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The construction of lithium–sulfur battery cathode materials while simultaneously achieving high areal sulfur‐loading, adequate sulfur utilization, efficient polysulfides inhibition, rapid ion diffusion, etc. remains a major challenge. Herein, an internal regulatory strategy to fabricate the unique walnut‐like yolk–shell carbon flower@carbon nanospheres is presented (WSYCS) as sulfur hosts. The internal carbon flower, suitable cavity, and external carbon layer effectively disperse the insulate sulfur, accommodate volumetric expansion, and confine polysulfides, thus improving the performance of lithium–sulfur batteries. The finite element simulation method also deduces the enhanced Li+ diffusion and lithium–sulfur reaction kinetics. More importantly, WSYCS2 is grafted onto carbon fiber (CF) by electro‐spinning method to form a tandem WSYCS2@CF 3D film as a sulfur host for the free‐standing electrode. The corresponding battery exhibits an extremely high areal capacity of 15.5 mAh cm−2 with a sulfur loading of 13.4 mg cm−2. Particularly, the flexible lithium–sulfur pouch cell delivers a high capacity of 8.1 mAh cm−2 and excellent capacity retention of 65% over 800 cycles at a relatively high rate of 1C, corresponding to a calculated energy density of 539 Wh kg−1 and 591 Wh L−1. This work not only provides guidance for tailoring thick carbon/sulfur electrodes but also boosts the development of practical lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

This current work investigated the effects of increasing temperature on microbial biofilm composition during the conversion of the lignocellulosic agricultural wastes into biohydrogen using a dark-fermentation and Microbial electrolysis cell integrated system bio-catalyzed by a mixed culture. The reactors were operated under a thermophilic environment (R-Th) and directly compared with the reactors operated under mesophilic conditions (R-Me). The R-Th anodic biofilm composition was dominated by thermophilic lignocellulose-degrading and hydrogen-producing microorganisms belonging to the phyla of Proteobacteria (37.82 %), Thermotogota (35.94 %), and Coprothermobacteria (8.3 %) whereas the same phyla were noticeably less represented under mesophilic conditions. Compared to R-Th, R-Me anodic biofilm was characterized by more diverse microbial communities, and concomitantly promoted the proliferation of the methanogenic archaeal genera including Methanosarcina sp. (71.87 %), Methanothermobacter sp. (17.23 %), Methanomethylovorans sp. (8.35 %) , Methanobrevibacter sp. (0.97 %), Methanobacterium sp. (0.79 %), Methanosphaera sp. (0.28 %), and Methanosaeta sp. (0.28 %). These results clearly show that the agricultural waste-fed DF-MEC integrated reactors performed under a thermophilic environment significantly promoted thermophilic-hydrogen producing microbial communities and inhibited the hydrogen-consuming microbial growth, which thus enhanced hydrogen yield. This work will significantly help the practitioners in selecting the suitable operating temperature during the fermentative conversion of agricultural wastes into biohydrogen energy on a large scale. [Display omitted] • DF-MEC integrated system was used to bioconvert lignocellulosic agricultural wastes into biohydrogen by a mixed culture. • R-Th anodic biofilm composition was dominated by Proteobacteria (37.82 %), Thermotogota (35.94 %), and Coprothermobacteria (8.3 %). • Bioreactors operated under thermophilic conditions promoted thermophilic hydrogen-producing microbial growth. • R-Me protocol enriched more diverse microbial communities and promoted the proliferation of the methanogenic archaeal genera. [ABSTRACT FROM AUTHOR]

In this current research, the left-over residues collected from the dark fermentation-microbial electrolysis cells (DF-MEC) integrated system solely biocatalyzed by activated sludge during the bioconversion of the agricultural straw wastes into hydrogen energy, was investigated for its feasibility to be used as a potential alternative biofertilizer to the commonly costly inorganic ones. The results revealed that the electrohydrogenesis left-over residues enriched various plant growth-promoting microbial communities including Enterobacter (8.57%), Paenibacillus (1.18%), Mycobacterium (0.77%), Pseudomonas (0.65%), Bradyrhizobium (0.12%), Azospirillum (0.11%), and Mesorhizobium (0.1%) that are generally known for their ability to produce different essential phytohormones such as indole-3-acetic acid/indole acetic acid (IAA) and Gibberellins for plant growth. Moreover, they also contain both phosphate-solubilizing and nitrogen-fixing microbial communities that remarkably provide an adequate amount of assimilable phosphorus and nitrogen required for enhanced plants or crop growth. Furthermore, macro-, and micronutrients (including N, P, K, etc.) were all analyzed from the residues and detected adequate appreciate concentrations required for plant growth promotions. The direct application of MEC-effluent as fertilizer in this current study conspicuously promoted plant growth (Solanum lycopersicum L. (tomato), Capsicum annuum L. (chilli), and Solanum melongena L. (brinjal)) and speeded up flowering and fruit-generating processes. Based on these findings, electrohydrogenesis residues could undoubtedly be considered as a potential biofertilizer. Thus, this technology provides a new approach to agricultural residue control and concomitantly provides a sustainable, cheap, and eco-friendly biofertilizer that could replace the chemical costly fertilizers. [ABSTRACT FROM AUTHOR]

Summary: Gastrointestinal (GI) microbiota is one of the most complicated microbial ecosystems and is vital in regulating biological processes associated with nutrient absorption and homeostatic maintenance. Although several efforts have been achieved in characterizing bacterial communities across gut regions, the variation of non‐bacterial communities across GI tracts is still largely unexplored. To address this, we investigated microbial biogeography throughout the whole GI tracts of Ujimqin sheep (Ovis aries) by amplicon sequencing which targeted bacteria, fungi, and archaea. The results indicated that the community structures of all three domains were significantly distinguished according to GI tracts (stomach, small intestine, and large intestine), and a more strong and efficient species interaction was detected in small intestine based on cross‐domain network analysis. Moreover, a between‐domain difference in microbial assembly mechanism of among‐GI regions was revealed here, wherein bacterial community is dominantly governed by variable selection (explaining ~62% of taxa turnover), while fungal and archaeal communities mainly governed by homogenizing dispersal (explaining ~49% and 60% of the turnover, respectively). Overall, these data highlight the GI section‐ and domain‐dependence of GI microbial structure and assembly mechanism, suggesting that multi‐domain should be explicitly considered when evaluating the influences of GI selection on gut microbial communities. [ABSTRACT FROM AUTHOR]

Background: Biosurfactants, being highly biodegradable, ecofriendly and multifunctional compounds have wide applications in various industrial sectors including environmental bioremediation. Surfactin, a member of lipopeptide family, which is considered as one of the most powerful biosurfactants due to its excellent emulsifying activities as well as environmental and therapeutic applications. Therefore, the aim of this study was to investigate the newly isolated bacterial strain S2MT for production of surfactin-like biosurfactants and their potential applications for oil-contaminated soil remediation. Results: In this study, the strain S2MT was isolated from lake sediment and was identified as Bacillus nealsonii based on transmitted electron microscopy (TEM) and 16S rRNA ribo-typing. The strain S2MT produced biosurfactant that reduced the surface tension (34.15 ± 0.6 mN/m) and displayed excellent emulsifying potential for kerosene (55 ± 0.3%). Additionally, the maximum biosurfactant product yield of 1300 mg/L was achieved when the composition of the culture medium was optimized through response surface methodology (RSM). Results showed that 2% glycerol and 0.1% NH4NO3 were the best carbon/nitrogen substrates for biosurfactant production. The parameters such as temperature (30 °C), pH (8), agitation (100 rpm), NH4NO3 (0.1%) and NaCl (0.5%) displayed most significant contribution towards surface tension reduction that resulted in enhanced biosurfactant yield. Moreover, the extracted biosurfactants were found to be highly stable at environmental factors such as salinity, pH and temperature variations. The biosurfactants were characterized as cyclic lipopeptides relating to surfactin-like isoforms (C13–C15) using thin-layer chromatography (TLC), Ultra high performance liquid chromatography and mass spectrometry (UHPLC-MS). The crude biosurfactant product displayed up to 43.6 ± 0.08% and 46.7 ± 0.01% remediation of heavy engine-oil contaminated soil at 10 and 40 mg/L concentrations, respectively. Conclusion: Present study expands the paradigm of surfactin-like biosurfactants produced by novel isolate Bacillus nealsonii S2MT for achieving efficient and environmentally acceptable soil remediation as compared to synthetic surfactants. [ABSTRACT FROM AUTHOR]

