Functional Guilds, Community Assembly, and Co-occurrence Patterns of Fungi in Metalliferous Mine Tailings Ponds in Mainland China.

Metalliferous mine tailings ponds are generally characterized by low levels of nutrient elements, sustained acidic conditions, and high contents of toxic metals. They represent one kind of extreme environments that are believed to resemble the Earth's early environmental conditions. There is increasing evidence that the diversity of fungi inhabiting mine tailings ponds is much higher than previously thought. However, little is known about functional guilds, community assembly, and co-occurrence patterns of fungi in such habitats. As a first attempt to address this critical knowledge gap, we employed high-throughput sequencing to characterize fungal communities in 33 mine tailings ponds distributed across 18 provinces of mainland China. A total of 5842 fungal phylotypes were identified, with saprotrophic fungi being the major functional guild. The predictors of fungal diversity in whole community and sub-communities differed considerably. Community assembly of the whole fungal community and individual functional guilds were primarily governed by stochastic processes. Total soil nitrogen and total phosphorus mediated the balance between stochastic and deterministic processes of the fungal community assembly. Co-occurrence network analysis uncovered a high modularity of the whole fungal community. The observed main modules largely consisted of saprotrophic fungi as well as various phylotypes that could not be assigned to known functional guilds. The richness of core fungal phylotypes, occupying vital positions in co-occurrence network, was positively correlated with edaphic properties such as soil enzyme activity. This indicates the important roles of core fungal phylotypes in soil organic matter decomposition and nutrient cycling. These findings improve our understanding of fungal ecology of extreme environments.

Hidden diversity and potential ecological function of phosphorus acquisition genes in widespread terrestrial bacteriophages.

Phosphorus (P) limitation of ecosystem processes is widespread in terrestrial habitats. While a few auxiliary metabolic genes (AMGs) in bacteriophages from aquatic habitats are reported to have the potential to enhance P-acquisition ability of their hosts, little is known about the diversity and potential ecological function of P-acquisition genes encoded by terrestrial bacteriophages. Here, we analyze 333 soil metagenomes from five terrestrial habitat types across China and identify 75 viral operational taxonomic units (vOTUs) that encode 105 P-acquisition AMGs. These AMGs span 17 distinct functional genes involved in four primary processes of microbial P-acquisition. Among them, over 60% (11/17) have not been reported previously. We experimentally verify in-vitro enzymatic activities of two pyrophosphatases and one alkaline phosphatase encoded by P-acquisition vOTUs. Thirty-six percent of the 75 P-acquisition vOTUs are detectable in a published global topsoil metagenome dataset. Further analyses reveal that, under certain circumstances, the identified P-acquisition AMGs have a greater influence on soil P availability and are more dominant in soil metatranscriptomes than their corresponding bacterial genes. Overall, our results reinforce the necessity of incorporating viral contributions into biogeochemical P cycling.

Sporoderm-broken spore powder of Ganoderma lucidum ameliorate obesity and inflammation process in high-fat diet-induced obese mice.

Objective: This study examined the anti-obesity and anti-inflammatory effects of sporoderm-broken spore powder of Ganoderma lucidum (SSPL) against obese mice fed with a high-fat diet. Methods: Four groups of C57BL/6J mice were randomly assigned to the following diets: control diet (CD); high-fat diet (HD); high-fat diet plus l-carnitine (HDL); and high-fat diet with sporoderm-broken spore powder of Ganoderma lucidum (HDG). They were subjected to 12 weeks of testing. Results: Supplementation with SSPL lowered weight gain caused by a high-fat diet and improved serum and liver lipid levels, and histological investigation indicated that the HDG group had a significant reduction in liver lipid deposits and adipocyte size in epididymal fat. SSPL administration decreased the expression of genes associated with inflammation and fat anabolism, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-1ß (IL-1ß), peroxisome proliferator-activated receptorγ (PPARγ), sterol regulatory element-binding protein 1c (SREBP-1c), fatty acid synthase (FAS), acetyl-coenzyme A (CoA) carboxylase (ACC), and leptin. SSPL therapy raised the levels of PPARα, carnitine palmitoyl-transferase 1 (CPT-1), acyl-CoA oxidase1 (ACOX1), and adiponectin. Conclusion: In summary, SSPL protected mice against developing obesity caused by increased fat intake by regulating inflammatory factors and lipid metabolism. Our findings indicate that SSPL is a potentially beneficial healthy meal for treating obesity.

[Expression and clinical significance of COX-2, p-Stat3, and p-Stat5 in esophageal carcinoma].

BACKGROUND & OBJECTIVE: Cyclooxygenase-2 (COX-2) and signal transducers and activators of transcription (STAT) are closely correlated to the genesis of tumors. This study was to investigate the expression and clinical significance of COX-2, p-Stat3 and p-Stat5 (the activated forms of Stat3 and Stat5) in various lesions of esophageal tissues, and to analyze their correlations to clinicopathologic features of esophageal squamous cell carcinoma (ESCC). METHODS: The expression of COX-2, p-Stat3, and p-Stat5 in 59 specimens of ESCC, 24 specimens of squamous dysplasia, and 18 specimens of normal squamous epithelium was examined by SP immunohistochemistry. Their correlations to clinicopathologic features of ESCC were analyzed. RESULTS: The protein level of COX-2 was significantly higher in ESCC and squamous dysplasia than in normal squamous epithelium (2.10+/-1.77 and 1.85+/-1.24 vs. 0.83+/-0.46, P<0.05). The protein level of p-Stat3 was 0 in normal squamous epithelium, 0.76+/-0.59 in squamous dysplasia, and 2.83+/-1.27 in ESCC. The protein level of p-Stat5 was 1.98+/-0.78 in normal squamous epithelium, 3.92+/-0.41 in squamous dysplasia, and 5.02+/-0.34 in ESCC. There were significant differences among the 3 groups (P<0.05). In ESCC, COX-2 expression was correlated to lymph node metastasis and differentiation (P<0.05); p-Stat3 expression was correlated to tumor invasion depth (P<0.05); but p-Stat5 expression had no correlation to clinicopathologic features. COX-2 expression was positively correlated to both p-Stat3 expression and p-Stat5 expression in ESCC. CONCLUSIONS: The up-regulation of COX-2, p-Stat3, and p-Stat5 may be correlated to the carcinogenesis of ESCC. The activation of Stat3 is correlated to the aggressive behavior of ESCC.