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Lekima was a devastating super typhoon hitting China in 2019. Here, we use a high-resolution wave–current coupling model to investigate the impacts of wave–current interaction during Lekima on wave height, storm surge, ocean currents, and momentum balance. The model results were in good agreement with observations. It was found that, in the open waters, the strong currents generated by the typhoon winds reduced the typhoon-induced maximum significant wave heights (MSWHs) by 6%–15%. The baroclinicity of seawater also slightly reduced the MSWHs by approximately 3%. In the coastal waters, the MSWHs were increased by 6%–15% when feedbacks from water levels were considered. The typhoon-induced highest storm surge occurred in the coastal waters right of the typhoon’s landing position. The nonconservative wave forces contributed by approximately 0.1–0.4 m to the most severe storm surge (3 m), with this effect being most prominent in coastal waters. The baroclinicity of seawater generally increased the storm surge but had little influence on very shallow waters. Tides tend to exacerbate storm surge in most nearshore waters, except in a small bay. Waves generally increased the velocity of offshore ocean currents via the wave-breaking-induced acceleration. A cross-shore momentum balance analysis shows that when the typhoon was near the shore, the dominant terms in the momentum equation were the horizontal pressure gradient force and the surface wind stress, and the contribution of wave breaking had similar pattern to that of the wind stress but a lower magnitude. Our findings have significant implications for the numerical modeling of typhoons and the prediction of their impacts in the coastal environment.

Household fuel substitution has been a crucial step for controlling air pollution in China, but the performance evaluation of household fuel substitution policies is overlooked. This study capitalized on the opportunity to use data collected during the household coal-replacement program in North China to evaluate the effect of a mandatory policy on fuel substitution at the micro-level. The results indicate that there is a significant effect of the coal-replacement program on fuel substitution, as we expected. The coal-to-electricity policy is effective in achieving the goal of a clean winter but not a warm winter due to the decline of delivered energy, while the high-quality coal replacement policy results in better performance in delivered energy but no improvement in indoor air quality. It is recommended to prioritize supporting measures on both the supply and demand sides before implementation, along with undertaking differential measures during the implementation phase to better address energy inequality.

The exercise of quantifying the energy consumption data assembled through household surveys, either by the recall-based approach or the meter-based approach, remains a challenging task, especially in rural areas of developing countries. In this article, we propose a device-based bottom-up accounting method for estimating household energy consumption. This method provides microlevel disaggregated estimates at the intensive margin and documents other difficult-to-measure energy consumption such as biomass at the extensive margin. Even though measurement errors of the household survey might still exist, the structured questionnaire of daily routine behavior questions should greatly alleviate the problem. The new method supplements the existing household energy statistical system, improves its flexibility, and is particularly applicable in developing countries and/or rural areas. We apply the method to a Chinese rural household survey and discuss its differences and similarities with the conventional methods.

Invertebrates do not possess adaptive immunity but have evolved a variety of unique repertoires of innate immune sensors. In this study, we explored the immune diversity and specificity of invertebrates based on the lophotrochozoan RLRs, a major component in antiviral immune recognition. By annotating RLRs in the genomes of 58 representative species across metazoan evolution, we explored the gene expansion of RLRs in Lophotrochozoa. Of note, the N-terminal domains of lophotrochozoan RLRs showed the most striking diversity which evolved independently by domain grafting. Exon–intron structures were revealed to be prevalent in the domain grafting of lophotrochozoan RLRs based on an analysis of sibling paralogs and orthologs. In more than half of the cases, the mechanism of ‘exonization/pseudoexonization’ led to the generation of non-canonical N-terminal domains. Transcriptomic studies revealed that many non-canonical RLRs display immune-related expression patterns. Two of these RLRs showed obvious evidence of positive selection, which may be the result of host defense selection pressure. Overall, our study suggests that the complex and unique domain arrangement of lophotrochozoan RLRs might result from domain grafting, exon–intron divergence, expression diversification, and positive selection, which may have led to functionally distinct lophotrochozoan RLRs.