Rational design of hollow micro‐ and/or nano‐structured cathodes as sulfur hosts has potential for high‐performance lithium‐sulfur batteries. However, their further commercial application is hindered because infusing sulfur into hollow hosts is hard to control and the interactions between high loading sulfur and electrolyte are poor. Herein, we designed hierarchical porous hollow carbon nanospheres with radially inwardly aligned supporting ribs to mitigate these problems. Such a structure could aid the sulfur infusion and maximize sulfur utilization owing to the well‐ordered pore channels. This highly organized internal carbon skeleton can also enhance the electronic conductivity. The hollow carbon nanospheres with further nitrogen‐doping as the sulfur host material exhibit good capacity and excellent cycling performance (0.044 % capacity degradation per each cycle for 1000 cycles). [ABSTRACT FROM AUTHOR]

Rational design of hollow micro‐ and/or nano‐structured cathodes as sulfur hosts has potential for high‐performance lithium‐sulfur batteries. However, their further commercial application is hindered because infusing sulfur into hollow hosts is hard to control and the interactions between high loading sulfur and electrolyte are poor. Herein, we designed hierarchical porous hollow carbon nanospheres with radially inwardly aligned supporting ribs to mitigate these problems. Such a structure could aid the sulfur infusion and maximize sulfur utilization owing to the well‐ordered pore channels. This highly organized internal carbon skeleton can also enhance the electronic conductivity. The hollow carbon nanospheres with further nitrogen‐doping as the sulfur host material exhibit good capacity and excellent cycling performance (0.044 % capacity degradation per each cycle for 1000 cycles). [ABSTRACT FROM AUTHOR]

[Display omitted] • This study reported an optimum applied voltage of 0.8 V for best MEC performance. • MEC0.8 achieved maximum H 2 production of 6.017 mmoles H 2 /g-COD with a high COD removal of ∼73.4 %. • Both anodic biofilm viability and microbial cell shape were largely damaged at high voltages. • Among others, MEC1.0 protocol was characterized by a high charge transfer resistance of 16.06 Ω. The microbial electrolysis cell (MEC) is a future clean technology with a wide range of applications in energy recycling fields, particularly for hydrogen production. Applied voltage governs the electrochemically active microbial activities in MEC and further affects hydrogen production. Therefore, this study investigated the impacts of the applied voltages on MEC performance and anodic biofilm viability during the biotransformation of straw waste biomass into green hydrogen energy in an anaerobic environment. The results revealed that the COD removal efficiency and bioH 2 yield increased with the augmentation of the applied voltage and beyond 0.8 V started decreasing. Among the performed protocols MEC0.8 depicted the best performance with a maximum H 2 production of 6.017 mmoles H 2 /g-COD which was ∼28.2 % and ∼9.8 % higher than that of MEC0.5 and MEC1.0 respectively. Moreover, it also achieved a maximum COD removal of 73.4% and a coulombic efficiency (CE) of 68.4%. Consistently, the anodic biofilm viability and bacterial cell shape in the MECs performed with 0.5 V and 0.8 V were less affected but largely damaged in a high potential operated protocol (MEC1.0), suggesting that the mixed electroactive consortia were so sensitive to high potentials. Furthermore, MEC1.0 displayed a high charge transfer resistance of 16.06 Ω which was ∼22.1 %, and ∼73.7 % higher than that of MEC0.8, and MEC0.5 respectively. Based on our novel study's results, the optimal applied voltage for the best performance of MEC was 0.8 V; and this information will be a pillar for future MEC operations prior to maintaining its industrial practice. [ABSTRACT FROM AUTHOR]

Despite that a variety of carbon materials have been explored for electrochemical energy storage, rationally design the carbon structure for efficient electrons transfer and ions diffusion to further improve its performance is still a challenge. In this report, a novel three-dimension hybrid carbon material (NCNF/RGO) prepared from reduced graphene oxide (RGO) and N-doped carbon nanoflower (NCNF) consisting of carbon nanosheets has been fabricated by a hydrothermal treatment and freeze-drying method, and demonstrated as supercapacitor's electrode. Benefiting from such structure design with thin porous nanosheets, interworking mesoporous channel and RGO wrapping for efficient electrolyte ions diffusion and electrons transfer, the resulting hybrid electrode displays high specific capacitance of 344 F g−1 at a current density of 0.5 A g−1 and 179 F g−1 even at 50 A g−1 in the KOH electrolyte, and 152 F g−1 at 1 A g−1 in the ionic liquid electrolyte with a wide voltage range. Significantly, the assembled symmetric supercapacitor using the NCNF/RGO as electrode materials reaches a large energy density of 84.2 Wh Kg−1 at a power density of 1.0 kW kg−1, indicating its great potential application. Image 1 • A novel three-dimension hybrid carbon material consisting of RGO and N-doped carbon nanoflower was fabricated. • As-prepared hybrid carbon delivers good capacitive performance both in the KOH and ionic liquid electrolyte. • The symmetric supercapacitor exhibits integrated large energy and power density. • The enhancement on capacitive performance is ascribed to the efficient transport pathway of electrons and ions. [ABSTRACT FROM AUTHOR]

Abstract The relationships among the production of methane, the physicochemical properties of coal, and the composition of microbial communities are poorly understood in methanogenic bioconversion. In this study, we investigated the changes in microbial communities during the methanogenic process of coal based on culture-dependent methods as well as the physicochemical properties of the coal samples. The process of methane production could be clearly divided into four phases (lag, log, peak, and stationary phases). The initial bacterial communities in the cultivation were predominantly Bacteroidales, Actionmycetales, and Bacillales; the archaeal community was present at values below the detection limit. However, distinct changes in bacterial communities were noted at the log phase of methane production. Bacteroides species accounted for >80% of the total bacterial community, and acetotrophic Methanosarcina was the only archaeal community. Interestingly, Clostridiales increased considerably during the first 2 weeks, but decreased thereafter, indicating that Clostridiales may play a unique role during the initial stage of methanogenic coal bioconversion. Furthermore, the final coal sample showed decreased C and O contents and increased N and H contents. Volatile and ash contents as well as microporosity were also higher than those in the initial state. These results suggested that methanogenic coal bioconversion was a complex biochemical process and that the physicochemical properties of coal were altered in methanogenic bioconversion. Moreover, these findings may facilitate the development of strategies to improve the production of biomethane utilizing coal. Highlights • Methane production was divided into lag, log, peak, and stationary phases. • Significant changes in bacterial communities were observed during the log phases. • Clostridiales increased obviously during the lag phase, but decreased thereafter. • Final coal samples showed changed chemical contents and increased microporosity. [ABSTRACT FROM AUTHOR]

