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A stable fluorescent holo-β-allophycocyanin (holo-ApcB) was produced by metabolically engineeredEscherichia coli. TheE. colicells harbored two plasmids for expression of five genes that were involved in the holo-ApcB production. Response surface methodology was employed to investigate the individual and interactive effects of four variables, i.e., initial pH of culture medium, IPTG concentration, post-induction temperature, and induction start time, on holo-ApcB production byE. coli. The experimental results showed that the IPTG concentration, postinduction temperature, and induction start time had significant individual effects on holo-ApcB production. A significant interactive effect was also found between the initial pH of culture and induction start time. The maximum holo-ApcB production of 45.3 mg/L was predicted under the following optimized culture conditions: a postinduction temperature of 28.4°C, initial pH of culture of 7.3, IPTG concentration of 1.1 mM, and postinduction time of 66 min. Holo-ApcB production under the optimized culture conditions increased 5.8-fold, compared with that under the nonoptimized conditions. Response surface methodology proved to be a valuable tool for optimization of holo-ApcB production by metabolically engineeredE. coli. [ABSTRACT FROM PUBLISHER]

Edwardsiella tarda and Vibrio anguillarum are the two main pathogenic bacteria that cause edwardsiellosis and vibriosis in various species of fish raised in aquaculture. In our previous study, the live attenuated vaccines E. tarda WED and V. anguillarum MVAV6203 showed robust relative protection when vaccinated zebrafish or turbot were challenged with virulent E. tarda or V. anguillarum , respectively . Additionally, vaccinated fish processed the two vaccines through different pathways of antigen processing and presentation. Here, the immune protection of a combination vaccination consisting of E. tarda WED and V. anguillarum MVAV6203 was initially evaluated in zebrafish. After challenge with E. tarda and V. anguillarum at 1 month post-vaccination, the vaccinated zebrafish exhibited the relative protective survival of 70% and 90%, respectively. The expression of genes related to antigen recognition, processing and presentation were measured in the liver and spleen of vaccinated zebrafish. Gene expression profiling showed that more than one Toll-like receptor signaling pathway was activated and that both MHC I and II pathways of antigen processing and presentation were evoked. Later, the immune protection of the combination vaccine was evaluated in turbot and it showed similarly effective immune-mediated protection. By ELISA analysis, we found that the specific antibody levels in vaccinated turbot increased compared to those of fish vaccinated by a single vaccine during 2 months post-vaccination. Meanwhile, the expression levels of MHC I and II in the liver, spleen and kidney of vaccinated turbot were both up-regulated, suggesting that the MHC I and II pathways of antigen processing and presentation are activated in vaccinated turbot, similar to vaccinated zebrafish. In summary, a combination vaccine of live attenuated E. tarda WED and V. anguillarum MVAV6203 is effective and could be used widely in the future. [ABSTRACT FROM AUTHOR]

Disease is one of the most critical factors restricting the green and sustainable development of aquaculture. Microalgae, serving as excellent aquatic bait with high nutritional value, can strengthen the immune protection of aquatic organisms. The purpose of this study is to select superior marine microalgae to as feed additives that can defend against pathogens to a certain extent. In this study, the nutrient compositions of three marine microalga species were analyzed, and their antioxidant and innate-immunity protection effects as feed additions on Danio rerio were further investigated. Results demonstrated that Dunaliella salina contained 36.72% carbohydrates, 0.51% total chlorophyll, and 1.20% total carotenoids. Isochrysis galbana contained 1.33% total chlorophyll and 0.91% total carotenoids. The total fatty acid content of Phaeodactylum tricornutum and I. galbana was 60.77 μg mg−1 dry cell weight (DCW) and 76.40 μg mg−1 DCW, respectively. The docosahexaenoic acid content of I. galbana was 8.57 μg mg−1 DCW. After 30 days of feeding with different diets on D. rerio , the relative percent survival of the D. salina and I. galbana group challenged with Edwardsiella tarda EIB 202 were 17.39% and 26.09%, respectively. In the I. galbana group, the relative expression levels of the antioxidant factor catalase and glutathione peroxidase increased 1.5–2.5 times. Furthermore, the Toll-like receptors 2 signaling pathway was activated, and the signaling transcription-factor nuclear factor kappa-B was activated depending on the myeloid differentiation factor 88 pathway to promote cytokine expression. The relative expression of defensins increased 1.26 times, which helped enhance the innate-immunity defense system. Therefore, I. galbana can be developed as feed additives in the freshwater-fish field and be an excellent carrier for the development of recombinant microalga vaccine in aquaculture. • Three marine microalgae were investigated as nutritional supplements for zebrafish. • Marine microalgae are rich in nutrients like carbohydrates, pigments and PUFAs. • Isochrysis galbana showed the best challenge protection efficiency against E. tarda. • Expression of antioxidant and immune factors were increased by microalgae powders. [ABSTRACT FROM AUTHOR]

Background: A candidate vaccine, live attenuated Vibrio anguillarum developed in our laboratory could prevent vibriosis of fish resulted from V. anguillarum and V. alginolyticus. To elucidate the molecular mechanisms underlying the vaccine protection, we used microarray technology to compare the spleen transcriptomes of bath-vaccinated and unvaccinated zebrafish at 28 days post vaccination. Principal Findings: A total of 2164 genes and transcripts were differentially expressed, accounting for 4.9% of all genes represented on the chip. In addition to iron metabolism related to the innate immunity and the signaling pathways, these differentially expressed genes also involved in the adaptive immunity, mainly including the genes associated with B and T cells activation, proliferation and expansion. Transcription profiles of Th17-related transcription factors, cytokines and cytokine receptors during 35 days post-vaccination implied that Th17 cells be activated in bath-vaccinated zebrafish. Conclusion/Significance: The transcriptome profiling with microarray revealed the Th17-like immune response to bath-vaccination with the live attenuated V. anguillarum in zebrafish. [ABSTRACT FROM AUTHOR]

Abstract: Live attenuated vaccines are a promising application to control bacterial fish diseases. A live attenuated Vibrio anguillarum vaccine candidate was established in our laboratory to protect fish against vibriosis. To elucidate the mechanism of immunoprotection, it is necessary to compare the different immune responses to infection between vaccinated and non-vaccinated fish. In this study, the expression levels of pathogen-specific antibodies and immune-related genes upon challenge at 28 days post-vaccination were compared between vaccinated and non-vaccinated zebrafish. In the results, the specific antibody levels against virulent V. anguillarum in the vaccinated group did not rise significantly following infection, which suggested that high-affinity antibodies were induced by the vaccine. In the non-vaccinated group, the specific IgM response was triggered at 3 days post-infection and showed a delayed antibody response. Meanwhile, the transcription levels of the genes encoding the pro-inflammatory cytokine IL-1β and the chemokine IL-8 were more highly up-regulated in non-vaccinated fish than in vaccinated fish. This suggests that the overwhelming inflammatory response trigged by infection in non-vaccinated zebrafish was controlled in vaccinated zebrafish. Interestingly, the expression levels of adaptive immune-related genes were increased in vaccinated fish after challenge, compared to the non-vaccinated fish. These results suggest that inoculation with the live attenuated vaccine triggered protection by curbing inflammation and strengthening the adaptive immune response. [Copyright &y& Elsevier]

