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Recent Submissions

  • Global biodiversity patterns of marine forests of brown macroalgae

    Fragkopoulou, Eliza; Serrão, Ester A.; De Clerck, Olivier; Costello, Mark J.; Araújo, Miguel B.; Duarte, Carlos M.; Krause-Jensen, Dorte; Assis, Jorge (Global Ecology and Biogeography, Wiley, 2022-01-17) [Article]
    Aim Marine forests of brown macroalgae create essential habitats for coastal species and support invaluable ecological services. Here, we provide the first global analysis of species richness and endemicity of both the kelp and fucoid biomes. Location Global. Time period Contemporary. Major taxa studied Marine forests of brown macroalgae, formed by kelp (here defined as orders Laminariales, Tilopteridales and Desmarestiales) and fucoid (order Fucales), inhabiting subtidal and intertidal environments. Methods We coupled a large dataset of macroalgal observations (420 species, 1.01 million records) with a high-resolution dataset of relevant environmental predictors (i.e., light, temperature, salinity, nitrate, wave energy and ice coverage) to develop stacked species distribution models (stacked SDMs) and yield estimates of global species richness and endemicity. Results Temperature and light were the main predictors shaping the distribution of subtidal species, whereas wave energy, temperature and salinity were the main predictors of intertidal species. The highest regional species richness for kelp was found in the north-east Pacific (maximum 32 species) and for fucoids in south-east Australia (maximum 53 species), supporting the hypothesis that these regions were the evolutionary sources of global colonization by brown macroalgae. Locations with low species richness coincided between kelp and fucoid, occurring mainly at higher latitudes (e.g., Siberia) and the Baltic Sea, where extensive ice coverage and low-salinity regimes prevail. Regions of high endemism for both groups were identified in the Galapagos Islands, Antarctica, South Africa and East Russia. Main conclusions We estimated the main environmental drivers and limits shaping the distribution of marine forests of brown macroalgae and mapped biogeographical centres of species richness and endemicity, which largely coincided with the expectation from previous evolutionary hypotheses. The mapped biodiversity patterns can serve as new baselines for planning and prioritizing locations for conservation, management and climate change mitigation strategies, flagging threatened marine forest regions under different climate change scenarios
  • Investigation of important biochemical compounds from selected freshwater macroalgae and their role in agriculture

    Shah, Zahir; Badshah, Syed Lal; Iqbal, Arshad; Shah, Zamarud; Emwas, Abdul-Hamid M.; Jaremko, Mariusz (Chemical and Biological Technologies in Agriculture, Springer Science and Business Media LLC, 2022-01-15) [Article]
    Background Freshwater macroalgae possess a number of important secondary metabolites. They are an unexplored source of medicinal compounds. In this study, three freshwater macroalgae—$\textit{Chara vulgaris}$, $\textit{Cladophora glomerata}$ and $\textit{Spirogyra crassa}$—were collected from the river Swat and the river Kabul in the Charsadda district of Khyber Pakhtunkhwa, Pakistan. To assess the role of freshwater macroalgae in agriculture, various experiments were performed on their extracts. Methanolic extract of the three macroalgae were first analyzed through gas chromatography–mass spectrometry (GC–MS) for the presence of important medicinal secondary metabolites. The methanol based macroalgae extracts were tested for antibacterial, insecticidal, cytotoxic and phytotoxic activities. Results Initially, the algae were dried, crushed and treated with methanol for the extraction of secondary metabolites. The GC–MS results contained several important long chain fatty acids and other related long-chain hydrocarbons, such as alkanes and alkenes. Several benzene derivatives were also detected during the course of the investigation. Several of these compounds have established roles in the treatment of human ailments and can be supplied to farm animals. For example, phenylephrine is a decongestant, dilates pupils, increases blood pressure and helps in relieving hemorrhoids. Hexahydropseudoionone has uses in perfumes and other cosmetics. Several essential oils were also detected in the methanolic extract of the three macroalgae that can be utilized in various industrial products. Bioassays showed that these algal extracts—especially the $\textit{Spirogyra}$ sp. extract—contain moderate to maximum bioactivity. Conclusions Macroalgae possess important secondary metabolites with medicinal properties. These secondary metabolites can be used as biopesticides, plant growth enhancers, and remedies for various diseases in farm animals and for the control of weeds. They can be further explored for isolation and purification of useful biochemical compounds.
  • A manipulation of carotenoid metabolism influence biomass partitioning and fitness in tomato.

