Similarity of Chinese and Pakistani oral microbiome.

Oral microbiota is vital for human health and can be affected by various factors (i.e. diets, ethnicity). However, few studies have compared oral microbiota of individuals from different nationalities in the same environment. Here, we explored the assembly and interaction of oral microbial communities of Chinese and Pakistanis in one university. Firmicutes and Proteobacteria were the predominant microorganisms in the oral cavity of Chinese and Pakistanis. Streptococcus and Neisseria were the dominant genera of China, while Streptococcus and Haemophilus were the dominant genera of Pakistanis. In addition, the oral community membership and structure were not influenced by season, Chinese/Pakistani student and gender, reflecting the stability of the human oral microbiome. The beta diversity of oral microbiomes between Chinese and Pakistanis significantly differed in winter, but not in spring. The alpha diversity of Chinese students and Pakistani students was similar. Moreover, oral microbial community of both Chinese and Pakistani students was mainly driven by stochastic processes. The microbial network of Chinese was more complexity and stability than that of Pakistanis. Our study uncovers the characteristics of human oral microbiota, which is of great significance for oral and human health.

Copper and temperature shaped abundant and rare community assembly respectively in the Yellow River.

Untangling assembly and microbial interaction of abundant and rare microbiota in aquatic ecosystem is pivotal for understanding how community assembly respond to environmental variables and co-occurrence patterns. Here, we explored the assembly mechanisms, their drivers, and species co-occurrence of abundant and rare microbiomes in the Yellow River using 16S rRNA gene sequencing in Lanzhou, China. Here, abundant community was ubiquitous across all sites, whereas rare community was uneven distributed. The richness and community dissimilarity of rare taxa were significantly greater than those of abundant ones. Stochastic processes structured the rare community assembly in spring and winter, while deterministic processes shaped the abundant and rare community assembly in other seasons and all sites. Copper and water temperature mediated the balance between deterministic and stochastic processes of abundant and rare community, respectively. A few abundant taxa with closer relationships frequently occupied central positions and had a great effect on other co-occurrences in the network, while the majority of keystone microbiota were rare microbiome and played a considerable part in maintaining the network structure. Our study provides some ecological proposals for water quality management and ecological stability of the Yellow River. KEY POINTS: • Deterministic process dominated abundant and rare community assembly. • Cu and TW mediated the balance of abundant and rare community assembly respectively. • Abundant taxa had a greater effect on other co-occurrences in the network.

Insight into the dynamics of drinking water resistome in China.

Antibiotic resistance (AR) is a serious environmental hazard of the current age. Antibiotic resistance genes (ARGs) are the fundamental entities that spread AR in the environment. ARGs are likely to be transferred from the non-pathogenic to pathogenic microbes that might ultimately be responsible for the AR in humans and other organisms. Drinking water (DW) is the primary interaction route between ARGs and humans. Being the highest producer and consumer of antibiotics China poses a potential threat to developing superbugs and ARGs dissemination. Herein, we comprehensively seek to review the ARGs from dominant DW sources in China. Furthermore, the origin and influencing factors of the ARGs to the DW in China have been evaluated. Commonly used methods, both classical and modern, are being compiled. In addition, the risk posed and mitigation strategies of DW ARGs in China have been outlined. Overall, we believe this review would contribute to the assessment of ARGs in DW of China and their dissemination to humans and other animals and ultimately help the policymakers and scientists in the field to counteract this problem on an emergency basis.

Deterministic Processes Shape Abundant and Rare Bacterial Communities in Drinking Water.