Yak down and brown cashmere share a high similarity in morphological appearance, so that either bleached or dyed samples might not be differentiated visually. False declaration and adulteration with relatively cheap yak down is quite common in brown cashmere products due to the lure of high profits. We provide a novel and effective method based on deoxyribonucleic acid analysis technology to identify yak down by designing a set of TaqMan minor groove binder polymerase chain reaction primers and a probe that can react specifically to the yak 12S ribosomal ribonucleic acid gene. The method can be applied directly to identify yak fiber products and to examine the quality of cashmere products. [ABSTRACT FROM PUBLISHER]

Abstract: Edwardsiella tarda is a Gram-negative pathogen which causes systemic infection in turbot. The increasing frequency of edwardsiellosis in turbot farming has stressed the need to understand the immune responses of fish, for the further development of prevention and control strategies. As a broad spectrum protective antigen, a recombinant glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of E. tarda EIB202 has been proven to present remarkable protection against E. tarda, Aeromonas hydrophila, Vibrio anguillarum, Vibrio alginolyticus and Vibrio harvei in zebrafish. Here, the protection and immune responses of turbot vaccinated with this antigen were studied. Fish vaccinated with recombinant GAPDH via intraperitoneal injection exhibited a low cumulative mortality when challenged with E. tarda EIB202, while high levels of specific antibodies and enhanced bactericidal activities of the immunized sera were observed. In addition, significantly increased transcription levels of four immune-related genes including IL-1β, MHC Iα and IIα, and IgM in the liver, spleen and kidney tissues of vaccinated fish showed that both humoral and cellular immune responses were soundly aroused in the vaccinated fish. Moreover, the IgM antibodies induced by recombinant GAPDH exhibited obvious cross-reactions with the other four pathogens. These results suggested that recombinant GAPDH could present effective protective immunity not only against E. tarda but also other extracellular pathogens, and would be a potential vaccine candidate against polymicrobial infections in the aquaculture industry. [Copyright &y& Elsevier]

Open innovation has become an important mode for firms to improve innovation performance. If the openness is too low, it will reduce the opportunity to acquire external knowledge, while too open will increase the risk of internal knowledge leakage. Therefore, the degree of openness plays a key role in the use of open innovation to improve innovation performance. We use the openness breadth and openness depth to describe the openness of innovation. We conduct an agent-based simulation methodology to study the optimal degree of openness. Our findings show that there are great differences in the optimal degree of openness under different situations. Moreover, as the situation changes, the optimal degree of openness changes regularly. More specifically, the more a firm's knowledge network structure holes, the smaller the optimal openness breadth and the greater the optimal openness depth. The higher a firm's knowledge network centrality, the greater the optimal openness breadth and the smaller the optimal openness depth. The worse the institutional environment, the smaller the optimal openness breadth and openness depth. The fiercer the market competition, the greater the optimal openness breadth and the smaller the optimal openness depth. • Openness affects the knowledge acquisition and knowledge leakage, thereby affecting innovation performance. • The agent-based simulation methodology is conducted to study the optimal degree of openness in open innovation. • The optimal breadth and depth of openness are greatly different under different situations. • As the situation changes, the optimal degree of openness changes regularly. [ABSTRACT FROM AUTHOR]

Microalgae can accumulate large amounts of nutrients from sustainable elements cycling and wastewater reuse. Light is a key factor determining productivity of algal biomass when recycling. However, light is unevenly distributed in photobioreactors due to light absorption and scatter by algal cells. Understanding the laws of light distribution is needed for optimizing the culture process. In this study, a light distribution model for red alga Porphyridium purpureum was used to optimize the cultivation process and improve culture performance by controlling light intensity. Compared to the Lambert-Beer model, the Hyperbolic law is more flexible and is applicable in a larger range of cell densities. In addition, the content of intracellular phycobiliprotein has a great influence on light distribution inside the photobioreactor while a higher biomass concentration reduces its impact. A maximum biomass concentration of 24.7 g/L along with 1.2 g/L/d cell growth rate was achieved by increasing incident light intensity in a stepwise fashion. The overall light conditions inside the photobioreactor during the culture process was also analyzed and discussed based on light distribution models. A volume-averaged light intensity regulated at ~50 μmol/m2/s along with an incident light intensity of less than 540 μmol/m2/s is an appropriate light condition for Porphyridium purpureum culture. The outcomes of light distribution model assessment and stepwise fashion regulation strategy can be applied to red microalgae in general, especially for high cell density cultivation. These findings provide an essential base for culture optimization, which can be used in future industrial applications of P. purpureum for water clean and sustainability of human nourishment production. [Display omitted] • The light attenuation profiles were measured under different conditions. • Two light distribution models were compared and validated. • The volume-averaged light intensity was regulated along with incident light intensity. • The maximum biomass concentration of 24.7 g/L along with 1.2 g/L/d cell growth rate was achieved. • The outcomes of light distribution model assessment can be applied to red microalgae in general. [ABSTRACT FROM AUTHOR]

A novel Gram-stain-positive, aerobic, catalase-positive, oxidase-negative, non-motile, and rod-shaped bacterium with ibuprofen-degrading capacity, designated DM4T, was isolated from the sewage of a wastewater treatment plant (WWTP) in Guangzhou city, China. Strain DM4T grew optimally at 0% (w/v) NaCl, pH 5.0–7.0, and 30 °C, forming white colonies on trypticase soy agar. C18:1ω9c, C18:2ω9.12c and C15:1ω10c were the predominant fatty acids. Results of 16S rRNA gene alignment and phylogenetic analysis indicated that strain DM4T belonged to the genus Patulibacter, was closely related to Patulibacter medicamentivorans DSM 25692T (98.5%) and P. brassicae KCTC 39817T (98.1%). Strain DM4T had a genome size of 5.33Mbp, and the DNA G + C content was 75.0%. The average nucleotide identity (ANI), average amino acid identity (AAI), and digital DNA–DNA hybridisation (dDDH) values between strain DM4T and P. medicamentivorans were 85.2%, 83.9%, and 29.0% respectively, while those between strain DM4T and P. brassicae were 78.5%, 71.3%, and 22.2%, respectively. Strain DM4T could significantly degrade ibuprofen by almost 80% after 84 h of incubation, and the degradation kinetics was well fitted with the first-order kinetics. Evidence from phenotypic, phylogenetic and chemotaxonomic analyses support that strain DM4T (= GDMCC 1.4574T = KCTC 59145T) represents a new species of the genus Patulibacter, for which the name Patulibacter defluvii sp. nov. is proposed. [ABSTRACT FROM AUTHOR]

A series of environmental issues caused by excessive energy consumption in the transportation industry have hindered China's sustainable development. In this study, an emergy synthesis method was used to analyze the flow of energy. Meanwhile, the emergy yield rate (EYR), environmental load rate (ELR) and emergy sustainability index (ESI) were calculated to evaluate the economic and environmental benefits of the system. In addition, we applied system dynamics to provide a scenario simulation method to compare the emergy indicators of the framework implemented. The paper further put forward some policy insights to improve the sustainability of the transportation system, including adjusting the transportation structure, increasing renewable energy use and promoting a circular economy. The scenario simulation framework based on the sustainable development model of emergy flow can provide a reference for the green development of transportation systems in other regions. [ABSTRACT FROM AUTHOR]

