Role of water in the formation of low-temperature coal oxidation products: An experimental isotope tracer study.

The interaction between water and coal is of great significance to the study of coal spontaneous combustion (CSC) in humid mine environments. Here, using an isotope tracing method to trace oxygen atoms in water, the role of water in the formation of CO, CO2, product water, and other substances during CSC was quantitatively studied through thermogravimetry coupled with mass spectrometry (TG-MS). In addition, Pearson correlation analysis was used to evaluate the relationships between the amounts of CO and CO2 generated during CSC and the different functional groups. The migration and transformation paths of oxygen atoms in water were analyzed. The results showed that water participated in the CSC reaction to produce CO, CO2, and product water in a dynamic, temperature-dependent process. CO and CO2 were formed through different reaction paths involving reactions between water and aldehyde and carboxyl groups. Further, carboxyl groups were also involved in the reaction with coal to form product water. The results from this study are helpful for understanding the influence of water in each stage of CSC, thereby aiding in its prevention and control.

Genomic analysis of Colletotrichum camelliae responsible for tea brown blight disease.

BACKGROUND: Colletotrichum camelliae, one of the most important phytopathogenic fungi infecting tea plants (Camellia sinensis), causes brown blight disease resulting in significant economic losses in yield of some sensitive cultivated tea varieties. To better understand its phytopathogenic mechanism, the genetic information is worth being resolved. RESULTS: Here, a high-quality genomic sequence of C. camelliae (strain LT-3-1) was sequenced using PacBio RSII sequencing platform, one of the most advanced Three-generation sequencing platforms and assembled. The result showed that the fungal genomic sequence is 67.74 Mb in size (with the N50 contig 5.6 Mb in size) containing 14,849 putative genes, of which about 95.27% were annotated. The data revealed a large class of genomic clusters potentially related to fungal pathogenicity. Based on the Pathogen Host Interactions database, a total of 1698 genes (11.44% of the total ones) were annotated, containing 541 genes related to plant cell wall hydrolases which is remarkably higher than those of most species of Colletotrichum and others considered to be hemibiotrophic and necrotrophic fungi. It's likely that the increase in cell wall-degrading enzymes reflects a crucial adaptive characteristic for infecting tea plants. CONCLUSION: Considering that C. camelliae has a specific host range and unique morphological and biological traits that distinguish it from other species of the genus Colletotrichum, characterization of the fungal genome will improve our understanding of the fungus and its phytopathogenic mechanism as well.

Long-distance migration law of radon in overburden of abandoned goaf during coal spontaneous combustion.

The surface isotope radon measurement method (SIRMM) is widely used in fire source detection in abandoned mines. However, studies on the long-distance migration of radon during coal spontaneous combustion are lacking, which hinders the further popularization of this technology in coal fire prevention and control. For this reason, the migration law of radon in overlying strata in fire areas was studied through experiments and numerical simulation. The radon exhalation concentration of coal was found to increase at first and then decrease in the range of 30-350 °C through experiments. The radon concentration reaches the maximum value (557.1 Bq/m3) at 150 °C, which is 6.3 times higher than that at 30 °C. Based on the radon source term obtained by fitting the experimental data, the radon migration model of coal spontaneous combustion in abandoned goaf was constructed, and the dynamic distribution characteristics of the airflow, temperature, and radon concentration fields in the overlying strata area were analyzed. The internal relationship between surface radon and underground fire source was discussed. The simulation results revealed the sharp change in the porosity of the overlying rock causes radon concentration at the interface between the caving and fissure zones to increase continually with the process of spontaneous combustion, providing material and energy support for the long-distance radon migration. When the maximum temperature of the coal pile reaches 70 °C, the concentration of radon released from the coal pile increases rapidly to 13696 Bq/m3, and the radon from the underground space appears on the surface at this temperature. In the range of 70-150 °C, with rapid increase in radon released from coal piles, the surface concentration of radon also increased rapidly to 225 Bq/m3. At the high-temperature stage exceeding 150 °C, the concentration of radon released from coal piles exhibited a downward trend, resulting in a decrease in the rate of increase of radon concentration on the surface. A close relationship between the surface radon concentration and underground fire source temperature in the process of coal spontaneous combustion was observed. In the spatial position, the peak position of radon on the surface was highly consistent with that of the fire source longitudinally, which ensures the accuracy of the SIRMM to determine the location of the hidden fire source. This suggests that the SIRMM can accurately evaluate the fire source's temperature and fire area's development trend.

