis associated fungi, and support that microbiota of natural O. sinensis is an untapped source for novel bioactive metabolites discovery.

Research progress in bioremediation of petroleum pollution.

With the enhancement of environmental protection awareness, research on the bioremediation of petroleum hydrocarbon environmental pollution has intensified. Bioremediation has received more attention due to its high efficiency, environmentally friendly by-products, and low cost compared with the commonly used physical and chemical restoration methods. In recent years, bacterium engineered by systems biology strategies have achieved biodegrading of many types of petroleum pollutants. Those successful cases show that systems biology has great potential in strengthening petroleum pollutant degradation bacterium and accelerating bioremediation. Systems biology represented by metabolic engineering, enzyme engineering, omics technology, etc., developed rapidly in the twentieth century. Optimizing the metabolic network of petroleum hydrocarbon degrading bacterium could achieve more concise and precise bioremediation by metabolic engineering strategies; biocatalysts with more stable and excellent catalytic activity could accelerate the process of biodegradation by enzyme engineering; omics technology not only could provide more optional components for constructions of engineered bacterium, but also could obtain the structure and composition of the microbial community in polluted environments. Comprehensive microbial community information lays a certain theoretical foundation for the construction of artificial mixed microbial communities for bioremediation of petroleum pollution. This article reviews the application of systems biology in the enforce of petroleum hydrocarbon degradation bacteria and the construction of a hybrid-microbial degradation system. Then the challenges encountered in the process and the application prospects of bioremediation are discussed. Finally, we provide certain guidance for the bioremediation of petroleum hydrocarbon-polluted environment.

Association between B vitamins and schizophrenia: A population-based case-control study.

To explore the association between schizophrenia and six types of B vitamins, including choline, biotin, riboflavin, pyridoxamine, pyridoxine and nicotinamide, based on the hydrophilic interaction liquid chromatography column (HILIC) Liquid Chromatography-Mass Spectrometry (LC-MS) platform. We conducted the case-control study between November 2015 and September 2016 in Weifang, Shandong Province, China. Blood samples from 128 cases of schizophrenia and 101 controls were collected, and B vitamin were measured by LC-MS coupled with HILIC. The HILIC UPLC-MS based analysis of serum B vitamins levels from 128 cases (30 cases with first-episode, 98 cases with relapse) and 101 controls were performed. The results indicated that lower pyridoxine level and schizophrenia was related. (total cases versus controls: ß= -0.215, 95% CI: -0.271, -0.125, p < 0.001; first-episode cases versus controls: ß = -0.190, 95% CI: -0.277, -0.103, p < 0.001). Higher nicotinamide level was also associated with schizophrenia after adjusting confounders (ß = 0.343, 95% CI: 0.022, 0.664, p = 0.036). Other four B vitamins, including biotin, riboflavin, pridoxamine and choline, were showed no statistically difference in cases versus controls, first episode cases versus relapse cases. Two types of B Vitamins, pyridoxine and nicotinamide, show significant association with the schizophrenia.