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The sclerotia of Wolfiporia hoelen are one of the most important traditional Chinese medicines and foods commonly used in China, Japan, Korea, and other Asian countries. To provide a high-quality reference genome and deepen our understanding of the genome of W. hoelen to elucidate various biological phenomena. In this study, we assembled three genomes of W. hoelen using a combination of Nanopore and Illumina sequencing strategies. The fifteen-chromosome genome L7 of W. hoelen was assembled with two-sided telomere and rDNA sequences for the first time. The chromosome count was subsequently confirmed through collinearity analysis, correcting the previous belief that W. hoelen had only fourteen chromosomes. Moreover, the aneuploid genome was discovered in W. hoelen for the first time through sequencing depth analysis of different chromosomes, and only some strains of W. hoelen exhibit aneuploid genomes. According to the genome analysis of homokaryotic offspring and protoplast-isolated strains, a potential variation in chromosome allocation patterns was revealed. Moreover, the gene function enrichment analysis of genes on reduplicated chromosomes demonstrated that aneuploidy in the genome may be the result of environmental adaptation for W. hoelen. The discovery of an aneuploid genome also provides new ideas for genetic improvement of W. hoelen.
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Aneuploidia , Cromossomos Fúngicos/genética , Genoma Fúngico , Medicina Tradicional Chinesa , Hypocreales/genética , Sequenciamento de Nucleotídeos em Larga Escala , Adaptação Fisiológica/genéticaRESUMO
Sclerotia of Wolfiporia hoelen are one of the most important traditional Chinese medicines and are commonly used in China, Japan, Korea, and other Asian countries. In the present study, we presented the first high-quality homokaryotic genome of W. hoelen with 14 chromosomes which was evaluated with assembly index, telomere position detection, and whole-genome collinearity. A 64.44 Mb genome was assembled with a Contig N50 length of 3.76 Mb. The imbalanced distribution of transposons and chromosome characters revealed the probable two-speed genome of W. hoelen. High consistency between methylation and transposon conserved the genome stability. The expansion of the gene family about signal transduction and nutritional transport has intimate relationships with sclerotial formation. Up-regulation of expression for distinctive decomposition enzymes, ROS clearance genes, biosynthesis of unsaturated fatty acids, and change of the cell wall components maintained high-speed growth of mycelia that may be the high-temperature adaption strategy of W. hoelen. Further, the analysis of mating-control genes demonstrated that HD3 probably had no function on mating recognition, with the HD protein in a distant genetic with known species. Overall, the high-quality genome of W. hoelen provided crucial information for genome structure and stability, high-temperature adaption, and sexual and asexual process.
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Wolfiporia , Ácidos Graxos Insaturados/metabolismo , Genoma , Filogenia , Espécies Reativas de Oxigênio/metabolismo , Temperatura , Wolfiporia/químicaRESUMO
Compared to the current mainstream rigid covalent organic frameworks (COFs) linked by imine bonds, flexible COFs have certain advantages of elasticity and self-adaptability, but their construction and application are greatly limited by the complexity in synthesis and difficulty in obtaining regular structure. Herein, we reported for the first time a series of flexible amine-linked COFs with high crystallinity synthesized by formic acid with unique catalytic and reductive bifunctional properties, rather than acetic acid, the most common catalyst for COF synthesis. The reaction mechanism was demonstrated to be a synchronous in situ reduction during the formation of imine bond. The flexibilities of the products endow them with accommodative adaptability to guest molecules, thus increasing the adsorption capacities for nitrogen and iodine by 27 % and 22 %, respectively. Impressively, a novel concept of flexibilization degree was proposed firstly, which provides an effective approach to rationally measure the flexibility of COFs.
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We report the first example of 2D covalent organic framework nanosheets (Redox-COF1) for the selective reduction and inâ situ loading of valence-variable, redox-sensitive and long-lived radionuclides (abbreviated as VRL nuclides). Compared with sorbents based on chemical adsorption and physical adsorption, the redox adsorption mechanism of Redox-COF1 can effectively reduce the impact of functional group protonation under the usual high-acidity conditions in chemisorption, and raise the adsorption efficiency from the monotonous capture by pores in physisorption. The adsorption selectivity for UO2 2+ reaches up to unprecedented ca. 97 % at pHâ 3, more than for any analogous adsorbing material.