    Mi, Jianing; Vallarino, José G; Petřík, Ivan; Novák, Ondřej; Correa, Sandra Marcela; Chodasiewicz, Monika; Havaux, Michel; Rodriguez-Concepcion, Manuel; Al-Babili, Salim; Fernie, Alisdair R; Skirycz, Aleksandra; Moreno, Juan C (Metabolic engineering, Elsevier BV, 2022-01-15) [Article]
    Improving yield, nutritional value and tolerance to abiotic stress are major targets of current breeding and biotechnological approaches that aim at increasing crop production and ensuring food security. Metabolic engineering of carotenoids, the precursor of vitamin-A and plant hormones that regulate plant growth and response to adverse growth conditions, has been mainly focusing on provitamin A biofortification or the production of high-value carotenoids. Here, we show that the introduction of a single gene of the carotenoid biosynthetic pathway in different tomato cultivars induced profound metabolic alterations in carotenoid, apocarotenoid and phytohormones pathways. Alterations in isoprenoid- (abscisic acid, gibberellins, cytokinins) and non-isoprenoid (auxin and jasmonic acid) derived hormones together with enhanced xanthophyll content influenced biomass partitioning and abiotic stress tolerance (high light, salt, and drought), and it caused an up to 77% fruit yield increase and enhanced fruit's provitamin A content. In addition, metabolic and hormonal changes led to accumulation of key primary metabolites (e.g. osmoprotectants and antiaging agents) contributing with enhanced abiotic stress tolerance and fruit shelf life. Our findings pave the way for developing a new generation of crops that combine high productivity and increased nutritional value with the capability to cope with climate change-related environmental challenges.
  • Underestimated PAH accumulation potential of blue carbon vegetation: Evidence from sedimentary records of saltmarsh and mangrove in Yueqing Bay, China.

    Huang, Runqiu; Zhang, Chunfang; Xu, Xiangrong; Jin, Runjie; Li, Dan; Christakos, George; Xiao, Xi; He, Junyu; Agusti, Susana; Duarte, Carlos M.; Wu, Jiaping (The Science of the total environment, Elsevier BV, 2022-01-13) [Article]
    Sediments of blue carbon vegetation are becoming a sink of natural and anthropogenic pollutants, such as polycyclic aromatic hydrocarbons (PAHs). However, the extent to which PAHs are accumulated and varied in blue carbon sediments, and the impact of blue carbon vegetation on the accumulation and retention capacity of PAHs, have been poorly explored. This study examines the sedimentary records of PAHs in profiles from mangrove plantations, saltmarsh, and mudflat in Ximen Island and Maoyan Island of Yueqing Bay, China. The existence of blue carbon vegetation provides a sheltered environment for the accelerated burial of sediment and OC. Decadal PAH sedimentation records show staged changes characterized by the emission of PAHs and colonization of blue carbon vegetation, reflecting the accelerated burial of PAHs in sediments by blue carbon vegetation colonization. In addition, the colonization of blue carbon vegetation contributes to the shift of PAH compositions in sediments. This study provides new insights into the underestimated PAH accumulation potential and retention capacity of blue carbon vegetation and the corresponding underlying sediments, supporting the environmental benefits of blue carbon vegetation.
  • Signatures of selection underpinning rapid coral adaptation to the world’s warmest reefs

    Smith, E. G.; Hazzouri, Khaled M.; Choi, Jae Young; Delaney, Patrice; Al-Kharafi, Mohammed; Howells, Emily J.; Aranda, Manuel; Burt, John A. (Science Advances, American Association for the Advancement of Science (AAAS), 2022-01-12) [Article]
    Coral populations in the world’s warmest reefs, the Persian/Arabian Gulf (PAG), represent an ideal model system to understand the evolutionary response of coral populations to past and present environmental change and to identify genomic loci that contribute to elevated thermal tolerance. Here, we use population genomics of the brain coral Platygyra daedalea to show that corals in the PAG represent a distinct subpopulation that was established during the Holocene marine transgression, and identify selective sweeps in their genomes associated with thermal adaptation. We demonstrate the presence of positive and disruptive selection and provide evidence for selection of differentially methylated haplotypes. While demographic analyses suggest limited potential for genetic rescue of neighboring Indian Ocean reefs, the presence of putative targets of selection in corals outside of the PAG offers hope that loci associated with thermal tolerance may be present in the standing genetic variation.
  • Rice domestication.