Novel Viroid-Like RNAs Naturally Infect a Filamentous Fungus.

To date, viroids have been found to naturally infect only plants, resulting in substantial losses for some crops. Whether viroids or viroid-like RNAs naturally infect non-plant hosts remains unknown. Here the existence of a set of exogenous, single-stranded circular RNAs, ranging in size from 157 to 450 nucleotides, isolated from the fungus Botryosphaeria dothidea and nominated B. dothidea RNAs (BdcRNAs) is reported. BdcRNAs replicate autonomously in the nucleus via a rolling-circle mechanism following a symmetric pathway. BdcRNA infection induces symptoms, because BdcRNAs can apparently modulate, to different degrees, specific biological traits (e.g., alter morphology, decrease growth rate, attenuate virulence, and increase or decrease tolerance to osmotic and oxidative stress) of the host fungus. Overall, BdcRNAs have genome characteristics similar to those of viroids and exhibit pathogenic effects on fungal hosts. It is proposed that these novel fungus infecting RNAs should be termed mycoviroids. BdcRNA(s) may be considered additional inhabitants at the frontier of life in terms of genomic complexity, and represent a new class of acellular entities endowed with regulatory functions, and novel epigenomic carriers of biological information.

A far-red light-inducible CRISPR-Cas12a platform for remote-controlled genome editing and gene activation.

The CRISPR-Cas12a has been harnessed as a powerful tool for manipulating targeted gene expression. The possibility to manipulate the activity of CRISPR-Cas12a with a more precise spatiotemporal resolution and deep tissue permeability will enable targeted genome engineering and deepen our understanding of the gene functions underlying complex cellular behaviors. However, currently available inducible CRISPR-Cas12a systems are limited by diffusion, cytotoxicity, and poor tissue permeability. Here, we developed a far-red light (FRL)­inducible CRISPR-Cas12a (FICA) system that can robustly induce gene editing in mammalian cells, and an FRL-inducible CRISPR-dCas12a (FIdCA) system based on the protein-tagging system SUperNova (SunTag) that can be used for gene activation under light-emitting diode­based FRL. Moreover, we show that the FIdCA system can be deployed to activate target genes in mouse livers. These results demonstrate that these systems developed here provide robust and efficient platforms for programmable genome manipulation in a noninvasive and spatiotemporal fashion.

A mycovirus modulates the endophytic and pathogenic traits of a plant associated fungus.

Fungi are generally thought to live in host plants with a single lifestyle, being parasitism, commensalism, or mutualism. The former, known as phytopathogenic fungi, cause various plant diseases that result in significant losses every year; while the latter, such as endophytic fungi, can confer fitness to the host plants. It is unclear whether biological factors can modulate the parasitic and mutualistic traits of a fungus. In this study, we isolated and characterized a mycovirus from an endophytic strain of the fungus Pestalotiopsis theae, a pathogen of tea (Camellia sinensis). Based on molecular analysis, we tentatively designated the mycovirus as Pestalotiopsis theae chrysovirus-1 (PtCV1), a novel member of the family Chrysoviridae, genus Alphachrysovirus. PtCV1 has four double-stranded (ds) RNAs as its genome, ranging from 0.9 to 3.4 kbp in size, encapsidated in isometric particles. PtCV1 significantly reduced the growth rates of its host fungus in vitro (ANOVA; P-value < 0.001) and abolished its virulence in planta (ANOVA; P-value < 0.001), converting its host fungus to a non-pathogenic endophyte on tea leaves, while PtCV1-free isolates were highly virulent. Moreover, the presence of PtCV1 conferred high resistance to the host plants against the virulent P. theae strains. Here we report a mycovirus that modulates endophytic and phytopathogenic fungal traits and provides an alternative approach to biological control of plant diseases caused by fungi.