Abstract A Standardized Precipitation Evapotranspiration Index (SPEI) model, which uses the FAO-56 Penman–Monteith equation to calculate potential evapotranspiration, has been developed and is considered appropriate for drought monitoring and assessment. However, the correlation of SPEI to total water storage (TWS) across multiple timescales, derived from future climate scenarios, is still unclear for China. In this study, the correlation of SPEI on different timescales (1-, 3-, 6-, 12-, 24- and 48-month) to TWS projected by a global climate model [the Community Climate System Model, version 4 (CCSM4)] under two representative concentration pathway scenarios (RCP2.6 and RCP8.5) for the period 2021–2100 in China is analyzed. The results show that, in general, SPEI is highly correlated with CCSM TWS in most of China (especially in eastern China) at the 12-month timescale, and is therefore regarded as an adequate indicator for representing situations of water resources and evaluating hydrological droughts. At the 12-month timescale, the correlations of SPEI to CCSM TWS vary across different river basins; and the variations in the pattern of correlations are greater due to faster warming and greater precipitation under RCP8.5. It is hoped that this article will provide guidance on the use of SPEI for detecting the impacts of future climate change on drought severity in China. Highlights • SPEI is highly correlated with CCSM TWS on 12-month timescale in general. • Good fitting effects mainly show in eastern river basins in China. • The variation of correlation patterns is greater under RCP8.5 than that under RCP2.6 • SPEI gives a good indication of hydrological variability in China's future. [ABSTRACT FROM AUTHOR]

Microbial communities of sludge samples from a full-scale anaerobic digestion (AD) fed with primary sludge (PS) and excess sludge (ES) were analyzed using qPCR and MiSeq. The results showed that the microbial composition of digested sludge remained relatively stable but was partially changed by microbial immigration from feeding sludge. The dominant archaea in the digested sludge were largely the same as those in the feeding sludge, but their abundances differed markedly. The dominant fungal genera in the digested sludge were different from those in PS but were similar to those in ES. Various differences in bacterial community differences between digested sludge and PS/ES were observed. Notably, this study is the first to suggest Verrucomicrobia is the predominant bacterial phylum in the digested sludge, and that numerous unreported microorganisms belonging to the order LD1-PB3 existed in this AD system and potentially played roles in the processes of hydrolysis, fermentation, and acetogenesis. [ABSTRACT FROM AUTHOR]

In this study, a novel γ-Fe 2 O 3 /biochar (BF γ) composite by a plant in-situ enrichment and one-step pyrolysis strategy was prepared, which was applied as a photocatalyst to activate peroxymonosulfate (PMS) for the degradation of p-chlorophenol (4-CP) under visible light irradiation (BF γ /PMS/Vis) system. The characterization results exhibited that γ-Fe 2 O 3 with localized carbon doping was evenly embedded in biochar during the pyrolysis. BF γ exhibited better photoresponse properties than biochar (BC) and γ-Fe 2 O 3. The removal efficiency of this system for 4-CP reached 96.41% under optimal conditions. This system showed high removal efficiency with a wide pH range (3.0–13.0) and under conditions of different organic pollutants. It also showed strong resistance to interference with co-existing inorganic ions and humic acid (HA). Electron paramagnetic resonance (EPR) and radical scavenging experiments revealed that the reactive oxygen species (ROS) in this system included SO 4 -·, ·OH, ·O 2 - and 1O 2. The density functional theoretical (DFT) calculations further revealed the promotion of localized carbon doping in γ-Fe 2 O 3 on electron transfer and photoresponse, including C-O bond (d=1.29 Å), C-Fe bond (d=1.80 Å) and band gap value (E gap < 0.72 eV). This study provides new insights into constructing environmentally-friendly catalysts and the possibility of the solid waste recycling for other wetland plants. [Display omitted] • The photocatalyst was obtained by biochar in-situ enriched with iron. • The BF γ /PMS/Vis system exhibited excellent performance and applicability. • The 4-CP decomposition pathway and reactive mechanism were proposed. • The formed C-O (C-Fe) bond and reduced band gap value enhanced the photocatalytic performance by DFT calculations. [ABSTRACT FROM AUTHOR]

Currently, researchers have focused on electrokinetic (EK) bioremediation due to its potential to remove a wide-range of pollutants. Further, to improve their performance, synthetic surfactants are employed as effective additives because of their excellent solubility and mobility. Synthetic surfactants have an excessive position in industries since they are well-established, cheap, and easily available. Nevertheless, these surfactants have adverse environmental effects and could be detrimental to aquatic and terrestrial life. Owing to social and environmental awareness, there is a rising demand for bio-based surfactants in the global market, from environmental sustainability to public health, because of their excellent surface and interfacial activity, higher and stable emulsifying property, biodegradability, non- or low toxicity, better selectivity and specificity at extreme environmental conditions. Unfortunately, challenges to biosurfactants, like expensive raw materials, low yields, and purification processes, hinder their applicability to large-scale. To date, extensive research has already been conducted for production scale-up using multidisciplinary approaches. However, it is still essential to research and develop high-yielding bacteria for bioproduction through traditional and biotechnological advances to reduce production costs. Herein, this review evaluates the recent progress made on microbial-surfactants for bioproduction scale-up and provides detailed information on traditional and advanced genetic engineering approaches for cost-effective bioproduction. Furthermore, this study emphasized the role of electrokinetic (EK) bioremediation and discussed the application of BioS-mediated EK for various pollutants remediation. [Display omitted] • Recent biotechnological advances for production scale-up have been discussed. • Currently available tools from traditional to advanced genetic engineering have been summarized. • Straw biomass valorization as a renewable low-cost feedstock's has been described. • BioS are promising alternative to synthetic surfactants for EK remediation additives. • BioS-assisted EK remediation of various environmental pollutants has been reviewed. [ABSTRACT FROM AUTHOR]

In this study, pyrosequencing combined with clone library analysis, qPCR, and fluorescent in situ hybridization (FISH) were performed to identify detailed changes of bacterial and filamentous bacterial communities in activated sludge (AS) in 3 types of typical AS samples: sludge bulking (B-AS), excessive bulking (EB-AS), and non-bulking (N-AS). Sludge bulking resulted in a decrease in total bacterial numbers from (6.4 ± 0.18) × 10 8 gene copies/mL in N-AS to (2.4 ± 0.22) × 10 8 in EB-AS and a decrease in bacterial diversity from 2757 OTUs in N-AS to 2217 OTUs in EB-AS. With the occurrence of sludge bulking, Actinobacteria and Firmicutes increased sharply, whereas Proteobacteria , which was the predominant phylum in N-AS, decreased markedly. In addition, Nitrospirae , a major lineage of the nitrite-oxidizing bacteria, had quite a low abundance in EB-AS (0.15%), while it was relatively high in N-AS (1.17%). On the other hand, filamentous bacteria accounted for 28.77% and 5.72% of total sequences in EB-AS and N-AS, respectively. More interestingly, 11 types of filamentous bacteria were always present in 3 types of typical AS samples from different stages of sludge bulking, and most of them enriched in EB-AS compared to N-AS. It is noteworthy that, in addition to the frequently reported filamentous bacteria such as Candidatus M. parvicella and Tetrasphaera , novel filamentous species of Trichococcus might exist in this bulking WWTP. Our results reveal that sludge bulking are derived from diverse taxa, which expands previous understanding and provides new insight into the underlying complications of the bulking phenomenon in AS. [ABSTRACT FROM AUTHOR]

Bio-foaming is a major problem in solid separation in activated sludge (AS) wastewater treatment systems. Understanding the changes in bacterial communities during sludge foaming is vital for explaining foam formation. Changes in bacterial communities in the foam, corresponding foaming AS, and non-foaming AS in a seasonal foaming wastewater treatment plant (WWTP) in Northern China were investigated by high-throughput pyrosequencing and molecular quantification-based approaches. We found that bacterial communities of the foam and the corresponding foaming AS were similar but markedly different from those of the non-foaming AS. Actinobacteria was the predominant phylum in the foam and the corresponding foaming AS, whereas Proteobacteria was predominant in the non-foaming AS. Similar to the results of most previous studies, our results showed that Candidatus ' Microthrix parvicella' was the predominant filamentous bacteria in the foam and the corresponding foaming AS and was significantly enriched in the foam compared to the corresponding foaming AS. Its abundance decreased gradually with a slow disappearance of sludge foaming, indicating that its overgrowth had a direct relationship with sludge foaming. In addition to Candidatus M. parvicella, Tetrasphaera and Trichococcus might play a role in sludge foaming, because they supported the changes in AS microbial ecology for foam formation. The effluent water quality of the surveyed plant remained stable during the period of sludge foaming, but the microbial consortia responsible for nitrogen and phosphorus transformation and removal markedly changed compared to that in the non-foaming AS. This study adds to the previous understanding of bacterial communities causing foaming in WWTPs. [ABSTRACT FROM AUTHOR]