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Constructing three-dimensional (3D) structural characteristics on two-dimensional (2D) covalent organic frameworks (COFs) is a good approach to effectively improve the permeability and mass transfer rate of the materials and realize the rapid adsorption for guest molecules, while avoiding the high cost and monomer scarcity in preparing 3D COFs. Herein, we report for the first time a series of colyliform crystalline 2D COFs with quasi-three-dimensional (Q-3D) topologies, consisting of unique "stereoscopic" triangular pores, large interlayer spacings and flexible constitutional units which makes the pores elastic and self-adaptable for the guest transmission. The as-prepared QTD-COFs have a faster adsorption rate (2.51â g h-1 ) for iodine than traditional 2D COFs, with an unprecedented maximum adsorption capacity of 6.29â g g-1 . The excellent adsorption performance, as well as the prominent irradiation stability allow the QTD-COFs to be applied for the rapid removal of radioactive iodine.
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In numerous reports on selective solid-phase extraction (SPE) of uranium, the extraction of uranium is generally accepted as a direct coordination of the ligands on the solid matrix with the uranyl, in which the critical effect of the hydration shell on the uranyl is neglected. The related mechanism in the extraction process remains unclear. Herein, the detailed calculation of activation energy and the geometry of the identified transition states reveal that the uranium extraction by a newly-synthesized urea-functionalized graphite oxide (Urea-GO) is in essence an exchange process between the ligands on Urea-GO and the coordinated water molecules in the first hydration shell of the uranyl. Moreover, we demonstrate that it is the ketone oxygen in the urea ligand to displace the coordinated water molecule of uranyl due to its stronger bonding ability and lower steric-hindrance, whereas the nitrogen atom in the same ligand is proved to be an electron donor that enables the oxygen atom to have stronger affinity for uranium through electron delocalization effects evaluated on the basis of calculations of the second-order interaction energy between donor and acceptor orbitals. We therefore propose a new ligand-exchange mechanism for the SPE process. This study advances the fundamental understanding of uranium extraction, and provides theoretical and practical guidance on ligand design for selective complexation of uranium(VI) and other metal ions in aqueous solution. Finally, the effect of nitrate ions on the extraction of uranyl was successfully explained based on the experimental and theoretical study.
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Light-triggered drug delivery based on near-infrared (NIR)-mediated photothermal nanocarriers has received tremendous attention for the construction of cooperative therapeutic systems in nanomedicine. Herein, a new paradigm of light-responsive drug carrier that doubles as a photothermal agent is reported based on the NIR light-absorber, Rb(x) WO3 (rubidium tungsten bronze, Rb-TB) nanorods. With doxorubicin (DOX) payload, the DOX-loaded Rb-TB composite (Rb-TB-DOX) simultaneously provides a burst-like drug release and intense heating effect upon 808-nm NIR light exposure. MTT assays show the photothermally enhanced antitumor activity of Rb-TB-DOX to the MCF-7 cancer cells. Most remarkably, Rb-TB-DOX combined with NIR irradiation also shows dramatically enhanced chemotherapeutic effect to DOX-resistant MCF-7 cells compared with free DOX, demonstrating the enhanced efficacy of combinational chemo-photothermal therapy for potentially overcoming drug resistance in cancer chemotherapy. Furthermore, in vivo study of combined chemo-photothermal therapy is also conducted and realized on pancreatic (Pance-1) tumor-bearing nude mice. Apart from its promise for cancer therapy, the as-prepared Rb-TB can also be employed as a new dual-modal contrast agent for photoacoustic tomography and (PAT) X-ray computed tomography (CT) imaging because of its high NIR optical absorption capability and strong X-ray attenuation ability, respectively. The results presented in the current study suggest promise of the multifunctional Rb(x)WO3 nanorods for applications in cancer theranostics.
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Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Nanotubos , Técnicas Fotoacústicas , Fototerapia , Rubídio/química , Tomografia Computadorizada por Raios X , Tungstênio/química , Humanos , Raios Infravermelhos , Células MCF-7RESUMO
The present theoretical study provides a realistic evaluation of the equilibrium structure, reaction modes, and bonding characteristics of a variety of neptunyl complexes formed with bis(triazinyl) N-donor extractants, which differ in their bridging groups such as pyridine, bipyridines, and orthophenanthroline, corresponding to the ligands (L) of tridentate bis(triazinyl)pyridines and tetradentate bis(triazinyl)bipyridines and bis(triazinyl)-1,10-phenanthrolines (BTPhens), respectively. Our calculations show that coordination of [NpO2](+) to tetradentate ligands is more favorable than that to tridentate ones no matter in a gas, aqueous, or organic phase. The presence of nitrate ions can enhance the coordination ability of neptunyl and stabilize the neutral NpO2L(NO3) complexes in thermodynamics. Our studies indicate that the complexation reaction mode [NpO2(H2O)n](+) + L + NO3(-) â NpO2L(NO3) + nH2O is the most probable at the interface between water and the organic phase. The contribution of an orthophenanthroline bridging group is relatively more pronounced compared to its pyridine counterpart in ligand-exchange reaction. Complexation reactions of hydrated neptunyl with C2-BTPhen and BTPhen assisted by a nitrate ion are favorable thermodynamically, resulting from the least deformation of the ligand and strong complexation stability. The quantum theory of atoms-in-molecules and charge decomposition analysis suggest that electron delocalization and charge transfer are the main reasons responsible for stabilization of the tetradentate complexes and reveal a strong ionic feature of the Np-ligand bonds. Inspection of the frontier molecular orbitals reveals a distinct 5f orbital (Np) interaction with ligand atoms, implying the extent of f-based covalency. Our study may facilitate the rational design of ligands toward the improvement of their binding ability with Np(V) and more efficient separation of Np in spent nuclear fuels.