    Fornasiero, Alice; Wing, Rod Anthony; Ronald, Pamela (Current biology : CB, Elsevier BV, 2022-01-11) [Article]
    Rice is a staple food crop for more than one-third of the global population (http://www.sustainablerice.org/), of which 90% live at or near the poverty line. Thus, rice genetic improvement is important for global food security and is critical for enhancing socioeconomic benefits and reducing the environmental impacts of agriculture. In continued efforts to address the long-standing problem of food security and sustainable agriculture, scientists are utilizing genes from diverse varieties of rice to improve the resilience of rice to pests, diseases and environmental stress. This Primer describes the history of rice domestication, the importance of wild relatives of rice for crop improvement, and the domestication of wild species of rice not previously planted by farmers - a new approach called neodomestication.
  • In Vitro and In Silico Approaches for the Evaluation of Antimicrobial Activity, Time-Kill Kinetics, and Anti-Biofilm Potential of Thymoquinone (2-Methyl-5-propan-2-ylcyclohexa-2,5-diene-1,4-dione) against Selected Human Pathogens

    Qureshi, Kamal A.; Imtiaz, Mahrukh; Parvez, Adil; Rai, Pankaj K.; Jaremko, Mariusz; Emwas, Abdul-Hamid M.; Bholay, Avinash D.; Fatmi, Muhammad Qaiser (Antibiotics, MDPI AG, 2022-01-10) [Article]
    Thymoquinone (2-methyl-5-propan-2-ylcyclohexa-2,5-diene-1,4-dione; TQ), a principal bioactive phytoconstituent of Nigella sativa essential oil, has been reported to have high antimicrobial potential. Thus, the current study evaluated TQ’s antimicrobial potential against a range of selected human pathogens using in vitro assays, including time-kill kinetics and anti-biofilm activity. In silico molecular docking of TQ against several antimicrobial target proteins and a detailed intermolecular interaction analysis was performed, including binding energies and docking feasibility. Of the tested bacteria and fungi, S. epidermidis ATCC 12228 and Candida albicans ATCC 10231 were the most susceptible to TQ, with 50.3 ± 0.3 mm and 21.1 ± 0.1 mm zones of inhibition, respectively. Minimum inhibitory concentration (MIC) values of TQ are in the range of 12.5–50 µg/mL, while minimum biocidal concentration (MBC) values are in the range of 25–100 µg/mL against the tested organisms. Time-kill kinetics of TQ revealed that the killing time for the tested bacteria is in the range of 1–6 h with the MBC of TQ. Anti-biofilm activity results demonstrate that the minimum biofilm inhibitory concentration (MBIC) values of TQ are in the range of 25–50 µg/mL, while the minimum biofilm eradication concentration (MBEC) values are in the range of 25–100 µg/mL, for the tested bacteria. In silico molecular docking studies revealed four preferred antibacterial and antifungal target proteins for TQ: D-alanyl-D-alanine synthetase (Ddl) from Thermus thermophilus, transcriptional regulator qacR from Staphylococcus aureus, N-myristoyltransferase from Candida albicans, and NADPH-dependent D-xylose reductase from Candida tenuis. In contrast, the nitroreductase family protein from Bacillus cereus and spore coat polysaccharide biosynthesis protein from Bacillus subtilis and UDP-N-acetylglucosamine pyrophosphorylase from Aspergillus fumigatus are the least preferred antibacterial and antifungal target proteins for TQ, respectively. Molecular dynamics (MD) simulations revealed that TQ could bind to all four target proteins, with Ddl and NADPH-dependent D-xylose reductase being the most efficient. Our findings corroborate TQ’s high antimicrobial potential, suggesting it may be a promising drug candidate for multi-drug resistant (MDR) pathogens, notably Gram-positive bacteria and Candida albicans.
  • Digital E. coli Counter: A Microfluidics and Computer Vision-Based DNAzyme Method for the Isolation and Specific Detection of E. coli from Water Samples