Microbial communities associated with biogenic coalbed methane (CBM) have been investigated extensively by sampling produced water and coal samples. However, little is known about the microbial communities associated with CBM gas. In this study, we employed pyrosequencing and real-time polymerase chain reaction to investigate the microbial communities in CBM gas from a CBM field associated with Ordos Basin in China, where biogenic CBM had been identified and methanogens and related bacteria had been found to be present in coal and produced water samples. The pyrosequencing results revealed that the GOM_Arc_I group, with 99.3% archaeal sequence reads, was the predominant archaea in gas samples. The main bacteria present in gas samples were Proteobacteria. In particular, the genus Herbaspirillum comprised approximately 76% of bacterial sequences. Most of the detected bacteria had the potential to degrade aromatic and cellulose-derived compounds in coal and promote nitrogen cycling in coalbeds. The microbial diversity in gas was lower than that in coal and produced water, and significant differences were observed in the microbial communities in gas. These results provided insights into the archaeal and bacterial communities associated with CBM gas at this location and may improve our understanding of the current status of archaeal and bacterial communities in CBM fields. [ABSTRACT FROM AUTHOR]

Pyrolysate from waste cotton was acid hydrolyzed and detoxified to yield pyrolytic sugars, which were fermented to ethanol by the strain Escherichia coli ACCC 11177. Mathematical models based on the fermentation data were also constructed. Pyrolysate containing an initial levoglucosan concentration of 146.34 g/L gave a glucose yield of 150 % after hydrolysis, suggesting that other compounds were hydrolyzed to glucose as well. Ethyl acetate-based extraction of bacterial growth inhibitors with an ethyl acetate/hydrolysate ratio of 1:0.5 enabled hydrolysate fermentation by E. coli ACCC 11177, without a standard absorption treatment. Batch processing in a fermenter exhibited a maximum ethanol yield and productivity of 0.41 g/g and 0.93 g/L·h, respectively. The cell growth rate ( r) was consistent with a logistic equation $$ {r}_x=0.21\left(1-\frac{X}{3.75}\right)X $$, which was determined as a function of cell growth ( X). Glucose consumption rate ( r) and ethanol formation rate ( r) were accurately validated by the equations $$ {r}_s=0.25\frac{dX}{dt}+0.47X $$ and $$ {r}_p=0.05\frac{dX}{dt}+0.29X $$, respectively. Together, our results suggest that combining mathematical models with fermenter fermentation processes can enable optimized ethanol production from cellulosic pyrolysate with E. coli. Similar approaches may facilitate the production of other commercially important organic substances. [ABSTRACT FROM AUTHOR]

The microbial communities and biogenic methane potential of a gas coal mine were investigated by cultivation-independent and cultivation-dependent approaches. Stable carbon isotopic analysis indicated that in situ methane in the coal mine was dominantly of a thermogenic origin. However, a high level of diversity of bacteria and methanogens that were present in the coal mine was revealed by 454 pyrosequencing, and included various fermentative bacteria in the phyla of Actinobacteria , Bacteroidetes , Firmicutes , and Proteobacteria , and acetotrophic, hydrogenotrophic, and methylotrophic methanogens. Methane was produced in enrichments of mine water samples supplemented with acetate under laboratory conditions. The microbial flora obtained from the enrichments could stimulate methane formation from coal samples. 16S rRNA gene clone library analysis indicated that the microbial community from coal cultivation samples supplemented with the enriched microbial consortium was dominated by the anaerobic fermentative Clostridiales and facultative acetoclastic Methanosarcina . This study suggests that the biogenic methane potential in the thermogenic-gas coal mine could be stimulated by the indigenous microorganisms. [ABSTRACT FROM AUTHOR]

The activity of methanogens and related bacteria which inhabit the coal beds is essential for stimulating new biogenic coal bed methane (CBM) production from the coal matrix. In this study, the microbial community structure and methanogenesis were investigated in Southern Qinshui Basin in China, and the composition and stable isotopic ratios of CBM were also determined. Although geochemical analysis suggested a mainly thermogenic origin for CBM, the microbial community structure and activities strongly implied the presence of methanogens in situ. 454 pyrosequencing analysis combined with methyl coenzyme-M reductase ( mcrA) gene clone library analysis revealed that the archaeal communities in the water samples from both coal seams were similar, with the dominance of hydrogenotrophic methanogen Methanobacterium. The activity and potential of these populations to produce methane were confirmed by the observation of methane production in enrichments supplemented with H + CO and formate, and the only archaea successfully propagated in the tested water samples was from the genus Methanobacterium. 454 pyrosequencing analysis also recovered the diverse bacterial communities in the water samples, which have the potential to play a role in the coal biodegradation fueling methanogens. These results suggest that the biogenic CBM was generated by coal degradation via the hydrogenotrophic methanogens and related bacteria, which also contribute to the huge CBM reserves in Southern Qinshui Basin, China. [ABSTRACT FROM AUTHOR]

In this paper, we propose an optically controlling broadband terahertz modulator of a layer-dependent PtSe2 nanofilm based on a high-resistance silicon substrate. Through optical pump and terahertz probe system, the results show that compared with 6-, 10-, and 20-layer films, a 3-layer PtSe2 nanofilm has better surface photoconductivity in the terahertz band and has a higher plasma frequency ωp of 0.23 THz and a lower scattering time τs of 70 fs by Drude–Smith fitting. By the terahertz time-domain spectroscopy system, the broadband amplitude modulation of a 3-layer PtSe2 film in the range of 0.1–1.6 THz was obtained, and the modulation depth reached 50.9% at a pump density of 2.5 W/cm2. This work proves that PtSe2 nanofilm devices are suitable for terahertz modulators. [ABSTRACT FROM AUTHOR]

Abstract: The dynamics of bacterial and eukaryotic community associated with each step of a water purification plant in China was investigated using 454 pyrosequencing and qPCR based approaches. Analysis of pyrosequencing revealed that a high degree diversity of bacterial and eukaryotic communities is present in the drinking water treatment process before sand filtration. In addition, the microbial compositions of the biofilm in the sand filters and those of the water of the putatively clear tanks were distinct, suggesting that sand filtration and chlorination treatments played primary roles in removing exposed microbial communities. Potential pathogens including Acinetobacter, Clostridium, Legionella, and Mycobacterium, co-occurred with protozoa such as Rhizopoda (Hartmannellidae), and fungi such as Penicillium and Aspergillus. Furthermore, this study supported the ideas based on molecular level that biofilm communities were different from those in corresponding water samples, and that the concentrations of Mycobacterium spp., Legionella spp., and Naegleria spp. in the water samples declined with each step of the water treatment process by qPCR. Overall, this study provides the first detailed evaluation of bacterial and eukaryotic diversity at each step of an individual potable water treatment process located in China. [Copyright &y& Elsevier]

