In recent years, as an emerging material, nanomaterials have rapidly expanded from laboratories to large-scale industrial productions. Along with people’s productive activities, these nanomaterials can enter the natural environment of soil, water and atmosphere through various ways. At present, a large number of reports have proved that nanomaterials have certain toxic effects on bacteria, algae, plants, invertebrates, mammalian cell lines and mammals in these environments, but people still know little about the ecotoxicology of nanomaterials. Most relevant studies focus on the responses of model strains to nanomaterials in pure culture conditions, but these results do not fully represent the response of microbial communities to nanomaterials in natural environments. Over the years, the effect of nanomaterials infiltrated into the natural environment on the microbial communities has become a popular topic in the field of nano-ecological environment research. It was found that under different environmental conditions, nanomaterials have various effects on the microbial communities. The medium; the coexisting pollutants in the environment and the structure, particle size and surface modification of nanomaterials may cause changes in the structure and function of microbial communities. This paper systematically summarizes the impacts of different nanomaterials on microbial communities in various environments, which can provide a reference for us to evaluate the impacts of nanomaterials released into the environment on the microecology and has certain guiding significance for strengthening the emission control of nanomaterials pollutants.

Salinity acts as a critical environmental filter on microbial communities in natural systems, negatively affecting microbial diversity. However, how salinity affects microbial community assembly remains unclear. This study used Wendeng multi-pond saltern as a model to evaluate the prokaryotic community composition and diversity and quantify the relative importance of ecological processes across salinity gradients. The results showed that low-saline salterns (45–80 g/L) exhibited higher bacterial diversity than high-saline salterns (175–265 g/L). The relative abundance of taxa assigned to Halomicrobiaceae, Rhodobacteraceae, Saprospiraceae, and Thiotrichaceae exhibited a hump-shaped dependence on increasing salinity. Salinity and pH were the primary environmental factors that directly or indirectly determined the composition and diversity of prokaryotic communities. Microbial co-occurrence network dynamics were more complex in the sediment than in the water of salterns. An infer Community Assembly Mechanisms by Phylogenetic-bin-based null model analysis (iCAMP) showed that microbial community assembly in sediment and water differed. Our findings provide more information about microbial community structure and the importance of various ecological processes in controlling microbial community diversity and succession along salinity gradients in water and sediment.

A novel Gram-stain-negative, facultatively anaerobic, yellowish and agar-digesting marine bacterium, designated strain QM50T, was isolated from coastal seawater in an aquaculture site near Qingdao, China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate represented a member of the genus Colwellia and exhibited the highest sequence similarity (97.4 %) to Colwellia aestuarii SMK-10T. Average nucleotide identity (ANI) values based on draft genome sequences between strain QM50T and C. aestuarii KCTC 12480T showed a relatedness of 72.0 % (ANIb) and 85.1 % (ANIm). Cells of strain QM50T were approximately 0.3–0.6×0.8–2.5 µm in size and motile by means of a polar flagellum. Growth occurred in the presence of 1.0–6.0 % (w/v) NaCl (optimum, 2.0–3.0 %), at pH 6.5–8.5 (optimum, pH 7.0) and at 4–37 °C (optimum, 28–30 °C). Strain QM50T was found to contain ubiquinone 8 (Q-8) as the predominant ubiquinone and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), C16 : 0 and C17 : 1ω8c as the main cellular fatty acids. Phosphatidylethanolamine and phosphatidylglycerol were found to be major polar lipids. The DNA G+C content of strain QM50T was determined to be 35.7 mol%. On the basis of phylogenetic and phenotypic data, strain QM50T represents a novel species of the genus Colwellia , for which the name Colwellia agarivorans sp. nov. is proposed. The type strain is QM50T (=KCTC 52273T=MCCC 1H00143T).

Our model offers insight into the ecological properties of SRB and identifies a previously undocumented dimension of OM degradation. This targeted inhibition approach could provide a novel framework for illustrating how functional microbial taxa associate the composition and structure of the microbial community, molecular ecological network, and community assembly processes.

A Gram-stain-positive, facultatively anaerobic bacterium, strain JDX10^T, was isolated from a soil sample of Fildes Peninsula, Antarctica. Cells of the strain were irregular rod-shaped and non-motile. Cells grew at 4–40 °C (optimum, 28 °C), at pH 6.0–9.0 (optimum, 7.5) and with 0.0–3.0 % (w/v) NaCl (optimum, 1.0 %). According to phylogenetic analysis based on 16S rRNA gene sequences, strain JDX10^T was associated with the genus Tessaracoccus , and showed highest similarities to Tessaracoccus rhinocerotis CCTCC AB 2013217^T (97.2 %), Tessaracoccus flavescens SST-39^T (96.9 %) and Tessaracoccus terricola JCM 32157^T (96.9 %). The average nucleotide identity scores of strain JDX10^T to T. rhinocerotis CCTCC AB 2013217^T and T. bendigoensis JCM 13525^T were 74.8 and 73.3 %, respectively and the Genome-to-Genome Distance Calculator scores were 19.2 and 18.7 %, respectively. The major (>10.0 %) cellular fatty acid was anteiso-C_15 : 0. The predominant isoprenoid quinone was MK-10(H₄). The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and one unidentified glycolipid. The phylogenetic analysis and physiological and biochemical data showed that strain JDX10^T should be classified as representing a novel species in the genus Tessaracoccus , for which the name Tessaracoccus antarcticus sp. nov. is proposed. The type strain is JDX10^T (=MCCC 1H00351^T=KCTC 49242^T).