    Rauf, Sakandar; Tashkandi, Nouran Abdulatif; De Oliveira Filho, José Ilton; Oviedo-Osornio, Claudia Iluhí; Danish, Muhammad S.; Hong, Pei-Ying; Salama, Khaled N. (Biosensors, MDPI AG, 2022-01-10) [Article]
    Biological water contamination detection-based assays are essential to test water quality; however, these assays are prone to false-positive results and inaccuracies, are time-consuming, and use complicated procedures to test large water samples. Herein, we show a simple detection and counting method for E. coli in the water samples involving a combination of DNAzyme sensor, microfluidics, and computer vision strategies. We first isolated E. coli into individual droplets containing a DNAzyme mixture using droplet microfluidics. Upon bacterial cell lysis by heating, the DNAzyme mixture reacted with a particular substrate present in the crude intracellular material (CIM) of E. coli. This event triggers the dissociation of the fluorophore-quencher pair present in the DNAzyme mixture leading to a fluorescence signal, indicating the presence of E. coli in the droplets. We developed an algorithm using computer vision to analyze the fluorescent droplets containing E. coli in the presence of non-fluorescent droplets. The algorithm can detect and count fluorescent droplets representing the number of E. coli present in the sample. Finally, we show that the developed method is highly specific to detect and count E. coli in the presence of other bacteria present in the water sample.
  • Porous Ti3C2Tx MXene Membranes for Highly Efficient Salinity Gradient Energy Harvesting

    Hong, Seunghyun; El Demellawi, Jehad K.; Lei, Yongjiu; Liu, Zhixiong; Marzooqi, Faisal Al; Arafat, Hassan A.; Alshareef, Husam N. (ACS Nano, American Chemical Society (ACS), 2022-01-09) [Article]
    Extracting osmotic energy through nanoporous membranes is an efficient way to harvest renewable and sustainable energy using the salinity gradient between seawater and river water. Despite recent advances of nanopore-based membranes, which have revitalized the prospect of blue energy, their energy conversion is hampered by nanomembrane issues such as high internal resistance or low selectivity. Herein, we report a lamellar-structured membrane made of nanoporous Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> MXene sheets, exhibiting simultaneous enhancement in permeability and ion selectivity beyond their inherent trade-off. The perforated nanopores formed by facile H<sub>2</sub>SO<sub>4</sub> oxidation of the sheets act as a network of cation channels that interconnects interplanar nanocapillaries throughout the lamellar membrane. The constructed internal nanopores lower the energy barrier for cation passage, thereby boosting the preferential ion diffusion across the membrane. A maximum output power density of the nanoporous Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> MXene membranes reaches up to 17.5 W·m<sup>-2</sup> under a 100-fold KCl gradient at neutral pH and room temperature, which is as high as by 38% compared to that of the pristine membrane. The membrane design strategy employing the nanoporous two-dimensional sheets provides a promising approach for ion exchange, osmotic energy extraction, and other nanofluidic applications.
  • Controlling the hydraulic resistance of membrane biofilms by engineering biofilm physical structure.

    Desmond, Peter; Huisman, Kees Theo; Sanawar, Huma; Farhat, Nadia; Traber, Jacqueline; Fridjonsson, Einar O; Johns, Michael L; Flemming, Hans-Curt; Picioreanu, Cristian; Vrouwenvelder, Johannes S. (Water research, Elsevier BV, 2022-01-08) [Article]
    The application of membrane technology for water treatment and reuse is hampered by the development of a microbial biofilm. Biofilm growth in micro-and ultrafiltration (MF/UF) membrane modules, on both the membrane surface and feed spacer, can form a secondary membrane and exert resistance to permeation and crossflow, increasing energy demand and decreasing permeate quantity and quality. In recent years, exhaustive efforts were made to understand the chemical, structural and hydraulic characteristics of membrane biofilms. In this review, we critically assess which specific structural features of membrane biofilms exert resistance to forced water passage in MF/UF membranes systems applied to water and wastewater treatment, and how biofilm physical structure can be engineered by process operation to impose less hydraulic resistance ("below-the-pain threshold"). Counter-intuitively, biofilms with greater thickness do not always cause a higher hydraulic resistance than thinner biofilms. Dense biofilms, however, had consistently higher hydraulic resistances compared to less dense biofilms. The mechanism by which density exerts hydraulic resistance is reported in the literature to be dependant on the biofilms' internal packing structure and EPS chemical composition (e.g., porosity, polymer concentration). Current reports of internal porosity in membrane biofilms are not supported by adequate experimental evidence or by a reliable methodology, limiting a unified understanding of biofilm internal structure. Identifying the dependency of hydraulic resistance on biofilm density invites efforts to control the hydraulic resistance of membrane biofilms by engineering internal biofilm structure. Regulation of biofilm internal structure is possible by alteration of key determinants such as feed water nutrient composition/concentration, hydraulic shear stress and resistance and can engineer biofilm structural development to decrease density and therein hydraulic resistance. Future efforts should seek to determine the extent to which the concept of "biofilm engineering" can be extended to other biofilm parameters such as mechanical stability and the implication for biofilm control/removal in engineered water systems (e.g., pipelines and/or, cooling towers) susceptible to biofouling.
  • Structure and Functional Capacity of a Benzene-mineralizing, Nitrate-reducing Microbial Community