Microorganism in drinking water distribution system may colonize in biofilms. Bacterial 16S rRNA gene diversities were analyzed in both water and biofilms grown on taps with three different materials (polyvinyl chloride (PVC), stainless steel, and cast iron) from a local drinking water distribution system. In total, five clone libraries (440 sequences) were obtained. The taxonomic composition of the microbial communities was found to be dominated by members of Proteobacteria (65.9-98.9 %), broadly distributed among the classes Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. Other bacterial groups included Firmicutes, Acidobacteria, Bacteroidetes, Cyanobacteria, and Deinococcus-Thermus. Moreover, a small proportion of unclassified bacteria (3.5-10.6 %) were also found. This investigation revealed that the bacterial communities in biofilms appeared much more diversified than expected and more care should be taken to the taps with high bacterial diversity. Also, regular monitor of outflow water would be useful as potentially pathogenic bacteria were detected. In addition, microbial richness and diversity in taps ranked in the order as: PVC < stainless steel < cast iron. All the results interpreted that PVC would be a potentially suitable material for use as tap component in drinking water distribution system. [ABSTRACT FROM AUTHOR]

To identify the methanogenic pathways present in a deep coal bed methane (CBM) reservoir associated with Eastern Ordos Basin in China, a series of geochemical and microbiological studies was performed using gas and water samples produced from the Liulin CBM reservoir. The composition and stable isotopic ratios of CBM implied a mixed biogenic and thermogenic origin of the methane. Archaeal 16S rRNA gene analysis revealed the dominance of the methylotrophic methanogen Methanolobus in the water produced. The high potential of methane production by methylotrophic methanogens was found in the enrichments using the water samples amended with methanol and incubated at 25 and 35 °C. Methylotrophic methanogens were the dominant archaea in both enrichments as shown by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE). Bacterial 16S rRNA gene analysis revealed that fermentative, sulfate-reducing, and nitrate-reducing bacteria inhabiting the water produced were a factor in coal biodegradation to fuel methanogens. These results suggested that past and ongoing biodegradation of coal by methylotrophic methanogens and syntrophic bacteria, as well as thermogenic CBM production, contributed to the Liulin CBM reserves associated with the Eastern Ordos Basin. [ABSTRACT FROM AUTHOR]

Abstract: In order to understand the microbial communities in drinking water biofilms, both eukaryotic and bacterial communities in three faucet biofilms were characterized by 454 pyrosequencing and quantitative PCR approaches. Microbial assemblages of the biofilms were dominated by bacteria, with Sphingomonadales, Rhizobiales, and Burkholderiales comprising the major bacterial populations. Although about 2years of biofilm development occurred, the microbial community at site WSW still demonstrates the characteristics of a young biofilm community, e.g. low biomass, abundant aggregating bacteria (Blastomonas spp. and Acidovorax spp.) etc. Hartmannella of amoebae was the dominant eukaryotic predator in the biofilms, and correlated closely with biofilm bacterial biomass. Nonetheless, there was no obvious association of pathogens with amoebae in the faucet biofilms. In contrast, residual chlorine seems to be a dominant factor impacting the abundance of Legionella and Mycobacterium, two primary potential opportunistic pathogens detected in all faucet biofilms. [Copyright &y& Elsevier]

In this study, to give insight into the bacterial diversity of biofilms from full-scale drinking water distribution systems (DWDSs), the bacterial community compositions of biofilms from two urban DWDSs (Guangzhou and Beijing, China) were determined using a 16S rRNA gene library technique. Meanwhile, the occurrence and diversity of mycobacteria were also analyzed by a -specific hsp gene assay. The biofilms from the full-scale DWDSs have complex bacterial populations. Proteobacteria was the common and predominant group in all biofilm samples, in agreement with previous reports. The community structures of bacteria at the three sites in Guangzhou DWDS were significantly different, despite the similar physicochemical properties of portable water. Some abundant and peculiar bacterial phylotypes were noteworthy, including , , and , members of which are rarely found in DWDSs and their roles in DWDS biofilms are still unclear. The diversity of Mycobacterium species in biofilm samples was rather low. and were the primary Mycobacterium species in Guangzhou and Beijing biofilms, respectively, indicating that M. arupense may be more resistant to chloride than M. gordonae. [ABSTRACT FROM AUTHOR]

Abstract: Among 44 yeast strains tested for ability to degrade textile dyes, two novel strains, Pseudozyma rugulosa Y-48 and Candida krusei G-1, were selected and identified because they exhibited excellent color removal from various dyes. P. rugulosa Y-48 and C. krusei G-1 could remove the reactive azo dye, Reactive Brilliant Red K-2BP , giving up to 99% decolorization in 24h. P. rugulosa Y-48 could also remove 22–98% of seven other dyes and C. krusei G-1 62–94%. Of the seven dyes, all azo dyes were most easily decolorized by these yeasts. Further analysis showed that decolorization of the dyes tested proceeded primarily by biodegradation. [Copyright &y& Elsevier]

Acid-hydrolysis of cellulosic pyrolysate to glucose and its fermentation to ethanol were investigated. The maximum glucose yield (17.4%) was obtained by the hydrolysis with 0.2 mol/l sulfuric acid using autoclaving at 121 °C for 20 min. The fermentation by Saccharomyces cerevisiae of a hydrolysate medium containing 31.6 g/l glucose gave 14.2 g/l ethanol after 24 h, whereas the fermentation of the medium containing 31.6 g/l pure glucose gave 13.7 g/l ethanol after 18 h. The results showed that acid-hydrolyzed pyrolysate could be used for ethanol production. Different nitrogen sources were evaluated and the best ethanol concentration (15.1 g/l) was achieved by single urea. S. cerevisiae (R) was obtained by adaptation of S. cerevisiae to the hydrolysate medium for 12 times, and 40.2 g/l ethanol was produced by it in the fermentation with the hydrolysate medium containing 95.8 g/l glucose, which was about 47% increase in ethanol production compared to its parent strain. [Copyright &y& Elsevier]

The acid hydrolysis of cellulosic pyrolysate to glucose and its fermentation to ethanol were investigated. The maximum glucose yield (17.4%) was obtained by the hydrolysis with 0.2 mol sulfuric acid per liter pyrolysate using autoclaving at 121 °C for 20 min. The fermentation by Saccharomyces cerevisiae of a hydrolysate medium containing 31.6 g/l glucose gave 14.2 g/l ethanol in 24 h, whereas the fermentation of the medium containing 31.6 g/l pure glucose gave 13.7 g/l ethanol in 18 h. The results showed that the acid-hydrolyzed pyrolysate could be used for ethanol production. Different nitrogen sources were evaluated and the best ethanol concentration (15.1 g/l) was achieved by single urea. S. cerevisiae (R) was obtained by adaptation of S. cerevisiae to the hydrolysate medium for 12 times, and 40.2 g/l ethanol was produced by S. cerevisiae (R) in the fermentation with the hydrolysate medium containing 95.8 g/l glucose, which was about 47% increase in ethanol production compared to its parent strain. [Copyright &y& Elsevier]

Cellulosic pyrolysate containing levoglucosan was chemically hydrolyzed and a maximum glucose yield of 17.35% was obtained by the hydrolysis with 0.2 mol/l H2SO4 at 121°C for 20 min. The total initial glucose was maintained at 41.9 g/l by diluting the hydrolysate. Ten detoxification methods were employed including either single addition of solid Ca(OH)2 (to pH 6.0 or 10.4) or its combinations with absorbents. The neutralization+diatomite shaking method gave the hydrolysate which was most completely fermented by Saccharomyces cerevisiae and Pichia sp. YZ-1. The maximal ethanol yield of 0.45 g/g glucose was obtained by S. cerevisiae. [Copyright &y& Elsevier]