There are two problems in biological treatment of coking wastewater (CWW): incapability of pre-anaerobic treatment to eliminate the toxicity in wastewater, and the lack of carbon source for subsequent denitrification in pre-aerobic treatment. To achieve simultaneous decarburization, nitrification and denitrification (SDCND) in CWW treatment, biological carrier materials was used to build an integrated fluidized-bed reactor (Reactor B, RB). A conventional fluidized-bed reactor (Reactor A, RA) was used as a control reactor under the same condition. The results showed that RB was more advantageous since its removal efficiencies of COD and TN were 90% and 87%, respectively, which were significantly higher than these in RA (82% and 45%), at a hydraulic retention time (HRT) of 60 h. Microelectrode measurement indicated that oxygen transfer was limited inside the carrier where the formation of a dissolved oxygen (DO) concentration gradient was observed. Microbial community analysis showed that the aerobic and anoxic microenvironments in RB promoted the co-existence of a wider variety of bacteria, thus achieving SDCND. These results indicated the integrated fluidized-bed reactor exhibited promising feasibility for simultaneous carbon and nitrogen removal in CWW treatment under the same aeration driven conditions. The SDCND process realized by fluidized-bed reactor provided a reference for the treatment of toxic industrial wastewater with high carbon to nitrogen ratio. Image 1 • Differential distribution of DO was achieved via the addition of carrier. • Efficient SDCND was accomplished in a single reactor. • The TN removal reached 87%, doubled that of the control reactor. • The carrier supported aerobic and anoxic environments for various bacteria. [ABSTRACT FROM AUTHOR]

Cyanide is a typical toxic reducing agent prevailing in wastewater with a well-defined chemical mechanism, whereas its exploitation as an electron donor by microorganisms is currently understudied. Given that conventional denitrification requires additional electron donors, the cyanide and nitrogen can be eliminated simultaneously if the reducing HCN/CN− and its complexes are used as inorganic electron donors. Hence, this paper proposes anaerobic cyanides oxidation for nitrite reduction, whereby the biological toxicity and activity of cyanides are modulated by bimetallics. Performance tests illustrated that low toxicity equivalents of iron-copper composite cyanides provided higher denitrification loads with the release of cyanide ions and electrons from the complex structure by the bimetal. Both isotopic labeling and Density Functional Theory (DFT) demonstrated that CN−-N supplied electrons for nitrite reduction. The superposition of chemical processes reduces the biotoxicity and enhances the biological activity of cyanides in the CN−/Fe3+/Cu2+/ NO 2 – coexistence system, including complex detoxification of CN− by Fe3+, CN− release by Cu2+ from [Fe(CN) 6 ]3−, and NO release by nitrite substitution of −CN groups. Cyanide is the smallest structural unit of C/N-containing compounds and serves as a probe to extend the electron-donating principle of anaerobic cyanides oxidation to more electron-donor microbial utilization. [Display omitted] • A novel anaerobic cyanides oxidation and its metabolic pathway were found. • Complex detoxification of coexisting systems facilitates cyanide metabolisms. • Bimetallic modulation promotes the cyanide detoxification and electron release. • The probing role of cyanides reveals the bioavailability of N-containing compounds. [ABSTRACT FROM AUTHOR]

A novel full-scale prefix oxic coking wastewater (CWW) biological treatment O/H/O system had been operated steadily six years with the effluent quality meeting national discharge standard. Comparing to the traditional CWW biological treatment process, which usually have an anaerobic unit at the start of the process, here the O/H/O system has obvious advantages in COD removal, total nitrogen removal and reduced energy consumption. It is very necessary to illustrate the structure and function of the microbial community involved in different bioreactors of the O/H/O system. High-throughput MiSeq sequencing was used to examine the 16S rRNA genes in this system. Results revealed a contrasting microbial composition among the activated sludge samples of three sequential bioreactors: the β-Proteobacteria related sequences dominated in the O 1 activated sludge with the relative abundance of 56.44% while 7.53% of the sequences were assigned to Thiobacillus ; Rhodoplanes related sequences dominated in the bioreactor H and O 2 activated sludge with relative abundance of 8.86% and 8.92%, respectively. The physico-chemical characteristics of CWW were analyzed by standard methods and the operational parameters were routinely monitored to examine their effects on the microbial communities. The bioinformatics software package of phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) was used to predict the microbial community functional profiling and found three dominant genera of Rhodoplanes, Lysobacter and Leucobacter enriched the xenobiotics biodegradation and metabolism pathway. The diverse and distinct microbial community involved in biological treatment processes of CWW treatment indicating that water characteristics and operational parameters determined the microbial community composition. These results significantly expanded our knowledge of the biodiversity and population dynamics of microorganisms and discerned the relationships between bacterial communities and environmental variables in the biological treatment processes. Moreover, in this study, we proposed a comprehensive biodegradation model of CWW treatment and defined as O/H/O system. Image 1 • Microbiology in a novel CWW treatment O/H/O system was studied by metagenomics. • The bacterial diversity increased with the biological treatment progress of O/H/O. • The family of Comamonadaceae perform the major function of decarburization in O 1. • The dominant genera enriched the xenobiotics biodegradation and metabolism pathway. • A comprehensive biodegradation model of CWW treatment was proposed. [ABSTRACT FROM AUTHOR]

Based on the actual situation of the knowledge flow during industrial transfer, a dynamic model of knowledge flow in a complex network is built. The mechanism of the knowledge flow in the network is analysed, and an analogue simulation is conducted using the Netlogo platform to identify the effects of the network's average degree, the number of enterprises involved in the transfer, the network size, and the effective transmission rate of the knowledge on the efficiency of the knowledge flow in the network. According to the final steady state of the knowledge, the technology spillover effect of the industrial transfer is then discussed. The research results show that the average degree of the network, the number of enterprises involved in the transfer, and the effective transmission rate of the knowledge have significant influences on the efficiency of the knowledge flow in the network, and increasing the network size is beneficial to increasing the number of final knowledge owners. Thus, the final steady state of the knowledge flow plays a decisive role in the technology spillover effect of industrial transfer. [ABSTRACT FROM AUTHOR]

• A material inter-recycling concept for treating wastewater containing S and N. • Fe2+ to precipitate and recover S2− as electron donor for autotrophic denitrification. • Precipitated FeS is more efficient as an electron donor than the commercial one. • Enhanced removal of inert COD from the secondary effluent of coking wastewater. • Significant NO 2 −-N accumulation was observed with FeS as an electron donor. For wastewaters containing high strength sulfide and nitrogen (e.g. coking wastewater), sulfide might be precipitated and recovered using ferrous salt. This study systematically investigated the feasibility of recovered and precipitated FeS (comparing to commercial FeS minerals) to support autotrophic denitrification for advance nitrogen removal from bio-treated coking wastewater in fluidized bed reactors. The reactor with precipitated FeS could achieve simultaneous removal of NO 3 −-N and inert COD with high efficiencies of around 96.3% and 30.5%, at NO 3 −-N and COD loading rates of 4.18 mg·L−1·h−1 and 8.06 mg·L−1·h−1, respectively. Whereas, the performance of commercial FeS reduced gradually and irreversibly after two days, which became completely ineffective after 40 days. Thiobacillus and Rhodanobacter dominated the biomass, which played a key role in the FeS-based denitrification process. This material inter-recycling concept benefits an advance and more sustainable treatment of wastewaters with high strength sulfide and nitrogen. [ABSTRACT FROM AUTHOR]