    Eziuzor, Samuel C.; Corrêa, Felipe Borim; Peng, Shuchan; Schultz, Junia; Kleinsteuber, Sabine; da Rocha, Ulisses Nunes; Adrian, Lorenz; Vogt, Carsten (Journal of Applied Microbiology, Wiley, 2022-01-07) [Article]
    <h4>Aims</h4>How benzene is metabolized by microbes under anoxic conditions is not fully understood. Here, we studied the degradation pathways in a benzene-mineralizing, nitrate-reducing enrichment culture.<h4>Methods and results</h4>Benzene mineralization was dependent on the presence of nitrate and correlated to enrichment of a Peptococcaceae phylotype only distantly related to known anaerobic benzene degraders of this family. Its relative abundance decreased after benzene mineralization had terminated, while other abundant taxa - Ignavibacteriaceae, Rhodanobacteraceae and Brocadiaceae - slightly increased. Generally, the microbial community remained diverse despite amendment of benzene as single organic carbon source, suggesting complex trophic interactions between different functional groups. A subunit of the putative anaerobic benzene carboxylase (AbcA) previously detected in Peptococcaceae was identified by metaproteomic analysis suggesting that benzene was activated by carboxylation. Detection of proteins involved in anaerobic ammonium oxidation (anammox) indicates that benzene mineralization was accompanied by anammox, facilitated by nitrite accumulation and the presence of ammonium in the growth medium.<h4>Conclusions</h4>The results suggest that benzene was activated by carboxylation and further assimilated by a novel Peptococcaceae phylotype.<h4>Significance and impact of the study</h4>The results confirm the hypothesis that Peptococcaceae are important anaerobic benzene degraders.
  • Paenibacillus piscarius sp. nov., a novel nitrogen-fixing species isolated from the gut of the armored catfish Parotocinclus maculicauda.

    da Silva, Mariana Barbalho Farias; Lemos, Ericka Arregue; Vollú, Renata E; Abreu, Fernanda; Rosado, Alexandre S.; Seldin, Lucy (Antonie van Leeuwenhoek, Springer Science and Business Media LLC, 2022-01-07) [Article]
    A Gram-positive, nitrogen-fixing and endospore-forming strain, designated P121T, was isolated from the gut of the armored catfish (Parotocinclus maculicauda) and identified as a member of the genus Paenibacillus based on the sequences of the 16S rRNA encoding gene, rpoB, gyrB and nifH genes and phenotypic analyses. The most closely related species to strain P121T were Paenibacillus rhizoplanae DSM 103993T, Paenibacillus silagei DSM 101953T and Paenibacillus borealis DSM 13188T, with similarity values of 98.9, 98.3 and 97.6%, respectively, based on 16S rRNA gene sequences. Genome sequencing revealed a genome size of 7,513,698 bp, DNA G + C content of 53.9 mol% and the presence of the structural nitrogenase encoding genes (nifK, nifD and nifH) and of other nif genes necessary for nitrogen fixation. Digital DNA-DNA hybridization (dDDH) experiments and average nucleotide identity (ANI) analyses between strain P121T and the type strains of the closest species demonstrated that the highest values were below the thresholds of 70% dDDH (42.3% with P. borealis) and 95% ANI (84.28% with P. silagei) for bacterial species delineation, indicating that strain P121T represents a distinct species. Its major cellular fatty acid was anteiso-C15:0 (42.4%), and the major isoprenoid quinone was MK-7. Based on physiological, genomic, biochemical and chemotaxonomic characteristics, we propose that strain P121T represents a novel species for which the name Paenibacillus piscarius sp. nov. is proposed (type strain = DSM 25072 = LFB-Fiocruz 1636).
  • Applied phenomics and genomics for improving barley yellow dwarf resistance in winter wheat