The continuous surge in global energy demand, fossil fuel depletion, and related climate change issues have oriented the worldwide researchers' endeavors to the investigation and development of sustainable and co-effective technology to satisfy the global energy needs. Referring to the non-toxic properties of hydrogen, it is considered as a suitable renewable energy source that could replace fossil fuel-based energy. It is the cleanest energy carrier, combustible with high calorific value, high energy yield. Producing biohydrogen energy from renewable resources such as lignocellulosic agricultural residues could be a sustainable carbon-neutral most cost-effective approach. Dark fermentation has been widely applied as a promising eco-friendly technique to produce biohydrogen from agricultural residues. However, it has shown drawbacks owing to the recalcitrance of lignocellulose structure, and the accumulation of acid-rich intermediate by-products. Microbial electrolysis cells use bio-electrochemical reactions to upgrade H 2 production in a dark fermentation reactor by promoting further decomposition of the generated volatile fatty acids. Therefore, integrating microbial electrohydrogenesis with dark fermentation can be a promising strategy to optimize the straw biomass conversion to biohydrogen. This review aims in delineating the structural composition and recalcitrance of the agricultural residues and their major effects on biohydrogen production. It summarizes all possible pre-treatment methods of the lignocellulosic agricultural residues; elucidates the stable operational conditions of microbial electrolysis cell and dark fermentation integrated system and discusses its performance for biohydrogen production. This study also reviewed the current technical challenges of this integrated system application and suggested sustainable solutions towards its industrial implementation. [Display omitted] • Microbial electrohydrogenesis and dark fermentation integrated system enhances biohydrogen production from straw biomass. • MEC-DF effluent could serve as an alternative cheap biofertilizer to the costly commercial ones. • Lignocellulosic agricultural residues can be considered as a potential bioresource for renewable biohydrogen energy. • The appropriate pretreatment of the agricultural residue improves biohydrogen production efficiency. [ABSTRACT FROM AUTHOR]

Cyanobacterial biomass is a promising natural resource for power generation, through the reactions bio-catalyzed by electrochemically active bacteria (EAB). However, the major limitation is the involvement of Microcystin-LR (MC-LR) in inhibiting EAB activation. In this work, toxic M. aeruginosa biomass was employed as analyte of a microbial fuel cell (MFC), and sodium acetate was applied as easy-to-biodegrade co-substrate to alleviate the MC-LR stress on EAB survival. The running stability was continuously enhanced with the increment of co-substrate concentration. The sufficient co-substrate supply (6.0 mM) eliminated the negative effects of MC-LR on the cyanobacteria biomass fed-MFC performance; it contributed 12.7% extension on the electric cyclic terms and caused the productions of the power density which was comparable and even 3.8% higher than its corresponding control (MFC treated with acetate alone). The co-substrate addition also increased coulombic efficiency by 60.1%, microcystin-LR removal efficiency increased by 64.7%, and diversified the microbial community with more species able to biodegrade the MC-LR, bio-transforming the metabolites and EAB. Microcystin-degrading bacteria, such as Sphingopyxis sp. , Burkholderia-Paraburkholderia , and Bacillus sp. , were remarkably increased, and EAB, including Shewanella sp. , Desulfovibrio desulfuricans , Aeromonas hydrophila , were also much more enriched in co-substrate use protocol. Therefore, this study verified a co-substrate strategy for simultaneously eliminating MC-LR toxin and enhancing bioelectricity generation from cyanobacterial biomass via an MFC. Unlabelled Image • Toxic cyanobacteria converted to electricity via EAB with aid of co-substrate. • Co-substrate enhanced energy recovery from cyanobacteria biomass via an MFC. • Co-substrate increased MC-LR removal efficiency by 64.7% and so eliminated the toxins in the analyte. • Co-substrate promoted MC-LR degrading bacteria and EAB cell enrichment. • Coulombic efficiency increased by 60.1% when the co-substrate was sufficient. [ABSTRACT FROM AUTHOR]

Biogenic methane in shallow shale reservoirs has been proven to contribute to economic recovery of unconventional natural gas. However, whether the microbes inhabiting the deeper shale reservoirs at an average depth of 4.1 km and even co-occurring with sulfate-reducing prokaryote (SRP) have the potential to produce biomethane is still unclear. Stable isotopic technique with culture-dependent and independent approaches were employed to investigate the microbial and functional diversity related to methanogenic pathways and explore the relationship between SRP and methanogens in the shales in the Sichuan Basin, China. Although stable isotopic ratios of the gas implied a thermogenic origin for methane, the decreased trend of stable carbon and hydrogen isotope value provided clues for increasing microbial activities along with sustained gas production in these wells. These deep shale-gas wells harbored high abundance of methanogens (17.2%) with ability of utilizing various substrates for methanogenesis, which co-existed with SRP (6.7%). All genes required for performing methylotrophic, hydrogenotrophic and acetoclastic methanogenesis were present. Methane production experiments of produced water, with and without additional available substrates for methanogens, further confirmed biomethane production via all three methanogenic pathways. Statistical analysis and incubation tests revealed the partnership between SRP and methanogens under in situ sulfate concentration (~ 9 mg/L). These results suggest that biomethane could be produced with more flexible stimulation strategies for unconventional natural gas recovery even at the higher depths and at the presence of SRP. [ABSTRACT FROM AUTHOR]

• Poultry-associated markers were systematically assessed. • Modified marker AV4143 here was suitable for microbial source tracking of avian. • LA35 showed high sensitivity in poultry litter, but not in poultry faeces. • Ckmito and ND5-CD were combined to identify faecal pollution from poultry. A suitable marker for microbial source tracking (MST) remains difficult to find in China due to the geographical variability of markers. 162 faecal and litter samples were collected from five different regions in China to identify the faecal pollution from poultry with nine published molecular markers for MST. All samples tested were positive for both universal markers BacUni and MI50, but BacUni was detected with higher gene copies. Of the avian-associated AV4143 and GFD assays, the AV4143 was modified here with the accuracy of 88% which proved its potential in identifying faecal pollution from avian. For all poultry-associated markers tested, the best performance characteristics were shown in marker Ckmito (accuracy of 97%), followed by ND5-CD (accuracy of 88%), and finally LA35 and Chicken-Bac (accuracy of ≤ 77%). A combination of mitochondrial DNA (mtDNA) markers Ckmito and ND5-CD is recommended to differentiate the contamination caused by poultry. LA35 was more sensitive in poultry litter (100%) than in poultry faeces (21%). Our findings regarded BacUni, AV4143, and a combination of Ckmito and ND5-CD as the best performing universal, avian, and poultry assays, respectively. Suitable molecular markers could assist with efforts to determine the faecal pollution sources in environmental monitoring. [ABSTRACT FROM AUTHOR]

Biohydrogen is a renewable and clean energy source that can be produced from cheap and abundantly available lignocellulose biomass. However, the complex structure of lignocellulose requires various physicochemical and biological pretreatments, as it exhibits significant resistance to microbial degradation. Biosurfactants can play a vital role in facilitating the microbial degradation of lignocellulose and inducing enzymatic hydrolysis. In addition, they can lower the surface tension to impede lignin-cellulase interactions and alter the lignin characteristics. Indeed, the application of lipopeptide biosurfactants to enhance hydrogen production from lignocellulose biomass is poorly studied. Thus, this study investigates the influence of lipopeptide biosurfactants on biohydrogen enhancement from lignocellulose biomass and their impact on short-chain fatty acid generation during anaerobic dark fermentation. Subsequently, Illumina HiSeq 2500 sequencing was employed to analyze the structure of microbial community and diversity significantly affected by the presence or absence of aided biosurfactants. Results revealed that the lipopeptide biosurfactant significantly improved the cumulative biogas and hydrogen production. The maximum cumulative hydrogen yield was achieved in lipopeptide-assisted bioreactors including BioR_3, BioR_2, and BioR_4 (i.e., 4.68, 4.56, and 4.50 mmol/2 g of substrate, respectively), showing an increase of 30.79% to 36.03% higher than BioR_1 (3.44 mmol). In addition, lipopeptide biosurfactants also impacted the short-chain fatty acid generation, where acetic acid, propionic acid, and isobutyric acid were found as major acids. On the other hand, various bacterial phyla, including Firmicutes, Proteobacteria, Actinobacteria, Chloroflexi, Planctomycetota, and Acidobacteriota, were detected in all bioreactors. Among the phyla, Firmicutes were predominated (54.74% to 86.38%) in lipopeptide-assisted bioreactors, indicating that biosurfactants substantially influenced the microbial community structure during hydrogen production. Besides, Ruminiclostridium and Bacillus were significantly promoted in lipopeptide-assisted bioreactors, representing efficient lignocellulose-degrading and hydrogen-producing genera. Conclusively, this study offers valuable insights into the underlying mechanism through which lipopeptide biosurfactants actively participate in biohydrogen production and illuminates the variations occurring within microbial communities. [ABSTRACT FROM AUTHOR]