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P. umbellatus sclerotium is a traditional Chinese medicine that is widely utilized in China, Korea, Japan, and other countries due to its diverse medicinal activities, such as diuretic, antitumor, anticancer, and immune system enhancement effects. Conidia, which are common asexual spores in various fungi, are not universally present in Polyporus species. In this study, the asexual life cycle of P. umbellatus was elucidated. Conidia, i.e. arthorconidia, were produced by both dikaryotic and monokaryotic strains. In the dikaryotic strain, binucleate, uninucleate, and nuclei-free conidia were identified with proportions of 67.9 %, 12.4 %, and 19.7 %, respectively. Conversely, the monokaryotic strain did not produce binucleate conidia. This discrepancy suggests that binucleate spores are heterokaryons, while uninucleate spores are homokaryons. Clamp connections were observed in dikaryotic hyphae, but were absent in monokaryotic hyphae. Monokaryotic strains were obtained from conidia of the dikaryotic strain. Additionally, mating types were determined through pairing tests, and successful crossbreeding occurred between monokaryotic strains derived from conidia and basidiospores from different strains. This study introduced the first crossbreeding strategy for P. umbellatus.
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Polyporus , Esporos Fúngicos , Esporos Fúngicos/crescimento & desenvolvimento , Polyporus/crescimento & desenvolvimento , Polyporus/metabolismo , Núcleo Celular , Reprodução Assexuada , Hifas/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Genes Fúngicos Tipo AcasalamentoRESUMO
Upconverting nanoparticles (UCNPs) have attracted considerable attention as potential photosensitizer carriers for photodynamic therapy (PDT) in deep tissues. In this work, a new and efficient NIR photosensitizing nanoplatform for PDT based on red-emitting UCNPs is designed. The red emission band matches well with the efficient absorption bands of the widely used commercially available photosensitizers (Ps), benefiting the fluorescence resonance energy transfer (FRET) from UCNPs to the attached photosensitizers and thus efficiently activating them to generate cytotoxic singlet oxygen. Three commonly used photosensitizers, including chlorine e6 (Ce6), zinc phthalocyanine (ZnPc) and methylene blue (MB), are loaded onto the alpha-cyclodextrin-modified UCNPs to form Ps@UCNPs complexes that efficiently produce singlet oxygen to kill cancer cells under 980 nm near-infrared excitation. Moreover, two different kinds of drugs are co-loaded onto these nanoparticles: chemotherapy drug doxorubicin and PDT agent Ce6. The combinational therapy based on doxorubicin (DOX)-induced chemotherapy and Ce6-triggered PDT exhibits higher therapeutic efficacy relative to the individual means for cancer therapy in vitro.
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Nanopartículas/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Animais , Clorofilídeos , Transferência Ressonante de Energia de Fluorescência , Humanos , Indóis/química , Indóis/uso terapêutico , Isoindóis , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos , Nanopartículas/uso terapêutico , Compostos Organometálicos/química , Compostos Organometálicos/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química , Porfirinas/uso terapêutico , Ratos , Oxigênio Singlete/metabolismo , Compostos de Zinco , alfa-Ciclodextrinas/químicaRESUMO
In this report, we systematically studied the effects of different metal ions on the fluorescence of common thiolate ligand capped quantum dots. Generally, heavy metal ions exhibited much more significant fluorescence quenching. Also, the coordination capability and steric hindrance of the ligand jointly affect the quenching efficiency.