Invertebrates do not possess adaptive immunity but have evolved a variety of unique repertoires of innate immune sensors. In this study, we explored the immune diversity and specificity of invertebrates based on the lophotrochozoan

Marine bacterial strain Bacillus sp. CS30 exhibited high anticancer activity against Huh7.5 human liver cancer. We purified the corresponding anticancer agent by sequential acidic precipitation, methanol extraction, Sephadex LH-20 chromatography, and reversed phase high-performance liquid chromatography (RP-HPLC), then analyzed it in mass spectrometry. Based on the results of purification and mass spectrometry, we deduced that the anticancer agent was the same component as our previously purified antifungal agent surfactin CS30-2. However, to the best of our knowledge, this is the first report on the surfactin possessing both antifungal and anticancer activities. Surfactin CS30-2 was demonstrated to exhibit high anticancer activity in a dose-dependent manner against Huh7.5 liver cancer cells. Further investigation showed that surfactin CS30-2 induced the increased generation of reactive oxygen species (ROS) and severe disruption of cell membrane, thus leading to cell death. However, unlike previously reported surfactins, surfactin CS30-2 caused cancer cell death via necrosis instead of apoptosis.

We conduct a theoretical, first-principles study of thallium sulfide with the space group FM-3M. We determine the electronic structure, phonon dispersion relations, Eliashberg spectral function, electron-phonon coupling constant (λ) and any superconductivity. The results indicate that this structure is characterized by a much larger electronic density of states at the Fermi level. Both the norm-conserving pseudopotential and ultra-soft pseudopotential are used to study its superconducting properties. The transition temperatures (Tc) for superconductivity are 9.3 K and 4.2 K, while the electron–phonon coupling constants are 0.79 and 0.59, respectively. Tc does not increase with increasing pressure. The superconductivity disappears when the pressure reaches 80 GPa.

Household energy consumption in rural areas is strongly related to living standards, poverty alleviation, air pollution and health, but lacks solid analysis due to limited data. This paper first presents a systematical overview of rural household energy consumption in China from 1985 to 2013. To quantify and illustrate the pattern of rural household energy consumption, we use a comprehensive household survey, the Chinese Residential Energy Consumption Survey (CRECS, 2013) to illustrate the energy consumption by seven types of energy and five types of end-use demand. Moreover, we compare the rural household energy consumption in terms of quantity, fuel mix and demand structure by North-South regions, East-Middle-West areas and various countries. We identify the biomass still dominate Chinese rural household energy supply while cooking and space heating are the most energy-intensive demand. The overall energy efficiency for a rural household is 33%, mainly attributed to the massive use of biomass. Policy implications are summarized and discussed.

In the present study, a deep-sea bacterial strain designated Bacillus sp. strain wsm-1 was screened and found to exhibit strong antifungal activity against many plant-pathogenic fungi, and corresponding antifungal agents were thereby purified and determined by tandem mass spectrometry to be two cyclic lipopeptide homologs. These homologs, which were different from any previously reported lipopeptides, were identified to possess identical amino acid sequences of β-amino fatty acid-Asn-Ser-Asn-Pro-Tyr-Asn-Gln and deduced as two novel lipopeptides designated C14 iturin W and C15 iturin W. Electron microscopy observation indicated that both iturin W homologs caused obvious morphological changes and serious disruption of plasma membrane toward fungal cells, while C15 iturin W exhibited more serious cell damages than C14 iturin W did, which was well consistent with the results of the antifungal activity assays. To improve the yield and antifungal activity of iturin W, the effects of different carbon and nitrogen sources and amino acids on production of C14 iturin W and C15 iturin W were investigated. The results indicated that supplements of most of the detected carbon and nitrogen sources could increase the yield of C14 iturin W, but inhibit the yield of C15 iturin W, while supplements of tryptone and most of the detected amino acids could increase the yield of both C14 iturin W and C15 iturin W.IMPORTANCE Plant disease caused by pathogenic fungi is one of the most devastating diseases, which affects the food safety of the whole world to a great extent. Biological control of plant diseases by microbial natural products is more desirable than traditional chemical control. In this study, we discovered a novel lipopeptide, iturin W, with promising prospects in biological control of plant diseases. Moreover, the effects of different carbon and nitrogen sources and amino acids on production of C14 iturin W and C15 iturin W would provide a reasonable basis for the optimization of the fermentation process of lipopeptides. Notably, the structure of iturin W was different from that of any previously reported lipopeptide, suggesting that deep-sea microorganisms might produce many novel natural products and have significant potential in the development of biological products in the future.