Cryptosporidium parvum is a protozoan parasite that can cause moderate-to-severe diarrhea. Insulinase-like proteases (INS) are one of the largest protein families within the small proteome of the pathogen. However, their roles in C. parvum biology remain un-elucidated. In this study, a member of the protein family, INS-15 of C. parvum encoded by cgd3_4260, was cloned, expressed and characterized to understand its function. INS-15 and its domain I were expressed in Escherichia coli and polyclonal antibodies against the domain I and one specific polypeptide were prepared in rabbits. The role of INS-15 protein in the C. parvum invasion was preliminarily studied. Recombinant INS-15 protein and its domain I were successfully expressed in E. coli, together with various degraded products. The cgd3_4260 gene had a peak expression at 2 h of in vitroC. parvum culture, while the INS-15 protein was expressed in the mid-anterior region of sporozoites and the area of merozoites opposite to the nucleus. Anti-INS-15 domain I antibodies reduced the invasion of C. parvum sporozoites by over 40%. The anterior location of INS-15 in invasion stages and partial reduction of in vitro growth indicate that INS-15 plays some roles in the invasion or early development of C. parvum. [ABSTRACT FROM AUTHOR]

Prophage enriched the prokaryotic genome, and their transcriptional factors improved the protein expression network of the host. In this study, we uncovered a new prophage-prophage interaction in E. coli JM83. The Rac prophage protein RacR (GenBank accession no. AVI55875.1) directly activated the transcription of φ80dlacZΔM15 prophage lysozyme encoding gene 19 (GenBank accession no. ACB02445.1, renamed it lysN, lysozyme nineteen), resulting in the growth defect of JM83. This phenomenon also occurred in DH5α, but not in BL21(DE3) and MG1655 due to the genotype differences. However, deletion of lysN could not completely rescued JM83 from the growth arrest, indicating that RacR may regulate other related targets. In addition, passivation of RacR regulation was found in the late period of growth of JM83, and it was transmissible to daughter cells. Altogether, our study revealed part of RacR regulatory network, which suggested some advanced genetic strategies in bacteria. [ABSTRACT FROM AUTHOR]

Background: As an important component of the causative agent of respiratory tract infections, enteric and eye infections, Human mastadenoviruses (HAdVs) species B spread easily in the crowd. In this study, we developed a recombinase polymerase amplification (RPA) assay for rapidly detecting HAdVs species B which was comprised of two different formats (real-time and lateral-flow device). Results: This assay was confirmed to be able to detect 5 different HAdVs species B subtypes (HAdV-B3, HAdV-B7, HAdV-B11, HAdV-B14 and HAdV-B55) without cross-reactions with other subtypes and other respiratory tract pathogens. This RPA assay has not only highly sensitivity with low detection limit of 50 copies per reaction but also short reaction time (< 15 min per detection). Furthermore, the real-time RPA assay has excellent correlation with real-time PCR assay for detection of HAdVs species B presented in clinical samples. Conclusions: Thus, the RPA assay developed in this study provides an effective and portable approach for the rapid detection of HAdVs species B. [ABSTRACT FROM AUTHOR]

Background: Botryococcus braunii is known for its high hydrocarbon content, thus making it a strong candidate feedstock for biofuel production. Previous study has revealed that a high cobalt concentration can promote hydrocarbon synthesis and it has little effect on growth of B. braunii cells. However, mechanisms beyond the cobalt enrichment remain unknown. This study seeks to explore the physiological and transcriptional response and the metabolic pathways involved in cobalt-induced hydrocarbon synthesis in algae cells. Results: Growth curves were similar at either normal or high cobalt concentration (4.5 mg/L), suggesting the absence of obvious deleterious effects on growth introduced by cobalt. Photosynthesis indicators (decline in Fv/Fm ratio and chlorophyll content) and reactive oxygen species parameters revealed an increase in physiological stress in the high cobalt concentration. Moreover, cobalt enrichment treatment resulted in higher crude hydrocarbon content (51.3% on day 8) compared with the control (43.4% on day 8) throughout the experiment (with 18.2% improvement finally). Through the de novo assembly and functional annotation of the B. braunii race A SAG 807-1 transcriptome, we retrieved 196,276 non-redundant unigenes with an average length of 1086 bp. Of the assembled unigenes, 89,654 (45.7%), 42,209 (21.5%), and 32,318 (16.5%) were found to be associated with at least one KOG, GO, or KEGG ortholog function. In the early treatment (day 2), the most strongly upregulated genes were those involved in the fatty acid biosynthesis and metabolism and oxidative phosphorylation, whereas the most downregulated genes were those involved in carbohydrate metabolism and photosynthesis. Genes that produce terpenoid liquid hydrocarbons were also well identified and annotated, and 21 (or 29.2%) were differentially expressed along the cobalt treatment. Conclusions: Botryococcus braunii SAG 807-1 can tolerate high cobalt concentration and benefit from hydrocarbon accumulation. The time-course expression profiles for fatty acid biosynthesis, metabolism, and TAG assembly were obtained through different approaches but had equally satisfactory results with the redirection of free long-chain fatty acid and VLCFA away from TAG assembly and oxidation. These molecules served as precursors and backbone supply for the fatty acid-derived hydrocarbon accumulation. These findings provide a foundation for exploiting the regulation mechanisms in B. braunii race A for improved photosynthetic production of hydrocarbons. [ABSTRACT FROM AUTHOR]

Background: Cryptosporidium spp. are important diarrhea-causing pathogens in humans and animals. Comparative genomic analysis indicated that Cryptosporidium-specific MEDLE family proteins may contribute to host adaptation of Cryptosporidium spp., and a recent study of one member of this family, CpMEDLE-2 encoded by cgd5_4590, has provided evidence supporting this hypothesis. In this study, another member of the protein family, CpMEDLE-1 of Cryptosporidium parvum encoded by cgd5_4580, which is distinct from CpMEDLE-2 and has no signature motif MEDLE, was cloned, expressed and characterized to understand its function. Methods: CpMEDLE-1 was expressed in Escherichia coli and polyclonal antibodies against the recombinant CpMEDLE-1 protein were prepared in rabbits. Quantitative PCR was used to analyze the expression profile of cgd5_4580 in C. parvum culture. Immunofluorescence staining was used to locate CpMEDLE-1 expression in life-cycle stages, and in vitro neutralization assay with antibodies was adopted to assess the role of the protein in C. parvum invasion. Results: The results indicated that cgd5_4580 had a peak expression at 2 h of C. parvum culture. CpMEDLE-1 was located in the mid-anterior region of sporozoites, probably within the dense granules. The neutralization efficiency of anti-CpMEDLE-1 antibodies was approximately 40%. Conclusions: The differences in protein and gene expression profiles between CpMEDLE-1 and CpMEDLE-2 suggest that MEDLE proteins have different subcellular locations, are developmentally regulated, could be potentially involved in the transcriptional regulation of the expression of parasite or host proteins and may exert their functions in different stages of the invasion and development process. [ABSTRACT FROM AUTHOR]