• A bifunction switchable terahertz device is designed, which can realize broadband absorption and polarization conversion. • The absorption exceeding 90% in the 1.03-2.62 THz range is insensitive to both incident and polarization angles. • When VO 2 is in the insulate state, the linear-cross polarization conversion can be realized in the range of 1.81-2.39 THz. • The triple-band linear-circular polarization conversion can also be obtained. A broadband absorption and polarization conversion switchable terahertz metamaterial device can be obtained by introducing vanadium dioxide with the metal to insulate phase transition. As the vanadium dioxide is in the metallic state, the device is a broadband absorber with over 90% absorption from 1.03 THz to 2.62 THz, and the broadband absorption performance is not sensitive to both the oblique incident angle and polarization. When vanadium dioxide is in insulate state, the device performs as a polarization converter with two functions of linear to cross polarization and linear to circular polarization conversion. The polarization conversion efficiency of linear to cross polarization conversion is above 90% from 1.81 THz to 2.39 THz, while the ellipticity of linear to circular polarization conversion is over 0.9 in the ranges of 0.75–1.69 THz, 2.48–2.59 THz and 2.81–2.90 THz, respectively. The proposed bifunctional device provides the potential in THz devices with tunable and diverse functionalities. [ABSTRACT FROM AUTHOR]

Rational design of sulfur hosts for effectively confining lithium polysulfides (LiPS) and optimizing the sluggish sulfur kinetics is still a major challenge in lithium–sulfur batteries (LSBs). In this work, a simple strategy of introducing single Mo–N4 atoms into N‐doped carbon nano‐flower matrix (Mo‐N‐CNF) as sulfur host cathode materials is developed to realize high‐performance LSBs. These single Mo–N4 atoms have been demonstrated to regulate the hydrophilic nature, Li‐ion diffusion, adsorption capacity, and catalytic conversion of polysulfides via experimental evidences and theoretical calculations. The resulting Mo‐N‐CNF with high loading content of sulfur (>72 wt.%) exhibits a high specific capacity (1248 mAh g–1 at 0.2 C) and excellent rate capability (715 mAh g–1 at 5 C). More importantly, the outstanding cycling performance with a low attenuation rate of only 0.004% per cycle over 400 cycles at 4.27 mA cm–2 is achieved with the area sulfur loading of 5.1 mg cm–2. This work demonstrates a viable strategy for using single atoms‐based carbon materials with high exposed sites as multiple captors for LiPS and an efficient accelerator for sulfur redox kinetics toward next‐generation LSBs with boosted electrochemical performance. [ABSTRACT FROM AUTHOR]

Early embryos undergo extensive epigenetic reprogramming to achieve gamete‐to‐embryo transition, which involves the loading and removal of histone variant H2A.Z on chromatin. However, how does H2A.Z regulate gene expression and histone modifications during preimplantation development remains unrevealed. Here, by using ultra‐low‐input native chromatin immunoprecipitation and sequencing, the genome‐wide distribution of H2A.Z is delineated in mouse oocytes and early embryos. These landscapes indicate that paternal H2A.Z is removed upon fertilization, followed by unbiased accumulation on parental genomes during zygotic genome activation (ZGA). Remarkably, H2A.Z exhibits hierarchical accumulation as different peak types at promoters: promoters with double H2A.Z peaks are colocalized with H3K4me3 and indicate transcriptional activation; promoters with a single H2A.Z peak are more likely to occupy bivalent marks (H3K4me3+H3K27me3) and indicate development gene suppression; promoters with no H2A.Z accumulation exhibit persisting gene silencing in early embryos. Moreover, H2A.Z depletion changes the enrichment of histone modifications and RNA polymerase II binding at promoters, resulting in abnormal gene expression and developmental arrest during lineage commitment. Furthermore, similar transcription and accumulation patterns between mouse and porcine embryos indicate that a dual role of H2A.Z in regulating the epigenome required for proper gene expression is conserved during mammalian preimplantation development. [ABSTRACT FROM AUTHOR]

1,6-Anhydro- N -acetylmuramic acid kinase (AnmK) is the unique enzyme that marks the recycling of the cell wall of Escherichia coli . Here, 81 fungal AnmK-like kinase sequences from 57 fungal species were searched in the NCBI database and a phylogenetic tree was constructed. The three-dimensional structure of an AnmK-like kinase, levoglucosan kinase (LGK) of the yeast Lipomyces starkeyi , was modeled; molecular docking revealed that AnmK and LGK are conserved proteins, and 187Asp, 212Asp are enzymatic residues, respectively. Analysis suggests that 1,6-anhydro- N -acetylglucosamine (anhGlcNAc) and/or 1,6-anhydro-β- d -glucosamine (anhGlcN) would be the appropriate substrates of AnmK-like kinases. Also, the counterparts of other characteristic enzymes of cell wall recycling of bacteria were found in fungi. Taken together, it is proposed that a putative recycling of anhGlcNAc/anhGlcN, which is associated with the hydrolysis of cell walls, exists in fungi. This computational analysis will provide new insights into the metabolism of fungal cell walls. [ABSTRACT FROM AUTHOR]

In recent years, filamentous algae blooms and microplastics (MPs) pollution have become two major ecological and environmental problems in urban water systems. In order to solve these two problems at the same time, this study explored the loading capacity of MPs on fresh filamentous algae, and successfully synthesized magnetic filamentous algae biochar loading with Fe 3 O 4 by hydrothermal method, with the purpose of removing MPs from water. The magnetic filamentous algal biochar was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and so on. Experiments on adsorption kinetics, adsorption isotherms and optimum pH were carried out to explore the adsorption mechanism of MPs on magnetic filamentous algal biochar. The adsorption kinetics and adsorption isotherm models were evaluated, and the selection criterion for the appropriate model was determined by using the residual sum of squares (RSS) and Bayesian information criterion (BIC). Microscope images revealed that fresh filamentous algae could interact with MPs in the form of entanglement, adhesion and encapsulation. The average load of MPs in filamentous algae samples was 14.1 ± 5 items/g dry weight. The theoretical maximum adsorption capacities of polystyrene MPs (PS-MPs) by raw biochar (A500) and magnetic biochar with Fe 3 O 4 (M2A500) were 176.99 mg/g and 215.58 mg/g, respectively. The adsorbent materials gave better reusability because they could be reused up to five times. Overall, these findings have provided new insights into the use of filamentous algae for in situ remediation of fluvial MPs pollution, as well as feasible strategies for the recycling of algal waste. [Display omitted] • Removal effects of filamentous algae on MPs are investigated for the first time. • Growing filamentous algae can accumulate microplastics. • Biochar prepared from filamentous algal waste can effectively remove MPs. • Eco-friendly remediation approach is promising in reducing MP pollution. [ABSTRACT FROM AUTHOR]