MerF, a proposed bacterial mercury transporter, was surprisingly found to play key roles in the flagellum biogenesis and motility but not mercuric resistance of the deep-sea bacterium Pseudomonas stutzeri 273 in our previous study. However, the mechanism behind this interesting discovery has not been elucidated. Here, we firstly applied the combined transcriptomic and proteomic analysis to the P. stutzeri 273 wild type and merF deletion mutant. The results showed that expressions of extracellular flagellar components and FliS, a key factor controlling the biogenesis of extracellular flagellar filament, were significantly downregulated in the merF deletion mutant. In combination of genetic and biochemical methods, MerF was further demonstrated to regulate the expression of fliS via directly binding to its promoter, which is consistent with the discovery that MerF is essential for bacterial flagellum biogenesis and motility. Importantly, the expression of merF and fliS could be simultaneously upregulated by different heavy metals and MerF homologues exist in both bacterial and archaeal domains. To the best of our knowledge, this is the first report linking the heavy metal transporter and the flagellum biogenesis and motility in microorganisms, which provides a good model to investigate the unexplored adaptation strategies of deep-sea microbes against harsh conditions.

Plant disease caused by pathogenic fungi is one of the most devastating diseases, which affects the food safety of the whole world to a great extent. Biological control of plant diseases by microbial natural products is more desirable than traditional chemical control. In this study, we discovered a novel lipopeptide, iturin W, with promising prospects in biological control of plant diseases. Moreover, the effects of different carbon and nitrogen sources and amino acids on production of C14 iturin W and C15 iturin W would provide a reasonable basis for the optimization of the fermentation process of lipopeptides. Notably, the structure of iturin W was different from that of any previously reported lipopeptide, suggesting that deep-sea microorganisms might produce many novel natural products and have significant potential in the development of biological products in the future., In the present study, a deep-sea bacterial strain designated Bacillus sp. strain wsm-1 was screened and found to exhibit strong antifungal activity against many plant-pathogenic fungi, and corresponding antifungal agents were thereby purified and determined by tandem mass spectrometry to be two cyclic lipopeptide homologs. These homologs, which were different from any previously reported lipopeptides, were identified to possess identical amino acid sequences of β-amino fatty acid-Asn-Ser-Asn-Pro-Tyr-Asn-Gln and deduced as two novel lipopeptides designated C14 iturin W and C15 iturin W. Electron microscopy observation indicated that both iturin W homologs caused obvious morphological changes and serious disruption of plasma membrane toward fungal cells, while C15 iturin W exhibited more serious cell damages than C14 iturin W did, which was well consistent with the results of the antifungal activity assays. To improve the yield and antifungal activity of iturin W, the effects of different carbon and nitrogen sources and amino acids on production of C14 iturin W and C15 iturin W were investigated. The results indicated that supplements of most of the detected carbon and nitrogen sources could increase the yield of C14 iturin W, but inhibit the yield of C15 iturin W, while supplements of tryptone and most of the detected amino acids could increase the yield of both C14 iturin W and C15 iturin W. IMPORTANCE Plant disease caused by pathogenic fungi is one of the most devastating diseases, which affects the food safety of the whole world to a great extent. Biological control of plant diseases by microbial natural products is more desirable than traditional chemical control. In this study, we discovered a novel lipopeptide, iturin W, with promising prospects in biological control of plant diseases. Moreover, the effects of different carbon and nitrogen sources and amino acids on production of C14 iturin W and C15 iturin W would provide a reasonable basis for the optimization of the fermentation process of lipopeptides. Notably, the structure of iturin W was different from that of any previously reported lipopeptide, suggesting that deep-sea microorganisms might produce many novel natural products and have significant potential in the development of biological products in the future.

Supplemental Material, wu_FM_6-18-18_supplemental for Quantifying Energy Consumption in Household Surveys: An Alternative Device-based Accounting Approach by Shimei Wu, Xinye Zheng, Jin Guo, Chuan-Zhong Li and Chu Wei in Field Methods

In addition to the direct energy consumption during the production process, energy-intensive industries can have indirect effects on energy demand because they are upstream industries and have subs...

The energy efficiency of heating systems has become a critical concern for academic study and public welfare worldwide. Developing a comparable measurement tool among various residential space heating systems can offer policy-makers a benchmark for monitoring efficiency, guide them in setting appropriate energy conservation goals and promote overall efficiency improvements through heating system transitions. In the present study, we establish a framework to accommodate heterogenetic space heating systems and model the energy efficiency for performance assessment. By taking the heating area and heating hours into account, two energy intensity indicators are developed. Data from the Chinese Residential Energy Consumption Survey (CRECS) is used to examine the energy intensity for Northern and Southern residences. Our results show opposite findings from other studies, and the interpretation is presented.