In Table 1, 'SO' and 'NO' should be corrected to ' $$ \mathrm{S}{\mathrm{O}}_4^{2-} $$ ' and ' $$ \mathrm{N}{\mathrm{O}}_3^{-} $$ ', respectively. The original article was corrected. [ABSTRACT FROM AUTHOR]

Background: Antibiotics biosynthesis is usually regulated by the cluster-situated regulatory gene(s) (CSRG(s)), which directly regulate the genes within the corresponding biosynthetic gene cluster (BGC). Previously, we have demonstrated that LmbU functions as a cluster-situated regulator (CSR) of lincomycin. And it has been found that LmbU regulates twenty non-lmb genes through comparative transcriptomic analysis. However, the regulatory mode of CSRs' targets outside the BGC remains unknown. Results: We screened the targets of LmbU in the whole genome of Streptomyces lincolnensis and found fourteen candidate targets, among which, eight targets can bind to LmbU by electrophoretic mobility shift assays (EMSA). Reporter assays in vivo revealed that LmbU repressed the transcription of SLINC_0469 and SLINC_1037 while activating the transcription of SLINC_8097. In addition, disruptions of SLINC_0469, SLINC_1037, and SLINC_8097 promoted the production of lincomycin, and qRT-PCR showed that SLINC_0469, SLINC_1037, and SLINC_8097 inhibited transcription of the lmb genes, indicating that all the three regulators can negatively regulate lincomycin biosynthesis. Conclusions: LmbU can directly regulate genes outside the lmb cluster, and these genes can affect both lincomycin biosynthesis and the transcription of lmb genes. Our results first erected the cascade regulatory circuit of LmbU and regulators outside lmb cluster, which provides the theoretical basis for the functional research of LmbU family proteins. [ABSTRACT FROM AUTHOR]

The Actinomycetes Streptomyces lincolnensis is the producer of lincosamide-type antibiotic lincomycin, a widely utilized drug against Gram-positive bacteria and protozoans. In this work, through gene knockout, complementation, and overexpression experiments, we identified LcbR1 (SLINC_1595), a GntR family transcriptional regulator, as a repressor for lincomycin biosynthesis. Deletion of lcbR1 boosted lincomycin production by 3.8-fold, without obvious change in morphological development or cellular growth. The homologues of LcbR1 are widely distributed in Streptomyces. Heterologous expression of SCO1410 from Streptomyces coelicolor resulted in the reduction of lincomycin yield, implying that the function of LcbR1 is conserved across different species. Alignment among sequences upstream of lcbR1 and their homologues revealed a conserved 16-bp palindrome (-TTGAACGATCCTTCAA-), which was further proven to be the recognition motif of LcbR1 by electrophoretic mobility shift assays (EMSAs). Via this motif, LcbR1 suppressed the transcription of lcbR1 and SLINC_1596 sharing the same bi-directional promoter. SLINC_1596, one important target of LcbR1, exerted a positive effect on lincomycin production. As detected by quantitative real-time PCR (qRT-PCR) analyses, the expressions of all selected structural (lmbA, lmbC, lmbJ, lmbV, and lmbW), resistance (lmrA and lmrB) and regulatory genes (lmrC and lmbU) from lincomycin biosynthesis cluster were upregulated in deletion strain ΔlcbR1 at 48 h of fermentation, while the mRNA amounts of bldD, glnR, ramR, SLCG_Lrp, and SLCG_2919, previously characterized as the regulators on lincomycin production, were decreased in strain ΔlcbR1, although the regulatory effects of LcbR1 on the above differential expression genes seemed to be indirect. Besides, indicated by EMSAs, the expression of lcbR1 might be regulated by GlnR, SLCG_Lrp, and SLCG_2919, which shows the complexity of the regulatory network on lincomycin biosynthesis. Key points: • LcbR1 is a novel and conservative GntR family regulator regulating lincomycin production. • LcbR1 modulates the expressions of lcbR1 and SLINC_1596 through a palindromic motif. • GlnR, SLCG_Lrp, and SLCG_2919 can control the expression of lcbR1. [ABSTRACT FROM AUTHOR]

Abstract Metabolic division of labor is a key ecological strategy in bacteria to allow concurrent execution of multiple tasks through functional differentiation and metabolite exchange. While it is prevalent in nature, a lot of novel interactions remain to be further explored for improved wastewater biological treatment. Here, we present a combined experimental and modeling study on the simultaneous removal of nitrogen and thiocyanate from wastewater by using a syntrophic microbial community. The syntrophic division of labor was achieved by coupling autotrophic denitrification (AD) and anaerobic ammonium oxidation (AN) through both cooperative and competitive interactions. We demonstrated that the syntrophic community can achieve almost complete removal of all pollutants under certain initial conditions. We then perturbed the initial condition by varying the concentration ratio between ammonium to thiocyanate as well as the biomass ratio between AD and AN. Our observations show that adding ammonium negatively impacts the thiocyanate removal efficiency and adding anammox bacteria have opposite effects on the removal efficiency of thiocyanate and ammonium. Using a mathematical model, we simultaneously varied these two initial conditions and identified the parameter regime where our syntrophic ecosystem can be most efficient in removing total nitrogen. By highlighting the utility of syntrophic pair of functional bacteria in removing pollutants, our study will facilitate the rational design of more complex microbial consortia for the removal of toxic and hazardous compounds from industrial wastewater. Graphical abstract Image 1 Highlights • Syntrophic microbial community was developed for thiocyanate wastewater treatment. • The microbial community involved autotrophic denitrifying and anammox bacteria. • Removal of pollutants were promoted by cooperative behavior but not competitive. • A mathematical model was developed and used it to predict removal of pollutants. [ABSTRACT FROM AUTHOR]