Anaerobic cellulolytic microbes in the gastrointestinal tract (GT) of ruminants have been well-documented; however, knowledge of aerobic microbes with cellulolytic activities in the ruminant GT is comparably limited. Here, we unraveled aerobic cultivable cellulolytic microbes in the GT of Ujimqin sheep (Ovis aries) and evaluated the cellulolytic potential of the promising isolates. Twenty-two strains were found to possess cellulose-degrading potential by Congo-red staining and phylogenetic analysis of the 16S rDNA/ITS sequence revealed that all strains belonged to nine genera, i.e., Bacillus, Streptomyces, Pseudomonas, Lactobacillus, Brachybacterium, Sanguibacter, Rhizobium, Fusarium, and Aspergillus. Strains with high cellulolytic activity were selected to further evaluate the activities of various enzymes in lignocellulosic alfalfa hay (Medicago sativa). Among them, isolate Bacillus subtilis RE2510 showed the highest potential for cellulose degradation, considering the high endoglucanase (0.1478 ± 0.0014 IU mL−1), exoglucanase (0.1735 ± 0.0012 IU mL−1), and β-glucosidase (0.3817 ± 0.0031 IU mL−1) after 10-day incubation with alfalfa hay. A significant destruction effect of the cellulose structure and the attachment of B. subtilis RE2510 to the hay were also revealed using a scanning electron microscope. This study expands our knowledge of aerobic cellulolytic isolates from the GT of sheep and highlights their potential application as a microbial additive in the aerobic process of cellulose bioconversion. [ABSTRACT FROM AUTHOR]

To understand the impacts of different plumbing materials on long-term biofilm formation in water supply system, we analyzed microbial community compositions in the bulk water and biofilms on faucets with two different materials-polyvinyl chloride (PVC) and cast iron, which have been frequently used for more than10 years. Pyrosequencing was employed to describe both bacterial and eukaryotic microbial compositions. Bacterial communities in the bulk water and biofilm samples were significantly different from each other. Specific bacterial populations colonized on the surface of different materials. Hyphomicrobia and corrosion associated bacteria, such as Acidithiobacillus spp., Aquabacterium spp., Limnobacter thiooxidans, and Thiocapsa spp., were the most dominant bacteria identified in the PVC and cast iron biofilms, respectively, suggesting that bacterial colonization on the material surfaces was selective. Mycobacteria and Legionella spp. were common potential pathogenic bacteria occurred in the biofilm samples, but their abundance was different in the two biofilm bacterial communities. In contrast, the biofilm samples showed more similar eukaryotic communities than the bulk water. Notably, potential pathogenic fungi, i.e., Aspergillus spp. and Candida parapsilosis, occurred in similar abundance in both biofilms. These results indicated that microbial community, especially bacterial composition was remarkably affected by the different pipe materials (PVC and cast iron). [ABSTRACT FROM AUTHOR]

[Display omitted] • Phenanthrene and pyrene were significantly degraded (63.05–74.28 %) in SPS treatment. • Proteobacteria being the predominant phylum (>98 %) in all the treatment groups. • Pseudomonas and Pannonibacter were found efficient PAH-degrading genera. • Metabolites production was enhanced in SPR (more than two-fold) compared to other treatments. Biosurfactants-based bioremediation is considered an efficient technology to eliminate environmental pollutants including polycyclic aromatic hydrocarbons (PAHs). However, the precise role of rhamnolipids or lipopeptide-biosurfactants in mixed PAH dissipation, shaping microbial community structure, and influencing metabolomic profile remained unclear. In this study, results showed that the maximum PAH degradation was achieved in lipopeptide-assisted treatment (SPS), where the pyrene and phenanthrene were substantially degraded up to 74.28 % and 63.05 % respectively, as compared to rhamnolipids (SPR) and un-aided biosurfactants (SP). Furthermore, the high throughput sequencing analysis revealed a significant change in the PAH-degrading microbial community, with Proteobacteria being the predominant phylum (>98 %) followed by Bacteroidota and Firmicutes in all the treatments. Moreover, Pseudomonas and Pannonibacter were found as highly potent bacterial genera for mixed PAH degradation in SPR, SPS, and SP treatments, nevertheless, the abundance of the genus Pseudomonas was significantly enhanced (>97 %) in SPR treatment groups. On the other hand, the non-targeted metabolomic profile through UHPLC-MS/MS exhibited a remarkable change in the metabolites of amino acids, carbohydrates, and lipid metabolisms by the input of rhamnolipids or lipopeptide-biosurfactants whereas, the maximum intensities of metabolites (more than two-fold) were observed in SPR treatment. The findings of this study suggested that the aforementioned biosurfactants can play an indispensable role in mixed PAH degradation as well as seek to offer new insights into shifts in PAH-degrading microbial communities and their metabolic function, which can guide the development of more efficient and targeted strategies for complete removal of organic pollutants such as PAH from the contaminated environment. [ABSTRACT FROM AUTHOR]

Background: Bioconversion of levoglucosan, a promising sugar derived from the pyrolysis of lignocellulose, into biofuels and chemicals can reduce our dependence on fossil-based raw materials. However, this bioconversion process in microbial strains is challenging due to the lack of catalytic enzyme relevant to levoglucosan metabolism, narrow production ranges of the native strains, poor cellular transport rate of levoglucosan, and inhibition of levoglucosan metabolism by other sugars co-existing in the lignocellulose pyrolysate. The heterologous expression of eukaryotic levoglucosan kinase gene in suitable microbial hosts like Escherichia coli could overcome the first two challenges to some extent; however, no research has been dedicated to resolving the last two issues till now. Results: Aiming to resolve the two unsolved problems, we revealed that seven ABC transporters (XylF, MalE, UgpB, UgpC, YtfQ, YphF, and MglA), three MFS transporters (KgtP, GntT, and ActP), and seven regulatory proteins (GalS, MhpR, YkgD, Rsd, Ybl162, MalM, and IraP) in the previously engineered levoglucosan-utilizing and ethanol-producing E. coli LGE2 were induced upon exposure to levoglucosan using comparative proteomics technique, indicating these transporters and regulators were involved in the transport and metabolic regulation of levoglucosan. The proteomics results were further verified by transcriptional analysis of 16 randomly selected genes. Subsequent gene knockout and complementation tests revealed that ABC transporter XylF was likely to be a levoglucosan transporter. Molecular docking showed that levoglucosan can bind to the active pocket of XylF by seven H-bonds with relatively strong strength. Conclusion: This study focusing on the omics discrepancies between the utilization of levoglucosan and non-levoglucosan sugar, could provide better understanding of levoglucosan transport and metabolism mechanisms by identifying the transporters and regulators related to the uptake and regulation of levoglucosan metabolism. The protein database generated from this study could be used for further screening and characterization of the transporter(s) and regulator(s) for downstream enzymatic/genetic engineering work, thereby facilitating more efficient microbial utilization of levoglucosan for biofuels and chemicals production in future. [ABSTRACT FROM AUTHOR]

Abstract: It is generally believed that biogenic coal bed methane (CBM) is an end product of coal biodegradation by methanogenic archaea and syntrophic bacteria. In this work, the archaeal and bacterial communities of CBM reservoir associated with Ordos Basin in China were investigated using 454 pyrosequencing. Sampling produced water, coal and rock in the reservoir, a total of 46,598 sequence reads were obtained. All archaea were methanogens with the genus Methanolobus predominating. The genus consisted of 81.18% of pyrosequencing reads in water sample and >99% in coal and rock samples. Although the phylum Proteobacteria was the main component of all samples, bacterial communities in coal and rock samples were similar at the genus level, which were distinctly separated with water sample. The results strongly suggested that methylotrophic methanogenesis governed the biogenic CBM formation. The separation of microbial communities between water and coal, rock samples should be considered when investigating the process of coal biodegradation and the generation of new biogenic CBM. [Copyright &y& Elsevier]