Measuring inequality can be challenging due to the limitations of using household income or expenditure data. Because actual energy consumption can be measured more easily and accurately and is relatively more stable, it may be a better measure of inequality. Here we use data on energy consumption for specific devices from a large nation-wide household survey (n = 3,404 rural households from 12 provinces) to assess inequality in rural China. We find that the overall inequality of energy consumption and expenditure varies greatly in terms of energy type, end-use demand, regions and climatic zones. Biomass, space heating and cooking, intraregional differences, and climatic zones characterized as cold or hot summer/cold winter contribute the most to total inequality for each indicator, respectively. The results suggest that the expansion of infrastructure does not accompany alleviation of energy inequality, and that energy affordability should be improved through income growth and targeted safety-net programmes instead of energy subsidies. Inequality in China ranks as one of the highest in the world. Using household energy consumption data, this study shows that deriving energy from biomass, use of energy for space heating and cooking, and intraregional differences are major contributors to consumption inequality in rural China.

In previous research, the full-length sghC1q (CssghC1q) recombinant protein from half-smooth tongue sole (Cynoglossus semilaevis) displayed antibacterial and antiviral activities. However, the roles of the different domains (gC1q and coiled-coil domains) in CssghC1q are still unknown. Thus, in this study, with the help of the pET-28a vector, recombinant proteins comprising different CssghC1q domains were constructed and verified. However, only the recombinant pET-28a-CsgC1q protein was successfully purified. The pET-28a-CsgC1q recombinant protein only exhibited antibacterial activities against Vibrio anguillarum among the bacteria tested. Compared with the full-domain recombinant protein, the recombinant CsgC1q domain exhibited a very low antibacterial activity (10%) at very high protein concentrations (0.1 mg/ml). The CsgC1q protein could show 80% antimicrobial activity against V. anguillarum, though a very high concentration (2.25 mg/ml) was necessary. The CsgC1q protein, which displayed the antibacterial activities, could require its coiled-coil region to promote correct protein folding; thus, without this domain, the protein would fold inefficiently. The results indicate that the CsgC1q domain may be the key antibacterial activities function domain. However, the CsgC1q domain alone is insufficient for proper antibacterial activity. The coiled-coil region, which is located upstream of the CsgC1q domain, might be important for proper folding and antibacterial activities.

Aims Relatively, few anti-biofilm polysaccharides against Pseudomonas aeruginosa were done to investigate the underlying molecular mechanism. Exopolysaccharide EPS273 can clearly reduce biofilm formation and infection of P. aeruginosa. This study aims to investigate its anti-biofilm and anti-infection mechanism on transcriptional level. Methods and results Herein, we used an RNA-Seq transcriptomic approach to investigate the underlying anti-biofilm and anti-infection mechanism of EPS273. The expression levels of a large number of genes were changed after P. aeruginosa PAO1 was treated with EPS273. Especially, the genes related to biofilm formation, such as gene involved in production of extracellular matrix and virulence factor, genes involved in flagella and cell motility and genes involved in iron acquisition. Notably, the expression levels of genes involved in regulatory and signal transduction were markedly downregulated, such as two-component system PhoP-PhoQ and quorum sensing (QS) system LasI/LasR and RhlI/RhlR. Furthermore, when genes phoP and phoQ were disrupted, respectively, the reduction of biofilm formation and cell motility in mutant △phoP or △phoQ was also detected. Conclusion EPS273 may exert its anti-biofilm and anti-infection function by downregulating gene expression of two-component system PhoP-PhoQ and QS systems LasI/LasR and RhlI/RhlR of P. aeruginosa, which further regulated expression of genes involved in biofilm formation. Significance and impact of the study Our data will expand understanding of anti-biofilm mechanisms of polysaccharides on transcriptomic level.

The oceanic response of the Taiwan Strait (TWS) to Typhoon Nesat (2017) was investigated using a fully coupled atmosphere-ocean-wave model (COAWST) verified by observations. Ocean currents in the TWS changed drastically in response to significant wind variation during the typhoon. The response of ocean currents was characterised by a flow pattern generally consistent with the Ekman boundary layer theory, with north-eastward volume transport being significantly modified by the storm. Model results also reveal that the western TWS experienced the maximum generated storm surge, whereas the east side experienced only moderate storm surge. Heat budget analysis indicated that surface heat flux, vertical diffusion, and total advection all contributed to changes in water temperature in the upper 30 m with advection primarily affecting lower depths during the storm. Momentum balance analysis shows that along-shore volume acceleration was largely determined by a combined effect of surface wind stress and bottom stress. Cross-shore directional terms of pressure gradient and Coriolis acceleration were dominant throughout the model run, indicating that the effect of the storm on geostrophic balance was small. This work provides a detailed analysis of TWS water response to typhoon passage across the strait, which will aid in regional disaster management.