    Silva, Paula; Evers, Byron; Kieffaber, Alexandria; Wang, Xu; Brown, Richard; Gao, Liangliang; Fritz, Allan K.; Crain, Jared; Poland, Jesse (Cold Spring Harbor Laboratory, 2022-01-06) [Preprint]
    Barley yellow dwarf (BYD) is one of the major viral diseases of cereals. Phenotyping BYD in wheat is extremely challenging due to similarities to other biotic and abiotic stresses. Breeding for resistance is additionally challenging as the wheat primary germplasm pool lacks genetic resistance, with most of the few resistance genes named to date originating from a wild relative species. The objectives of this study were to, i) evaluate the use of high-throughput phenotyping (HTP) from unmanned aerial systems to improve BYD assessment and selection, ii) identify genomic regions associated with BYD resistance, and iii) evaluate genomic prediction models ability to predict BYD resistance. Up to 107 wheat lines were phenotyped during each of five field seasons under both insecticide treated and untreated plots. Across all seasons, BYD severity was lower with the insecticide treatment and plant height (PTHTM) and grain yield (GY) showed increased values relative to untreated entries. Only 9.2% of the lines were positive for the presence of the translocated segment carrying resistance gene $\textit{Bdv2}$ on chromosome 7DL. Despite the low frequency, this region was identified through association mapping. Furthermore, we mapped a potentially novel genomic region for resistance on chromosome 5AS. Given the variable heritability of the trait (0.211 0.806), we obtained relatively good predictive ability for BYD severity ranging between 0.06 0.26. Including $\textit{Bdv2}$ on the predictive model had a large effect for predicting BYD but almost no effect for PTHTM and GY. This study was the first attempt to characterize BYD using field-HTP and apply GS to predict the disease severity. These methods have the potential to improve BYD characterization and identifying new sources of resistance will be crucial for delivering BYD resistant germplasm.
  • Food-chain length determines the level of phenanthrene bioaccumulation in corals.

    Ashok, Ananya; Høj, Lone; Brinkman, Diane L; Negri, Andrew P; Agusti, Susana (Environmental pollution (Barking, Essex : 1987), Elsevier BV, 2022-01-06) [Article]
    Exposure from the dissolved-phase and through food-chains contributes to bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in organisms such as fishes and copepods. However, very few studies have investigated the accumulation of PAHs in corals. Information on dietary uptake contribution to PAHs accumulation in corals is especially limited. Here, we used Cavity-Ring-Down Spectroscopy (CRDS) to investigate the uptake rates and accumulation of a 13C-labeled PAH, phenanthrene, in Acropora millepora corals over 14 days. Our experiment involved three treatments representing exposure levels of increasing food-chain length. In Level W, corals were exposed to 13C-phenanthrene directly dissolved in seawater. In Level 1 representing herbivory, Dunaliella salina microalgal culture pre-exposed to 13C-phenanthrene for 48 h was added to the coral treatment jars. In Level 2 representing predation, corals were provided a diet of copepod (Parvocalanus crassirostris) nauplii fed on D. salina pre-exposed to 13C-phenanthrene. Bioconcentration factors (BCF) and bioaccumulation factors (BAF) were calculated as appropriate for all organisms, and biomagnification factors (BMF) were calculated for A. millepora. We found that while phenanthrene uptake rates were not significantly different for the treatments, the accumulated concentration in corals was significantly higher in Level W (33.5 ± 2.83 mg kg−1) than in Level 1 (27.55 ± 2.77 mg kg−1) and Level 2 (29.36 ± 3.84 mg kg−1). Coral log BAF values increased with food-chain length; Level 2 log BAF (6.45) was higher than Level W log BCF (4.18) and Level 1 log BAF (4.5). Coral BMF was also higher for Level 2 than for Level 1. Exposure to dissolved or diet-bound phenanthrene had no significant effect on the coral symbionts’ photosynthetic efficiency (Fv/Fm) as monitored by pulse-amplitude-modulation (PAM) fluorometry, indicating the PAH can be accumulated without toxic effects to their Photosystem II. Our study highlights the critical role of dietary exposure for pollutant accumulation in corals.
  • 14 GHz Schottky Diodes using a p -Doped Organic Polymer