Lincomycin is a broad-spectrum antibiotic and particularly effective against Gram-positive pathogens. Albeit familiar with the biosynthetic mechanism of lincomycin, we know less about its regulation, limiting the rational design for strain improvement. We therefore analyzed two-component systems (TCSs) in Streptomyces lincolnensis, and selected eight TCS gene(s) to construct their deletion mutants utilizing CRISPR/Cas9 system. Among them, lincomycin yield increased in two strains (Δ3900–3901 and Δ5290–5291) while decreased in other four strains (Δ3415–3416, Δ4153–4154, Δ4985, and Δ7949). Considering the conspicuous effect, SLINC_5291-5290 (AflQ1-Q2) was subsequently studied in detail. Its repression on lincomycin biosynthesis was further proved by gene complementation and overexpression. By binding to a 16-bp palindromic motif, the response regulator AflQ1 inhibits the transcription of its encoding gene and the expression of eight operons inside the lincomycin synthetic cluster (headed by lmbA, lmbJ, lmbK, lmbV, lmbW, lmbU, lmrA, and lmrC), as demonstrated by quantitative RT-PCR and electrophoretic mobility shift assays. Besides, the regulatory genes including bldD, glnR, lcbR1, and ramR are also regulated by the TCS. According to the screening towards nitrogen sources, aspartate affects the regulatory behavior of histidine kinase AflQ2. And in return, AflQ1 accelerates aspartate metabolism via ask-asd, asd2, and thrA. In summary, we acquired six novel regulators related to lincomycin biosynthesis, and elucidated the regulatory mechanism of AflQ1-Q2. This highly conserved TCS is a promising target for the construction of antibiotic high-yield strains. Key points: • AflQ1-Q2 is a repressor for lincomycin production. • AflQ1 modulates the expression of lincomycin biosynthetic and regulatory genes. • Aspartate affects the behavior of AflQ2, and its metabolism is promoted by AflQ1. [ABSTRACT FROM AUTHOR]

An unusual decrease of methylene blue’s equilibrium adsorption density ( q e ) with the increasing initial concentration ( C 0 ) was observed in previous studies. Further studies are required to understand the mechanism related to this phenomenon. For exploring the effect of molecular structure on cationic dye’s adsorption, the adsorption behavior of methylene blue (MB) and crystal violet (CV) onto natural vermiculite were investigated. As a comparative dye, CV has the same ionic charge (+1) with MB, but its triangular molecular structure is significantly different with MB’s linear molecular structure. The isotherm results indicated that the MB’s q e at 25 °C decreased from 0.076 to 0.053 mmol g −1 with the C 0 increased from 0.3 to 0.5 mmol L −1 . The Langmuir model was not able to describe its isotherm curves. On the contrary, CV showed a typical Langmuir isotherm with a R 2 of 0.99 at 25 °C. Furthermore, the difference between MB and CV’s adsorption behavior was also reflected in the column experiment. The breakthrough time of MB exhibited a 71% decrease with the influent concentration increasing from 0.25 to 0.50 mmol L −1 , whereas CV only behaved a 45% decrease. Results of this study demonstrate that the molecular structure could be responsible for the unusual decline of MB’s adsorption isotherm under high initial concentrations. Due to the linear structure, the molecules of MB could cause the ‘adsorbate–adsorbate’ steric effect more easily compared to CV, leading a decline of the equilibrium adsorption density. Therefore, the initial concentration of MB should be controlled accordingly to achieve the optimal adsorption performance of natural clays such as vermiculite. [ABSTRACT FROM AUTHOR]

The development of aquaculture has been hampered by different aquatic pathogens that can cause edwardsiellosis, vibriosis, or other diseases. Therefore, developing a broad spectrum vaccine against different fish diseases is necessary. In this study, fructose 1,6-bisphosphate aldolase (FBA), a conserved enzyme in the glycolytic pathway, was demonstrated to be located in the non-cytoplasmic components of five aquatic pathogenic bacteria and exhibited remarkable protection and cross-protection against these pathogens in turbot and zebrafish. Further analysis revealed that sera sampled from vaccinated turbot had a high level of specific antibody and bactericidal activity against these pathogens. Meanwhile, the increased expressions of immune response-related genes associated with antigen recognition and presentation indicated that the adaptive immune response was effectively aroused. Taken together, our results suggest that FBA can be utilized as a broad-spectrum vaccine against various pathogenic bacteria of aquaculture in the future. [ABSTRACT FROM AUTHOR]

As a typical industrial wastewater, coking wastewater is characterized as high organic load, complicated composition and strong biological inhibition. Based on the analysis between organic composition and toxicity contribution of coking wastewater, a selective removal for targeting hydrophobic contaminants was conducted by organic modified acid-vermiculites (Chlorotrimethylsilane modification, CTMS-V; and Chlorotriethysilane modification, CTES-V), powdered activated carbon (PAC) and XAD-16 polymer adsorbent. Binary solution containing hydrophilic (phenol) and hydrophobic (diethyl phthalate, DEP) compounds was employed to evaluate the performance of selective adsorption then coking wastewater was further tested. Results of binary adsorption indicated that the average adsorption percentages of DEP for PAC, XAD-16, CTMS-V and CTES-V were 32.6 ± 11.1%, 50.8 ± 17.4%, 68.7 ± 22.6%, 75.5 ± 27.4% (mean ± standard deviation, n = 5) at varying phenol:DEP ratios (10–100, mol:mol). Coking wastewater treated by PAC, XAD-16 CTMS-V and CTES-V had a decrease of chemical oxygen demand (COD) at 24.6 ± 3.0%, 11.3 ± 1.5%, 4.4 ± 0.08% and 6.8 ± 1.1%. For biochemical oxygen demand (BOD 5 ), PAC and XAD-16 gave a decrease of 47.5 ± 5.6% and 7.8 ± 1.4%, whereas CTMS-V and CTES-V gave an increase of 36.7 ± 4.1% and 57.2 ± 4.6%, respectively. The resulting BOD 5 :COD were 0.21 ± 0.03, 0.31 ± 0.04, 0.42 ± 0.05 and 0.50 ± 0.05 after treatment by PAC, XAD-16, CTMS-V and CTES-V, respectively. Post incubation of treated coking wastewater showed that the residual TOC after ten-day incubation were 73.1 ± 1.5%, 77.9 ± 3.5%, 73.2 ± 3.7% and 59.2 ± 3.0% for PAC, XAD-16 CTMS-V and CTES-V, respectively. The non-π functional surface (i.e., –CH 3 and –CH 2 CH 3 ) of modified acid-vermiculites played a critical role for capturing hydrophobic compounds from the solution with high concentration of hydrophilic competitive compounds. [ABSTRACT FROM AUTHOR]

Edwardsiella tarda , an enteric opportunistic pathogen, is associated with acute to chronic edwardsiellosis in cultured fish, resulting in heavy losses in aquaculture. To date, the pathogenesis of E. tarda has been extensively studied and a great deal of vaccine candidates have been attempted. However, the research on the predisposition of E. tarda infection is poorly reported. In this study, the effects of intestinal inflammation on E. tarda infection were investigated using a zebrafish model that influenced by perturbation of intestinal microbiota. Featured symptoms of edwardsiellosis were observed in intestinal inflammatory zebrafish compared with healthy fish. Higher bacterial numbers were detected in both mucosal tissues (intestine, skin and gills) and lymphoid tissues (liver, spleen and kidney) of inflammatory zebrafish while the bacterial loads in healthy zebrafish appeared to be relatively lower by 10–100 folds. Moreover, significant up-regulation of IL-1β, TNF-α and iNOS was noticed in multiple tissues of zebrafish with intestinal inflammation between 6 and 72 h post infection. However, only moderate elevation was observed in the gills and liver of healthy fish. Furthermore, the expression of genes involved in neutrophil recruitment (mpx, IL-8 and LECT2) and antimicrobial response (β-defensin and hepcidin) showed notable up-regulation in the intestine of inflammatory zebrafish. These results demonstrate that fish with intestinal inflammation is more susceptible to E. tarda and the antimicrobial response during E. tarda infection might inhibit the growth of intestinal microbiota. Our results suggest that maintaining good management to avoid intestinal inflammation is a feasible prevention measure against edwardsiellosis. [ABSTRACT FROM AUTHOR]