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Graphene has attracted great interest for its superior physical, chemical, mechanical, and electrical properties that enable a wide range of applications from electronics to nanoelectromechanical systems. Functionalization is among the significant vectors that drive graphene towards technological applications. While the physical properties of graphene have been at the center of attention, we still lack the knowledge framework for targeted graphene functionalization. In this critical review, we describe some of the important chemical and physical processes for graphene functionalization. We also identify six major challenges in graphene research and give perspectives and practical strategies for both fundamental studies and applications of graphene (315 references).
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Grafite/química , Derivados de Benzeno/química , Eletrônica , Halogenação , Hidrogenação , Nanopartículas/química , Nanotecnologia , Polímeros/química , Silício/químicaRESUMO
Purification or separation of single-walled carbon nanotubes (SWCNTs) is one of the most fundamental steps before they are used for research and technological applications. Based on the difference of their physical and chemical properties, separation of carbon nanotubes (CNTs) can be categorized into three groups: length separation, metallic and semiconducting tubes separation and chirality separation. In this review, we first briefly review the purification of CNTs and then focus on the different methods for the separation of CNTs.
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A new amidoxime-functionalized carbonaceous sorbent has been successfully prepared using hydrothermal carbon microsphere as solid matrix and diaminomaleonitrile as precursor of amidoxime ligand. Effects of pH, sorbent dosage, contact time, temperature, initial U(VI) concentration and ionic strength on U(VI) sorption were investigated in detail through batch experiments. Sorption of U(VI) on the sorbent was pH-dependent. Sorption equilibrium was reached in 5 min. Distinctively, higher temperature was beneficial to the sorption of U(VI) in the range of 15-60 degrees C, high ionic strength up to 1 mol L(-1) NaNO3 had almost no effect on the sorption, and the maximum U(VI) sorption capacity of 466 mg g(-1) was observed under the conditions tested. The as-synthesized sorbent exhibited a high selectivity for U(VI) over other 12 competing ions coexisting in a simulated nuclear industrial effluent sample and the U(VI) sorption amount reached up to 1.09 mmol g(-1), accounting for about 52% of the total sorption amount.
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The sclerotia of Pachyma hoelen are one of the traditional Chinese medicines and foods that are widely used in East Asian countries. The strains used for cultivation showed bad performance in recent years, and breeding of superior strains has become increasingly important for this fungus. Nevertheless, the mating system and life cycle of P. hoelen were still ambiguous. In this study, the methods for distinguishing between homokaryotic offspring with different mating types were established, as well as confirmation of strain hybridization based on allelic polymorphism at a locus of the rpb2 gene. The bipolar mating system was confirmed according to the mating results of homokaryotic SSIs. The fact that heterokaryotic parents produce homokaryotic meiospores proves that the life cycle is heterothallic. Combining scanning electron microscope observation and DAPI (4',6-diamidino-2-phenylindole) fluorescent staining of hymenium and basidiospores in situ and ex situ, nuclear migration pattern from basidia to spores was revealed. The heterothallic life cycle was verified, revised, and supplemented step by step. This is the first report of systematic research on the mating system, life cycle, and outcrossing of homokaryotic offspring in P. hoelen. It will be helpful for the biological research, strain improvement, and development of the P. hoelen industry.
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Basidiomycota , Polyporales , Wolfiporia , Alelos , Animais , Basidiomycota/genética , Genes Fúngicos Tipo Acasalamento/genética , Estágios do Ciclo de Vida , Polyporales/genética , Esporos Fúngicos/genética , Wolfiporia/genéticaRESUMO
The sclerotia of Wolfiporia cocos are a kind of traditional medicine and food with excellent benefits and are widely used in China, Japan, and other Asian countries. The mating system of fungi is not only of practical importance for breeding but also has profound effects on genetic variability and molecular evolution. However, the lack of clamp connections in W. cocos increases the difficulty of research on mating systems. In this study, homokaryons and heterokaryons were distinguished by comparing the characteristics of culture, fruiting tests, and molecular markers, which was further demonstrated by k-mer analysis based on Illumina sequencing. Uninucleate, binucleate, and nuclei-free condition basidiospores of W. cocos were observed, and binucleate basidiospores were the most predominant. Brown-type colonies, slow growth rates in both PDA medium and sawdust substrate, and neutral pH after the growth of mycelia and unfruiting were found to be the morphological and growth characteristics of homokaryotic strains. Primers SSR37 and 38 were screened to identify homokaryons. K-mer analysis based on Illumina sequencing exhibited different heterozygous ratios for homokaryons and heterokaryons. The results revealed that pseudo-homothallism was the predominant mode of reproduction in the Chinese population of W. cocos, and heterothallism also existed in all probability. This study will be helpful for the cross-breeding of this precious medicinal mushroom and for understanding its evolution and population structure.