    Loganathan, Kalaivanan; Scaccabarozzi, Alberto D.; Faber, Hendrik; Ferrari, Federico; Bizak, Zhanibek; Yengel, Emre; Naphade, Dipti R.; Gedda, Murali; He, Qiao; Solomeshch, Olga; Adilbekova, Begimai; Yarali, Emre; Tsetseris, Leonidas; Salama, Khaled N.; Heeney, Martin; Tessler, Nir; Anthopoulos, Thomas D. (Advanced Materials, Wiley, 2022-01-06) [Article]
    The low carrier mobility of organic semiconductors and the high parasitic resistance and capacitance often encountered in conventional organic Schottky diodes, hinder their deployment in emerging radio frequency (RF) electronics. Here we overcome these limitations by combining self-aligned asymmetric nanogap electrodes (∼25 nm) produced by adhesion-lithography, with a high mobility organic semiconductor and demonstrate RF Schottky diodes able to operate in the 5G frequency spectrum. We used C<sub>16</sub> IDT-BT, as the high hole mobility polymer, and studied the impact of p-doping on the diode performance. Pristine C<sub>16</sub> IDT-BT-based diodes exhibit maximum intrinsic and extrinsic cutoff frequencies (f<sub>C</sub> ) of >100 and 6 GHz, respectively. This extraordinary performance is attributed primarily to the planar nature of the nanogap channel and the diode's small junction capacitance (< 2 pF). Doping of C<sub>16</sub> IDT-BT with the molecular p-dopant C<sub>60</sub> F<sub>48</sub> , improves the diode's performance further by reducing the series resistance resulting to intrinsic and extrinsic f<sub>C</sub> of >100 and ∼14 GHz respectively, while the DC output voltage of a RF rectifier circuit increases by a tenfold. Our work highlights the importance of the planar nanogap architecture and paves the way for the use of organic Schottky diodes in large-area radio frequency electronics of the future. This article is protected by copyright. All rights reserved.
  • Ultrahigh-flux Nanoporous Graphene Membrane for Sustainable Seawater Desalination Using Low-grade Heat

    Lu, Dongwei; Zhou, Zongyao; Wang, Zhihong; Ho, Duc Tam; Sheng, Guan; Chen, Long; Zhao, Yumeng; Li, Xiang; Cao, Li; Schwingenschlögl, Udo; Ma, Jun; Lai, Zhiping (Advanced Materials, Wiley, 2022-01-06) [Article]
    Membrane distillation has attracted great attention in the development of sustainable desalination and zero-discharge processes because of its possibility to recover 100% water and the potential to integrate with low-grade heat such as solar energy. However, the conventional membrane structures and materials afford limited flux thus obstructing its practical application. Here we report ultrathin nanoporous graphene membranes by selectively forming thin graphene layers on the top edges of highly porous anodic alumina oxide support, which creates short and fast transport pathways for water vapor but not liquid. The process avoids the challenging pore-generation and substrate-transfer processes required to prepare regular graphene membranes. In the direct contact membrane distillation mode under a mild temperature pair of 65°C /25°C, the nanoporous graphene membranes show an average water flux of 421.7 Lm<sup>-2</sup> h<sup>-1</sup> with over 99.8% salt rejection, which is an order of magnitude higher than any reported polymeric membranes. The mechanism for high water flux is revealed by detailed characterizations and theoretical modeling. Outdoor field tests using Red Sea water heated under direct sunlight radiation show that the membranes have an average water flux of 86.3 Lm<sup>-2</sup> h<sup>-1</sup> from 8 am. to 8 pm., showing a great potential for real applications in seawater desalination. This article is protected by copyright. All rights reserved.
  • Synthesis and Organization of Gold-Peptide Nanoparticles for Catalytic Activities