The deep mechanisms shaping bacterial assembly are a crucial challenge in drinking water ecosystem. However, much less is known about seasonal diversity distributions and assembly mechanisms of abundant and rare bacteria in drinking water. The combination of environmental variables and high-throughput 16S rRNA gene sequencing was conducted to examine the composition, assembly, co-occurrence patterns of abundant and rare bacteria from five drinking water sites across four seasons in one year in China. The results indicated that abundant taxa were mainly composed of Rhizobiales_UG1, Sphingomonadales_UG1, and Comamonadaceae, while rare taxa were Sphingomonadales_UG1, Rhizobiales_UG2, and Rhizobiales_UG1. The richness of rare bacteria was greater than that of abundant ones, and the richness had no differences among seasons. The beta diversity was significantly discrepant in abundant and rare communities and among seasons. Deterministic mechanism accounted for a larger contribution to abundant taxa than rare taxa. Furthermore, water temperature had higher effects on abundant microbiome than rare ones. Co-occurrence network analysis indicated that abundant taxa that occupied frequently in central positions had stronger effect on co-occurrence network. In our study, these results collectively suggested that rare bacteria respond to environmental variables with an analogical pattern to abundant counterparts (similar community assembly), but their ecological diversities, driving forces, and co-occurrence patterns were not equivalent in drinking water.

The source, fate and prospect of antibiotic resistance genes in soil: A review.

Antibiotic resistance genes (ARGs), environmental pollutants of emerging concern, have posed a potential threat to the public health. Soil is one of the huge reservoirs and propagation hotspot of ARGs. To alleviate the potential risk of ARGs, it is necessary to figure out the source and fate of ARGs in the soil. This paper mainly reviewed recent studies on the association of ARGs with the microbiome and the transmission mechanism of ARGs in soil. The compositions and abundance of ARGs can be changed by modulating microbiome, soil physicochemical properties, such as pH and moisture. The relationships of ARGs with antibiotics, heavy metals, polycyclic aromatic hydrocarbons and pesticides were discussed in this review. Among the various factors mentioned above, microbial community structure, mobile genetic elements, pH and heavy metals have a relatively more important impact on ARGs profiles. Moreover, human health could be impacted by soil ARGs through plants and animals. Understanding the dynamic changes of ARGs with influencing factors promotes us to develop strategies for mitigating the occurrence and dissemination of ARGs to reduce health risks.

[Spatial-temporal evolution of ecological land and influence factors in Wuhan urban agglome-ration based on geographically weighted regression model]. / åŸºäºŽåœ°ç†åŠ æƒå›žå½’æ¨¡åž‹çš„æ­¦æ±‰åŸŽå¸‚åœˆç”Ÿæ€ç”¨åœ°æ—¶ç©ºæ¼”å˜åŠå½±å“å› ç´ .

Ecological land is essential to sustainable development of urban agglomeration. Based on the results of remote sensing image interpretation, we analyzed the spatial-temporal evolution of ecological land in 32 research units of ecological land in Wuhan urban agglomeration in 2000-2005, 2005-2010 and 2010-2015, using the land use transition matrix, exploratory regression analysis, the ordinary least squares (OLS) model, and geographically weighted regression (GWR) model. Then, the best regression model was selected after perfecting the traditional index system of influencing factors by data of the location and quantitative information of companies, enterprises and life services, etc., and conducting exploratory regression analysis. Finally, we analyzed the influencing factors and spatial differentiation rules of different research periods with GWR model. The results showed that, from 2000 to 2015, the amount of transition from ecological land use to non-ecological land use in the urban agglomeration showed an inverted U-shaped change pattern, and the space showing the expanding trend from point to surface. Land use patterns of 8.4% area had changed in the urban agglomeration, among which the conversion of cultivated land, forest land, grassland, water body and unused land to non-ecological land accounted for 41.9% of the total area. The spatial pattern gradually expanded from the central urban area of Wuhan to the periphery of the municipal sub-center and county-level towns. The total number of passing models in the three stages of exploratory regression analysis was 326. The GWR and OLS regression were used for comparative analysis of all models. The adjusted R2 in the three stages of selected models were 0.83, 0.91 and 0.76, respectively. The former improved by 0.02, 0.03 and 0.02, and the AICc decreased by 2.88, 3.42 and 0.83, respectively. The results of GWR model showed substantially spatial differentiation of influencing factors of ecological land evolution in Wuhan urban agglomeration, and that the influence patterns was dominated by gradual transition in different directions in space, with other patterns such as "V" distribution. The effects of spatial factors were significant. The potential information of spatial data enhanced the interpretation of ecological land evolution within the urban agglomeration.