A versatile genetic control system in mammalian cells and mice responsive to clinically licensed sodium ferulate.

Dynamically adjustable gene- and cell-based therapies are recognized as next-generation medicine. However, the translation of precision therapies into clinics is limited by lack of specific switches controlled by inducers that are safe and ready for clinical use. Ferulic acid (FA) is a phytochemical with a wide range of therapeutic effects, and its salt sodium ferulate (SF) is used as an antithrombotic drug in clinics. Here, we describe an FA/SF-adjustable transcriptional switch controlled by the clinically licensed drug SF. We demonstrated that SF-responsive switches can be engineered to control CRISPR-Cas9 systems for on-command genome/epigenome engineering. In addition, we integrated FA-controlled switches into programmable biocomputers to process logic operations. We further demonstrated the dose-dependent SF-inducible transgene expression in mice by oral administration of SF tablets. Engineered switches responsive to small-molecule clinically licensed drugs to achieve adjustable transgene expression profiles provide new opportunities for dynamic interventions in gene- and cell-based precision medicine.

A green tea-triggered genetic control system for treating diabetes in mice and monkeys.

Cell-based therapies are recognized as the next frontier in medicine, but the translation of many promising technologies into the clinic is currently limited by a lack of remote-control inducers that are safe and can be tightly regulated. Here, we developed therapeutically active engineered cells regulated by a control system that is responsive to protocatechuic acid (PCA), a metabolite found in green tea. We constructed multiple genetic control technologies that could toggle a PCA-responsive ON/OFF switch based on a transcriptional repressor from Streptomyces coelicolor We demonstrated that PCA-controlled switches can be used for guide RNA expression-mediated control of the CRISPR-Cas9 systems for gene editing and epigenetic remodeling. We showed how these technologies could be used as implantable biocomputers in live mice to perform complex logic computations that integrated signals from multiple food metabolites. Last, we used our system to treat type 1 and type 2 diabetes in mice and cynomolgus monkeys. This biocompatible and versatile food phenolic acid-controlled transgenic device opens opportunities for dynamic interventions in gene- and cell-based precision medicine.

Genomic, Morphological and Biological Traits of the Viruses Infecting Major Fruit Trees.

Banana trees, citrus fruit trees, pome fruit trees, grapevines, mango trees, and stone fruit trees are major fruit trees cultured worldwide and correspond to nearly 90% of the global production of woody fruit trees. In light of the above, the present manuscript summarizes the viruses that infect the major fruit trees, including their taxonomy and morphology, and highlights selected viruses that significantly affect fruit production, including their genomic and biological features. The results showed that a total of 163 viruses, belonging to 45 genera classified into 23 families have been reported to infect the major woody fruit trees. It is clear that there is higher accumulation of viruses in grapevine (80/163) compared to the other fruit trees (each corresponding to less than 35/163), while only one virus species has been reported infecting mango. Most of the viruses (over 70%) infecting woody fruit trees are positive-sense single-stranded RNA (+ssRNA), and the remainder belong to the -ssRNA, ssRNA-RT, dsRNA, ssDNA and dsDNA-RT groups (each corresponding to less than 8%). Most of the viruses are icosahedral or isometric (79/163), and their diameter ranges from 16 to 80 nm with the majority being 25-30 nm. Cross-infection has occurred in a high frequency among pome and stone fruit trees, whereas no or little cross-infection has occurred among banana, citrus and grapevine. The viruses infecting woody fruit trees are mostly transmitted by vegetative propagation, grafting, and root grafting in orchards and are usually vectored by mealybug, soft scale, aphids, mites or thrips. These viruses cause adverse effects in their fruit tree hosts, inducing a wide range of symptoms and significant damage, such as reduced yield, quality, vigor and longevity.