    Abbas, Manzar; Susapto, Hepi Hari; Hauser, Charlotte (ACS Omega, American Chemical Society (ACS), 2022-01-06) [Article]
    A significant development in the synthesis strategies of metal-peptide composites and their applications in biomedical and bio-catalysis has been reported. However, the random aggregation of gold nanoparticles provides the opportunity to find alternative fabrication strategies of gold-peptide composite nanomaterials. In this study, we used a facile strategy to synthesize the gold nanoparticles via a green and simple approach where they show self-alignment on the assembled nanofibers of ultrashort oligopeptides as a composite material. A photochemical reduction method is used, which does not require any external chemical reagents for the reduction of gold ions, and resultantly makes the gold nanoparticles of size ca. 5 nm under mild UV light exposure. The specific arrangement of gold nanoparticles on the peptide nanofibers may indicate the electrostatic interactions of two components and the interactions with the amino group of the peptide building block. Furthermore, the gold-peptide nanoparticle composites show the ability as a catalyst to degradation of environmental pollutant p-nitrophenol to p-aminophenol, and the reaction rate constant for catalysis is calculated as 0.057 min–1 at a 50-fold dilute sample of 2 mg/mL and 0.72 mM gold concentration in the composites. This colloidal strategy would help researchers to fabricate the metalized bioorganic composites for various biomedical and bio-catalysis applications.
  • Unconventional metabolites in chromatin regulation

    Gapa, Liubov; Alfardus, Huda; Fischle, Wolfgang (Bioscience Reports, Portland Press Ltd., 2022-01-06) [Article]
    Chromatin, the complex of DNA and histone proteins, serves as a main integrator of cellular signals. Increasing evidence links cellular functional to chromatin state. Indeed, different metabolites are emerging as modulators of chromatin function and structure. Alterations in chromatin state are decisive for regulating all aspects of genome function and ultimately have the potential to produce phenotypic changes. Several metabolites such as acetyl-CoA, S-adenosyl methionine (SAM) or adenosine triphosphate (ATP) have now been well characterized as main substrates or cofactors of chromatin modifying enzymes. However, there are other metabolites that can directly interact with chromatin influencing its state or that modulate the properties of chromatin regulatory factors. Also, there is a growing list of atypical enzymatic and non-enzymatic chromatin modifications that originate from different cellular pathways that have not been in the limelight of chromatin research. Here, we summarize different properties and functions of uncommon regulatory molecules originating from intermediate metabolism of lipids, carbohydrates and amino acids. Based on the various modes of action on chromatin and the plethora of putative, so far not described chromatin regulating metabolites, we propose that there are more links between cellular functional state and chromatin regulation to be discovered. We hypothesize that these connections could provide interesting starting points for interfering with cellular epigenetic states at a molecular level.
  • Destabilization of the Bacterial Interactome Identifies Nutrient Restriction-Induced Dysbiosis in Insect Guts

    Marasco, Ramona; Fusi, Marco; Callegari, Matteo; Jucker, Costanza; Mapelli, Francesca; Borin, Sara; Savoldelli, Sara; Daffonchio, Daniele; Crotti, Elena (Microbiology Spectrum, American Society for Microbiology, 2022-01-05) [Article]
    Changes in diet play a role in reshaping the gut microbiome in animals, inducing dysbiotic configurations of the associated microbiome. Although studies have reported on the effects of specific nutrient contents on the diet, studies regarding the conditions altering the microbiome configurations and networking in response to diet changes are limited.
  • Contrasting Effects of Local Environmental and Biogeographic Factors on the Composition and Structure of Bacterial Communities in Arid Monospecific Mangrove Soils

    Thomson, Timothy; Fusi, Marco; Bennett-Smith, Morgan; Prinz, N.; Aylagas, Eva; Carvalho, Susana; Lovelock, Catherine E; Jones, Burton; Ellis, Joanne (Microbiology Spectrum, American Society for Microbiology, 2022-01-05) [Article]
    Mangrove ecosystems are increasingly being recognized for their potential to sequester atmospheric carbon, thereby mitigating the effects of anthropogenically driven greenhouse gas emissions. The bacterial community in the soils plays an important role in the breakdown and recycling of carbon and other nutrients.

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