The hydrolytic acidification process has a strong ability to conduct denitrogenation and increase the biological oxygen demand/chemical oxygen demand ratio in O/H/O coking wastewater treatment system. More than 80% of the total nitrogen (TN) was removed in the hydrolytic bioreactor, and the hydrolytic acidification process contributed to the provision of carbon sources for the subsequent nitrification process. The structure and diversity of microbial communities were elaborated using high-throughput MiSeq of the 16S rRNA genes. The results revealed that the operational taxonomic units (OTUs) belonged to phyla Bacteroidetes, Betaproteobacteria, and Alphaproteobacteria were the dominant taxa involved in the denitrogenation and degradation of refractory contaminants in the hydrolytic bioreactor, with relative abundances of 22.94 ± 3.72, 29.77 ± 2.47, and 18.23 ± 0.26%, respectively. The results of a redundancy analysis showed that the OTUs belonged to the genera Thiobacillus, Rhodoplanes, and Hylemonella in the hydrolytic bioreactor strongly positively correlated with the chemical oxygen demand, TN, and the removal of phenolics, respectively. The results of a microbial co-occurrence network analysis showed that the OTUs belonged to the phylum Bacteroidetes and the genus Rhodoplanes had a significant impact on the efficiency of removal of contaminants that contained nitrogen in the hydrolytic bioreactor. The potential function profiling results indicate the complementarity of nitrogen metabolism, methane metabolism, and sulfur metabolism sub-pathways that were considered to play a significant role in the process of denitrification. These results provide new insights into the further optimization of the performance of the hydrolytic bioreactor in coking wastewater treatment. [ABSTRACT FROM AUTHOR]

In recent years, increasing diseases especially bacterial diseases have brought a host of losses with the expansive cultivation of turbot ( Scophthalmus maximus ). In order to do more research about the immune system of turbot for better understanding the mechanism of resisting diseases, the immunoglobulin genes related to secretory and membrane-bound IgM (s-IgM and m-IgM) of turbot were cloned using homology sequences cloning and SMART RACE PCR method. The heavy chain of s-IgM cDNA is 1900 bp in length including a leader region, a variable region, four constant regions (CH1, CH2, CH3 and CH4) and a C-terminal while the cDNA of m-IgM is 1795 bp with the same leader region, variable region, three constant regions (CH1, CH2 and CH3) and two transmembrane regions (TM1 and TM2). The sequence of IgM gene was also obtained and the structure consisted of V–CH1–CH2–CH3–CH4-TM1-TM2 is similar to other fishes. The highest level of s-IgM expression was observed in spleen, followed by kidney, gills, eyes, skin of the healthy turbot whereas the same profile of m-IgM expression is found with low level. And s-IgM takes up dominant proportion of total IgM expression. Also the relative expressions of s-IgM and m-IgM were analyzed in turbot vaccinated with the live attenuated vaccine Vibrio anguillarum . Not only the transcriptions of both s-IgM and m-IgM in liver, spleen and kidney of turbot injected with V. anguillarum MVAV6203 were up-regulated but also the expressions of s-IgM and m-IgM in spleen, kidney, gut, skin and gills of bath-vaccinated turbot were increased. Comparing the ratio changes of relative expression of m-IgM and s-IgM in vaccinated turbot, we found that the proportion of m-IgM were increasing in both administration routes, which probably indicated that the increasing expression of m-IgM strengthen the phagocytic ability of B cells. [ABSTRACT FROM AUTHOR]

Background: A candidate vaccine, live attenuated Vibrio anguillarum developed in our laboratory could prevent vibriosis of fish resulted from V. anguillarum and V. alginolyticus. To elucidate the molecular mechanisms underlying the vaccine protection, we used microarray technology to compare the spleen transcriptomes of bath-vaccinated and unvaccinated zebrafish at 28 days post vaccination. Principal Findings: A total of 2164 genes and transcripts were differentially expressed, accounting for 4.9% of all genes represented on the chip. In addition to iron metabolism related to the innate immunity and the signaling pathways, these differentially expressed genes also involved in the adaptive immunity, mainly including the genes associated with B and T cells activation, proliferation and expansion. Transcription profiles of Th17-related transcription factors, cytokines and cytokine receptors during 35 days post-vaccination implied that Th17 cells be activated in bath-vaccinated zebrafish. Conclusion/Significance: The transcriptome profiling with microarray revealed the Th17-like immune response to bath-vaccination with the live attenuated V. anguillarum in zebrafish. [ABSTRACT FROM AUTHOR]

Abstract: Ferritin, an iron-binding protein, plays a role in host immune response to invading stimulus. Two ferritin subunit cDNAs, lycfh and lycfm, were identified from large yellow croaker, Pseudosciaena crocea. Analysis of the lycfh and lycfm 5′-UTR showed that both had a putative iron responsive element (IRE). Amino acid sequence alignment and phylogenetic analysis indicated that LycfH and LycfM had high identity to H and M type subunit of vertebrate ferritins respectively, while both of them showed the low identity to L type subunit. In all eight tissues examined, lycfh and lycfm expressions were detectable on transcriptional level. Real-time PCR assay indicated that the transcriptional levels of lycfh and lycfm were significantly increased in liver, spleen and kidney of the fish stimulated by attenuated live Vibrio anguillarum strain. Furthermore, ferritin subunit H and M were probably two candidates of immune molecules involved in acute phase response in large yellow croaker because their transcriptional levels were quickly increased and reached the peak levels at 12 h in liver after challenged with bacteria. [Copyright &y& Elsevier]

Microalgae are known to be abundant in various habitats around the globe, and are rich in high value-added products such as fatty acids, polysaccharides, proteins, and pigments. Microalgae can be exploited as the basic and primitive food source of aquatic animals. We investigated the effects of dietary supplementation with Schizochytrium sp., Spirulina platensis, Chloroella sorokiniana, Chromochloris zofingiensis, and Dunaliella salina on the growth performance, immune status, and intestinal health of zebrafish (Danio rerio). The results showed that these five microalgae diets could improve the feed conversion rate (FCR), especially the D. salina (FCR = 1.02%) and Schizochytrium sp. (FCR = 1.20%) additive groups. Moreover, the microalgae diets decreased the gene expression level of the pro-inflammatory cytokines IL6, IL8, and IL1β at a normal physiological state of the intestine, especially the Schizochytrium sp., S. platensis, and D. salina dietary groups. The expression of neutrophil marker b7r was increased in the C. sorokiniana diet group; after, the zebrafish were challenged with Vibrio anguillarum, improving the ability to resist this disease. We also found that microalgae diets could regulate the gut microbiota of fish as well as increase the relative abundance of probiotics. To further explain, Cetobacterium was significantly enriched in the S. platensis additive group and Stenotrophomonas was higher in the Schizochytrium sp. additive group than in the other groups. Conversely, harmful bacteria Mycoplasma reduced in all tested microalgae diet groups. Our study indicated that these microalgae could serve as a food source supplement and benefit the health of fish. Key points: • Microalgae diets enhanced the growth performance of zebrafish. • Microalgae diets attenuated the intestinal inflammatory responses of zebrafish. • Microalgae diets modulated the gut microbiota composition to improve fish health. [ABSTRACT FROM AUTHOR]