This chapter describes and analyzes the residential energy consumption in China in terms of amount and cost of energy and carbon footprint using energy balance and energy flow charts, and compares the residential energy consumption in different regions of China. The analysis and comparison of residential energy consumption in China aims to identify its patterns and influential factors, help decision-makers and the public understand the basic characteristics and geological distribution of residential energy consumption in China and find out the potential, obstacles and influential factors for energy conservation in daily life. The energy sources for household consumption covered in this survey included coal, gasoline, diesel, kerosene, LPG, pipeline natural gas and coal gas, electricity and heat (steam, hot water and hot air for district heating), firewood, straw, solar energy and biogas, etc. Residential energy-consuming activities included cooking, use of household electrical appliances, space heating, water heating and air conditioning. The coefficients for converting consumption of various energy sources to coal equivalent are from the China Energy Statistical Yearbook. In addition, except for the energy balance, energy flow charts and carbon emission tables, the analysis in other sections is based on the calculation results of electrothermal equivalent.

Daily life of households incurs energy consumption to various degrees. Different activities require different energy sources and more than one type of energy sources may be consumed in a single activity.

While the world is going through tremendous changes brought about by informatization, China is also undergoing rapid development driven by urbanization and industrialization, as if it is taking a high-speed train. In the past over 30 years, China has achieved development in economy, society and ecological environment which took advanced economies centuries to achieve. In such a compressed period, the living environment, living conditions and consumption patterns of Chinese residents have also undergone unprecedented changes.

The deep ocean microbiota has unexplored potential to provide enzymes with unique characteristics. In order to obtain cold-active lipases, bacterial strains isolated from the sediment of the deep-sea cold seep were screened, and a novel strain gcc21 exhibited a high lipase catalytic activity, even at the low temperature of 4 °C. The strain gcc21 was identified and proposed to represent a new species of Pseudomonas according to its physiological, biochemical, and genomic characteristics, it was named Pseudomonas marinensis. Two novel encoding genes for cold-active lipases (Lipase 1 and Lipase 2) were identified in the genome of strain gcc21. Genes encoding Lipase 1 and Lipase 2 were respectively cloned and overexpressed in E. coli cells, and corresponding lipases were further purified and characterized. Both Lipase 1 and Lipase 2 showed an optimal catalytic temperature at 4 °C, which is much lower than those of most reported cold-active lipases, but the activity and stability of Lipase 2 were much higher than those of Lipase 1 under different tested pHs and temperatures. In addition, Lipase 2 was more stable than Lipase 1 when treated with different metal ions, detergents, potential inhibitors, and organic solvents. In a combination of mutation and activity assays, catalytic triads of Ser, Asp, and His in Lipase 1 and Lipase 2 were demonstrated to be essential for maintaining enzyme activity. Phylogenetic analysis showed that both Lipase 1 and Lipase 2 belonged to lipase family III. Overall, our results indicate that deep-sea cold seep is a rich source for novel bacterial species that produce potentially unique cold-active enzymes.

Sulfur cycling is primarily driven by sulfate reduction mediated by sulfate-reducing bacteria (SRB) in marine sediments. The dissimilatory sulfate reduction drives the production of enormous quantities of reduced sulfide and thereby the formation of highly insoluble metal sulfides in marine sediments. Here, a novel sulfate-reducing bacterium designated Pseudodesulfovibrio cashew SRB007 was isolated and purified from the deep-sea cold seep and proposed to represent a novel species in the genus of Pseudodesulfovibrio. A detailed description of the phenotypic traits, phylogenetic status and central metabolisms of strain SRB007 allowed the reconstruction of the metabolic potential and lifestyle of a novel member of deep-sea SRB. Notably, P. cashew SRB007 showed a strong ability to resist and remove different heavy metal ions including Co2+, Ni2+, Cd2+ and Hg2+. The dissimilatory sulfate reduction was demonstrated to contribute to the prominent removal capability of P. cashew SRB007 against different heavy metals via the formation of insoluble metal sulfides.