Cobalt- and Nickel-Containing Germanotungstates Based on Open Wells-Dawson Structure: Synthesis and Characterization of Tetrameric Anion.

Two transition-metal-substituted compounds K10H10{[Co(H2O)2]2[Co(H2O)3]2(Ge4W36O130)}·32H2O (1Co) and K10H10{[Ni(H2O)2]2[Ni(H2O)3]2(Ge4W36O130)}·32H2O (2Ni), have been successfully synthesized, both of which consist of the S-shaped tetrameric structure {Ge4W36} constructed from trivacant Keggin-type germanotungstate precursor K8Na2[ A-α-GeW9O34]·25H2O. These compounds were characterized by single crystal X-ray diffraction crystallography, X-ray powder diffraction (XRD), Raman spectra, thermogravimetric analysis (TGA), electrochemistry, and IR spectra. In addition, the UV spectra and the electrospray-ionization mass spectra (ESI-MS) were employed to investigated the stable pH value range of 1Co and 2Ni in aqueous solution.

Engineering Mammalian Designer Cells for the Treatment of Metabolic Diseases.

Synthetic biology applies engineering principles to biological systems and has significantly advanced the design of synthetic gene circuits that can reprogram cell activities to perform new functions. The ability to engineer mammalian designer cells with robust therapeutic behaviors has brought new opportunities for treating metabolic diseases. In this review, the authors highlight the most recent advances in the development of synthetic designer cells uploaded with open- or closed-loop gene circuits for the treatment of metabolic disorders including diabetes, hypertension, hyperuricemia, and obesity, and discuss the current technologies and future perspectives in applying these designer cells for clinical applications. In the future, more and more rationally designed cells will be constructed and revolutionized to treat a number of metabolic disorders in an intelligent manner.

An {As4 Cu4 [Cu(H2 O)]12 } Cluster Incorporated within Four [Nb7 O22 ]9- Units.

A gigantic 16-copper-containing 28-niobate cluster, Na14 K7 H5 {As4 Cu4 [Cu(H2 O)]12 Nb28 O109 }⋅37.5 H2 O (1), has been prepared by a one-pot reaction, which is the first example of arsenic copper clusters containing polyoxoniobate, and the first tetrahedral arrangement of both the Cu cluster and the [Nb7 O22 ]9- subunits.

A dsRNA virus with filamentous viral particles.

Viruses with double-stranded RNA genomes form isometric particles or are capsidless. Here we report a double-stranded RNA virus, Colletotrichum camelliae filamentous virus 1 (CcFV-1) isolated from a fungal pathogen, that forms filamentous particles. CcFV-1 has eight genomic double-stranded RNAs, ranging from 990 to 2444 bp, encoding 10 putative open reading frames, of which open reading frame 1 encodes an RNA-dependent RNA polymerase and open reading frame 4 a capsid protein. When inoculated, the naked CcFV-1 double-stranded RNAs are infectious and induce the accumulation of the filamentous particles in vivo. CcFV-1 is phylogenetically related to Aspergillus fumigatus tetramycovirus-1 and Beauveria bassiana polymycovirus-1, but differs in morphology and in the number of genomic components. CcFV-1 might be an intermediate virus related to truly capsidated viruses, or might represent a distinct encapsidating strategy. In terms of genome and particle architecture, our findings are a significant addition to the knowledge of the virosphere diversity.Viruses with double-stranded RNA (dsRNA) genomes form typically isometric particles or are capsid-less. Here, the authors identify a mycovirus with an eight-segmented dsRNA genome that forms exceptionally long filamentous particles and could represent an evolutionary link between ssRNA and dsRNA viruses.