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The fungus "Fuling" has been used in Chinese traditional medicine for more than 2000 years, and its sclerotia have a wide range of biological activities including antitumour, immunomodulation, anti-inflammation, antioxidation, anti-aging etc. This prized medicinal mushroom also known as "Hoelen" is resurrected from a piece of pre-Linnean scientific literature. Fries treated it as Pachyma hoelen Fr. and mentioned that it was cultivated on pine trees in China. However, this name had been almost forgotten, and Poria cocos (syn. Wolfiporia cocos), originally described from North America, and known as "Tuckahoe" has been applied to "Fuling" in most publications. Although Merrill mentioned a 100 years ago that Asian Pachyma hoelen and North American P. cocos are similar but different, no comprehensive taxonomical studies have been carried out on the East Asian Pachyma hoelen and its related species. Based on phylogenetic analyses and morphological examination on both the sclerotia and the basidiocarps which are very seldomly developed, the East Asian samples of Pachyma hoelen including sclerotia, commercial strains for cultivation and fruiting bodies, nested in a strongly supported, homogeneous lineage which clearly separated from the lineages of North American Wolfiporia cocos and other species. So we confirm that the widely cultivated "Fuling" Pachyma hoelen in East Asia is not conspecific with the North American Wolfiporia cocos. Based on the changes in Art. 59 of the International Code of Nomenclature for algae, fungi, and plants, the generic name Pachyma, which was sanctioned by Fries, has nomenclatural priority (ICN, Art. F.3.1), and this name well represents the economically important stage of the generic type. So we propose to use Pachyma rather than Wolfiporia, and subsequently Pachyma hoelen and Pachyma cocos are the valid names for "Fuling" in East Asia and "Tuckahoe" in North America, respectively. In addition, a new combination, Pachyma pseudococos, is proposed. Furthermore, it seems that Pachyma cocos is a species complex, and that three species exist in North America.
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The preparation of subnanoporous covalent-organic-framework (COF) membranes with high performance for ion/molecule sieving still remains a great challenge. In addition to the difficulties in fabricating large-area COF membranes, the main reason is that the pore size of 2D COFs is much larger than that of most gas molecules and/or ions. It is urgently required to further narrow their pore sizes to meet different separation demands. Herein, we report a simple and scalable way to grow large-area, pliable, free-standing COF membranes via a one-step route at organic-organic interface. The pore sizes of the membranes can be adjusted from >1 nm to sub-nm scale by changing the stacking mode of COF layers from AA to AB stacking. The obtained AB stacking COF membrane composed of highly-ordered nanoflakes is demonstrated to have narrow aperture (â¼0.6 nm), uniform pore distribution and shows good potential in organic solvent nanofiltration, water treatment and gas separation.
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A crystalline quantum dot of a COF was prepared for the first time by the original BRB method and a novel pathway for online monitoring of the COF reaction rate was proposed. The quantum dot can respond to uranyl ion quickly and sensitively and is of great potential in uranium detection.
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The title compound, C25H25N9O9·C16H36N+·H2PO4 - (I) or (C25H25N9O9)·(n-Bu4N+)·(H2PO4 -) (systematic name: 3-(4-nitro-phen-yl)-1,1-bis-{2-[3-(4-nitro-phen-yl)ureido]eth-yl}urea tetra-butyl-ammonium di-hydrogen phosphate), comprises a tris-urea receptor (R), a di-hydrogen phosphate anion and a tetra-n-butyl-ammonium cation. It crystallizes with two independent formula units in the asymmetric unit. The conformations of the two tris-urea receptors are stabilized by N-Hâ¯O and C-Hâ¯O intra-molecular hydrogen bonds. Each di-hydrogen phosphate anion has two O-Hâ¯O inter-molecular hydrogen-bonding inter-actions with the other di-hydrogen phosphate anion. Inversion-related di-anion units are linked by further O-Hâ¯O hydrogen bonds, forming a chain propagating along the a-axis direction. Each di-hydrogen phosphate anion makes a total of four N-Hâ¯O(H2PO4 -) hydrogen bonds with two ureido subunits from two different tris-urea receptors, hence each tris-urea receptor provides the two ureido subunits for the encapsulation of the H2PO4 - hydrogen-bonded chain. There are numerous inter-molecular C-Hâ¯O hydrogen bonds present involving both receptor mol-ecules and the tetra-n-butyl-ammonium cations, so forming a supra-molecular three-dimensional structure. One of the butyl groups and one of the nitro groups are disordered over two positions of equal occupancy.