An extracellular alkaline protease produced by marine bacteria strain Pseudoalteromonas sp. 129-1 was purified by ammonium sulphate precipitation, anion exchange chromatography, and gel filtration. The purity of the protease was confirmed by SDS-PAGE and molecular mass was estimated to be 35kDa. The protease maintained considerable activity and stability at a wide temperature range of 10-60 degrees C and pH range of 6-11, and optimum activity was detected at temperature of 50 degrees C and pH of 8. Metallo-protease inhibitor, EDTA, had no inhibitory effect on protease activity even at concentration up to 15mM, whereas 15mM PMSF, a common serine protease inhibitor, greatly inactivated the protease. The high stability of the protease in the presence of surfactants (SDS, Tween 80, and Triton X-100), oxidizing agent H2O2, and commercial detergents was observed. Moreover, the protease was tolerant to most of the tested organic solvents, and saline tolerant up to 30%. Interestingly, biofilm of Pseudomonas aeruginosa PAO1 was greatly reduced by 0.01mgml(-1) of the protease, and nearly completely abolished with the concentration of 1mgml(-1). Collectively, the protease showed valuable feathers as an additive in laundry detergent and non-toxic anti-biofilm agent.

Calcium carbonate (CaCO3) biomineralization has been investigated due to its wide range of scientific and technological implications, however, the molecular mechanisms of this important geomicrobiological process are largely unknown. Here, a urease-positive marine actinobacterium Brevibacterium linens BS258 was demonstrated to effectively form CaCO3 precipitates. Surprisingly, this bacterium could also dissolve the formed CaCO3 with the increase of the Ca2+ concentration. To disclose the mechanisms of biomineralization, the genome of B. linens BS258 was further completely sequenced. Interestingly, the expression of three carbonic anhydrases was significantly up-regulated along with the increase of Ca2+ concentration and the extent of calcite dissolution. Moreover, transcriptome analyses revealed that increasing concentration of Ca2+ induced KEGG pathways including quorum sensing (QS) in B. linens BS258. Notably, most up-regulated genes related to QS were found to encode peptide/nickel ABC transporters, which suggested that nickel uptake and its associated urease stimulation were essential to boost CaCO3 biomineralization. Within the genome of B. linens BS258, there are both cadmium and lead resistance gene clusters. Therefore, the sequestration abilities of Cd2+ and Pb2+ by B. linens BS258 were checked. Consistently, Pb2+ and Cd2+ could be effectively sequestered with the precipitation of calcite by B. linens BS258. To our knowledge, this is the first study investigating the microbial CaCO3 biomineralization from both genomic and transcriptomic insights, which paves the way to disclose the relationships among bacterial metabolisms and the biomineralization.

Calcium carbonate (CaCO3) biomineralization has been investigated due to its wide range of scientific and technological implications, however, the molecular mechanisms of this important geomicrobiological process are largely unknown. Here, a urease-positive marine actinobacterium Brevibacterium linens BS258 was demonstrated to effectively form CaCO3 precipitates. Surprisingly, this bacterium could also dissolve the formed CaCO3 with the increase of the Ca2+ concentration. To disclose the mechanisms of biomineralization, the genome of B. linens BS258 was further completely sequenced. Interestingly, the expression of three carbonic anhydrases was significantly up-regulated along with the increase of Ca2+ concentration and the extent of calcite dissolution. Moreover, transcriptome analyses revealed that increasing concentration of Ca2+ induced KEGG pathways including quorum sensing (QS) in B. linens BS258. Notably, most up-regulated genes related to QS were found to encode peptide/nickel ABC transporters, which suggested that nickel uptake and its associated urease stimulation were essential to boost CaCO3 biomineralization. Within the genome of B. linens BS258, there are both cadmium and lead resistance gene clusters. Therefore, the sequestration abilities of Cd2+ and Pb2+ by B. linens BS258 were checked. Consistently, Pb2+ and Cd2+ could be effectively sequestered with the precipitation of calcite by B. linens BS258. To our knowledge, this is the first study investigating the microbial CaCO3 biomineralization from both genomic and transcriptomic insights, which paves the way to disclose the relationships among bacterial metabolisms and the biomineralization.

This study was initiated to screen for marine bacterial agents to biocontrol Magnaporthe grisea, a serious fungal pathogen of cereal crops. A bacterial strain, isolated from the cold seep in deep sea, exhibited strong growth inhibition against M. grisea, and the strain was identified and designated as Bacillus sp. CS30. The corresponding antifungal agents were purified by acidic precipitation, sequential methanol extraction, Sephadex LH-20 chromatography, and reversed phase high-performance liquid chromatography (RP-HPLC), and two antifungal peaks were obtained at the final purification step. After analysis by mass spectrometry (MS) and tandem MS, two purified antifungal agents were deduced to belong to the surfactin family, and designated as surfactin CS30-1 and surfactin CS30-2. Further investigation showed that although the antifungal activity of surfactin CS30-1 is higher than that of surfactin CS30-2, both of them induced the increased generation of reactive oxygen species (ROS) and caused serious damage to the cell wall and cytoplasm, thus leading to the cell death of M. grisea. Our results also show the differences of the antifungal activity and antifungal mechanism of the different surfactin homologs surfactin CS30-1 and surfactin CS30-2, and highlight them as potential promising agents to biocontrol plant diseases caused by M. grisea.