Due to the intervention of human activities, the background values of riverbed sediment exhibit spatiotemporal variability, which can affect the accuracy of risk assessment results. Using risk assessment that do not rely on background values is an executable alternative to avoid such problems. In this study, a relative pollution level assessment (RPLA) method which was based on the statistical results of relevant literatures was proposed. This method includes a four-step data processing procedure to extract the evaluation indexes of relative pollution degree of pollutants in environment and a series of relative pollution status assessment methods to evaluate the overall relative pollution level and regional difference of world-wide rivers. To demonstrate how to use RPLA method, 310 relevant literatures covering world-wide rivers were selected. And the ambient background value ( x ̅), the world-wide threshold values (WWTV) and the relative pollution grades (LEVEL I ∼ IV) of 9 target metals (Cr, Ni, Cu, Zn, As, Cd, Pb, Sb and Tl) in riverbed surface sediments of world-wide rivers were extracted and used for evaluation. Moreover, the stability and applicability of RPLA method were evaluated. Results show that the evaluation results of RPLA method are robust and comparable with traditional evaluation method. [Display omitted] • A methodology for evaluating relative pollution levels has been proposed. • Evaluation indexes of relative pollution degree of pollutants were extracted. • These indexes are extracted from the statistical results of relevant literatures. • Study proves that evaluation results of this evaluation method are robust. • The evaluation method in this study can serve as an alternative to the tradition. [ABSTRACT FROM AUTHOR]

Eukaryotic microalgae are important primary producers in nature that play an important role in the energy cycle of nature. The eukaryotic microalgae are also regarded as potential bioactive substance producers. In recent years, with the aid of genetic engineering, eukaryotic microalgae have found a wider range of potential applications in medicine, food, health products, cosmetics, and environmental protection. This article reviews the state of the art of microalga genetic engineering from the aspects of gene transfer system, gene editing technology, and screening method, with examples of the enhancement of lipids, carotenoids, polysaccharide, and functional proteins. Potential application scenarios of microalga genetic engineering and their products in the field of food and medicine are also highlighted. Furthermore, strategies for protein expression optimization in eukaryotic microalgae are reviewed. The existing shortcomings of eukaryotic microalga genetic engineering are also analyzed and highlighted. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel biofilm carrier with quorum sensing regulatory ability was constructed. • The novel carrier prompts granular sludge-like biofilm formation. • The novel carrier enriched anammox bacteria (AnAOB) at 3.2 times the original speed. • A new ability of cyclodextrin to enrich difficult-to-culture bacteria was discovered. • Exogenous quorum sensing signaling molecules can reconstruct AnAOB dominant species. High-efficiency enrichment of functional bacteria is one of the biggest technical barriers to the application of anaerobic ammonium oxidation (anammox). This study combined biofilm carriers and quorum sensing to achieve rapid biomass accumulation. A biofilm carrier with biomass adsorption and quorum sensing regulation functions was developed for the rapid start-up of the reactor and enrichment of anammox bacteria (AnAOB). The nitrogen removal rates of the three reactors were further tested, and the carrier mechanism was explored. The start-up time of the reactor with the modified carriers was 28 days, which was ∼44 % shorter than that of the reactor without carriers. After 90 days of operation, the absolute abundance of total AnAOB was 3.2 times that in the control group. The modified carrier promoted the rapid adhesion of biomass through the hydrophobic cavity of cyclodextrin and induced rapid proliferation, enhancement of activity, and extracellular protein secretion of AnAOB through quorum sensing signaling molecules. Finally, a special hydrophobic biofilm with granular sludge characteristics was formed on the modified carrier through the self-assembly of hydrophobic biomass particles. Overall, we propose a novel approach to enrich anammox bacteria involving a combination of quorum sensing and biofilm carriers. [ABSTRACT FROM AUTHOR]

Abstract This study proposes a new evaluation method based on expert scoring and data normalization to optimize operational conditions of sludge pyrolysis and assess the comprehensive benefits of the adsorption process in coking wastewater treatment. Pyrolysis temperature, holding time and heating rate were considered as the experimental parameters in sludge pyrolysis. They were optimized by the proposed method, considering raw material cost, net energy consumption, carbon emission and adsorption capacity of sludge-derived bio-char (SB). Two operational modes (cyclic centralized and traditional distributed) were compared to identify a better solution for coking wastewater treatment. The results showed that the optimized operational conditions of coking sludge pyrolysis were that temperature of 550 °C, holding time of 60 min and heating rate of 20 °C/min, using the proposed method. Cyclic centralized mode has been demonstrated as the better mode for wastewater treatment by the proposed method, due to the higher comprehensive score of −0.296. It is a promising technology for sustainable wastewater treatment in terms of sludge recycling, energy saving and carbon emission reduction. Highlights • Sludge-derived bio-char was prepared by pyrolysis and reused in wastewater adsorption. • A new comprehensive evaluation method of sludge pyrolysis has been proposed. • Pyrolysis conditions of temperature, holding time and heating rate were optimized. • Net energy consumption and carbon emission were proved as the main evaluation indexes. • Cyclic centralized mode was superior to traditional distribute in adsorption process. [ABSTRACT FROM AUTHOR]

Abstract Functional identification and elimination of activity-decayed sludge are helpful for improving the performance of biological treatment process. However, cell decay-associated changes in biological functions have not been explored for gravity-separated sludge. In this work, sludge flocs from the aerobic basin of a wastewater treatment plant treating high-concentration organic coking wastewater was fractionated according to settling velocity, i.e. sludge F (fast settling), sludge M (moderate settling) and sludge S (slow settling). Sludge volume index (SVI), mean floc size, dehydrogenase activity, specific oxygen uptake rate (SOUR), extracellular polymeric substances (EPS) content and aggregation interaction were investigated in the fractionated sludges. Apoptosis-like decayed cell distribution (ALDCD), a novel property of sludge, was proposed to describe sludge decay based on cell membrane variation. ALDCD of sludge F was 6.64% and 13.5% lower than sludge M and S, respectively. Microbial community and functional prediction revealed that sludge F exhibited the highest microbial potential for organic removal and sludge M had the highest potential for nitrogen metabolism while sludge S had the lowest potential for both. Our analysis suggests that the treatment efficiency might be enhanced by retaining compact sludge flocs while eliminating dispersive sludge flocs. This study also facilitates the identification and elimination of functional microbial groups from decayed sludge in wastewater treatment. Graphical abstract Image 1 Highlights • Aerobic floccular sludge was gravity-separated into different fractions. • The light fraction showed the highest SVI and the lowest aggregation ability. • Apoptosis-like decayed cell distribution was proposed to evaluate sludge decay. • The apoptosis-like decay was associated with variations in microbial functions. • Slow-settling flocs have the lowest potential in COD and nitrogen removal. [ABSTRACT FROM AUTHOR]