Many polysaccharides isolated from plants have exhibited promising antitumor activities. The aim of this study is to investigate the antitumor activity of the novel polysaccharide named SPS from Sargassum integerrimum, elucidate the underlying anticancer mechanism in a human lung cancer cell line A549 and evaluate its anti-angiogenic activity both in vitro and in vivo. The results show that SPS significantly reduces A549 cells viability in a dose- and time-dependent manner via MTT method. Flow cytometry analysis indicates that SPS could induce cell apoptosis, the loss of mitochondrial membrane potential (MMP), generation of reactive oxygen species (ROS) and G2/M phase cell cycle arrest of A549 cells. Up-regulation of the expressions of P53 and Bax, down-regulation of the expression of Bcl-2 and activation of cleaved caspase-3, caspase-9 and PARP are also detected by western blotting after the treatment of SPS. In addition, SPS inhibits the proliferation, migration and cord formation of human umbilical vein endothelial cells (HUVECs) in vitro and prevents the vascular development of zebrafish embryos in vivo. Altogether, our data prove the anticancer and anti-angiogenesis properties of SPS and provide further insights into the potential pharmacological application of SPS as antitumor and anti-angiogenic agent against lung cancer.

A multifunctional enzyme is one that performs multiple physiological functions, thus benefiting the organism. Characterization of multifunctional enzymes is important for researchers to understand how organisms adapt to different environmental challenges. In the present study, we report the discovery of a novel multifunctional enzyme Amy63 produced by marine bacterium Vibrio alginolyticus 63. Remarkably, Amy63 possesses amylase, agarase and carrageenase activities. Amy63 is a substrate promiscuous α-amylase, with the substrate priority order of starch, carrageenan and agar. Amy63 maintains considerable amylase, carrageenase and agarase activities and stabilities at wide temperature and pH ranges and optimum activities are detected at temperature of 60 °C and pH of 6.0, respectively. Moreover, the heteroexpression of Amy63 dramatically enhances the ability of E. coli to degrade starch, carrageenan and agar. Motif searching shows three continuous glycosyl hydrolase 70 (GH70) family homologs existed in Amy63 encoding sequence. Combining serial deletions and phylogenetic analysis of Amy63, the GH70 homologs are proposed as the determinants of enzyme promiscuity. Notably, such enzymes exist in all kingdoms of life, thus providing an expanded perspective on studies of multifunctional enzymes. To our knowledge, this is the first report of an amylase having additional agarase and carrageenase activities.

An extracellular alkaline protease produced by marine bacteria strain Pseudoalteromonas sp. 129-1 was purified by ammonium sulphate precipitation, anion exchange chromatography, and gel filtration. The purity of the protease was confirmed by SDS-PAGE and molecular mass was estimated to be 35 kDa. The protease maintained considerable activity and stability at a wide temperature range of 10-60 °C and pH range of 6-11, and optimum activity was detected at temperature of 50 °C and pH of 8. Metallo-protease inhibitor, EDTA, had no inhibitory effect on protease activity even at concentration up to 15 mM, whereas 15 mM PMSF, a common serine protease inhibitor, greatly inactivated the protease. The high stability of the protease in the presence of surfactants (SDS, Tween 80, and Triton X-100), oxidizing agent H(2)O(2), and commercial detergents was observed. Moreover, the protease was tolerant to most of the tested organic solvents, and saline tolerant up to 30%. Interestingly, biofilm of Pseudomonas aeruginosa PAO1 was greatly reduced by 0.01 mg ml(-1) of the protease, and nearly completely abolished with the concentration of 1 mg ml(-1). Collectively, the protease showed valuable feathers as an additive in laundry detergent and non-toxic anti-biofilm agent.

Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus are key factors in the fermentation process and the final quality of dairy products worldwide. This study was performed to investigate the effects of the proportions of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus isolated from traditionally fermented dairy products in China and Mongolia on the profile of volatile compounds produced in samples. Six proportional combinations (1:1, 1:10, 1:50, 1:100, 1:1000, and 1:10,000) of L. delbrueckii subsp. bulgaricus IMAU20401 to S. thermophilus ND03 were considered, and the volatiles were identified and quantified by solid-phase microextraction and gas chromatography–mass spectrometry (SPME-GC-MS) against an internal standard. In total, 89 volatile flavor compounds, consisting of aldehydes, ketones, acids, alcohols, esters, and aromatic hydrocarbons, were identified. Among these, some key flavor volatile compounds were identified, including acetaldehyde, 3-methylbutanal, acetoin, 2-heptanone, acetic acid, butanoic acid, and 3-methyl-1-butanol. The of L. delbrueckii subsp. bulgaricus IMAU20401 to S. thermophilus ND03 influenced the type and concentration of volatiles produced. In particular, aldehydes and ketones were present at higher concentrations in the 1:1000 treatment combination than in the other combinations. Our findings emphasize the importance of selecting the appropriate proportions of L. delbrueckii subsp. bulgaricus and S. thermophilus for the starter culture in determining the final profile of volatiles and the overall flavor of dairy products.

Pseudomonas stutzeri 273 is a marine bacterium producing exopolysaccharide 273 (EPS273) with high anti-biofilm activity against P. aeruginosa PAO1. Here, the complete genome of P. stutzeri 273 was sequenced and the genome contained a circular 5.03 Mb chromosome. With extensive analysis of the genome, a genetic locus containing 18 genes was predicted to be involved in the biosynthesis of EPS273. In order to confirm this prediction, two adjacent genes (eps273-H and eps273-I) encoding glycosyltransferases and one gene (eps273-O) encoding tyrosine protein kinase within the genetic locus were deleted and biosynthesis of EPS273 was checked in parallel. The molecular weight profile of EPS purified from the mutant Δeps273-HI was obviously different from that purified from wild-type P. stutzeri 273, while the corresponding EPS was hardly detected from the mutant Δeps273-O, which indicated the involvement of the proposed 18-gene cluster in the biosynthesis of EPS273. Moreover, the mutant Δeps273-HI had the biofilm formed earlier compared with the wild type, and the mutant Δeps273-O almost completely lost the ability of biofilm formation. Therefore, EPS273 might facilitate the biofilm formation for its producing strain P. stutzeri 273 while inhibiting the biofilm formation of P. aeruginosa PAO1. This study can contribute to better understanding of the biosynthesis of EPS273 and disclose the biological function of EPS273 for its producing strain P. stutzeri 273.

A cDNA expression library from Brassica juncea was introduced into the fission yeast Schizosaccharomyces pombe to select for transformants tolerant to cadmium. Transformants expressing OXIDATIVE STRESS 3 (OXS3) or OXS3-Like cDNA exhibited enhanced tolerance to a range of metals and oxidizing chemicals. OXS3 belongs to a family of proteins that share a highly conserved domain corresponding to a putative N-acetyltransferase or thioltransferase catalytic site. Mutations within this conserved domain abolished the ability of Arabidopsis thaliana OXS3 to enhance stress tolerance in S. pombe, indicating a role in stress tolerance for the presumptive catalytic domain. A stress-sensitive mutant of AtOXS3 and enhanced tolerance of overexpression lines support the role of OXS3 in stress tolerance. The expression of tagged B. juncea and A. thaliana OXS3 proteins in plant cells revealed a subnuclear speckling pattern related to the nucleosome in discrete parts of the chromatin. It is possible that OXS3 might act as a chromatin remodeling factor for the stress response.

Subpeptin JM4-A and subpeptin JM4-B are two novel antimicrobial peptides produced by Bacillus subtilis JM4. To identify putative genes involved in their production, degenerate PCR primers targeted to conserved motifs of nonribosomal peptide synthetases (NRPSs) were used. A resulting 1.2 kb PCR product had high sequence similarity to genes of NRPSs, and then a 2.8 kb DNA fragment flanking it was cloned subsequently. Gene disruption of the resulting 4 kb DNA fragment produced subpeptin-deficient mutant, suggesting that subpeptin JM4-A and subpeptin JM4-B were biosynthesized by NRPSs. Based on this result, a 48 kb gene cluster was cloned, which consisted of nine coding sequences (CDSs) involved in antimicrobial peptide biosynthesis, regulation, and resistance. Disruption of two relatively large CDSs subA and subC led to subpeptin-deficient mutants, which supported the involvement of the cloned gene cluster in subpeptin biosynthesis.