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Polyhydroxyalkanoates (PHAs) are regarded as alternatives to petroleum-based plastics and can be produced through marine bacteria that have adapted to high-salt and low-temperature conditions. In this study, Halomonassp. YLGW01 was used to produce PHAs using volatile fatty acids as carbon sources, and its utilization ability and optimization were investigated by a response surface methodology. The results showed that the strain has high utilization abilities for growth and PHA accumulation using lactate and acetate, and use of a combination of these volatile fatty acids (VFAs) showed a synergistic effect on PHA production. Finally, a fed-batch culture based on the optimized VFAs achieved 12.3 g/L of dried cell weight (DCW) and 6.6 g/L of PHAs, which are similar to the results of 10.2 g/L of DCW and 6.3 g/L of PHAs from applying food-waste water. Overall, the feasibility of Halomonassp. YLGW01 as a PHA-producing strain with VFAs was demonstrated.

Polyimide/hexagonal boron nitride (PI/BN) composite films have attracted interest as heat dissipation materials for advanced microelectronic devices. However, conventional preparations of PI/BN composite films employ harmful and expensive high-boiling organic solvents. In this work, thermally conductive PI/BN composite films were, for the first time, prepared using a nontoxic, eco-friendly, and inexpensive aqueous solvent. BN was ultrasonically exfoliated in a mixed solvent of water and tert-butanol to obtain aqueous BN suspensions, in which a poly(amic acid) salt (PAAS) was synthesized. The PAAS/BN suspensions were then drop-casted, and thermally imidized into PI/BN composite films. The PI/BN films exhibited excellent in-plane and out-of-plane thermal conductivities (up to 15.043 W/mK and 1.142 W/mK, respectively), which is attributed to the effective exfoliation and dispersion of BN in the aqueous solvent. Furthermore, these films exhibited high tensile strength, flexibility, and thermal stability.

AbstractThe velvetregulators VosA and VelB are primarily involved in spore maturation and dormancy. Previous studies found that the VosA-VelB hetero-complex coordinates certain target genes that are related to fungal differentiation and conidial maturation in Aspergillus nidulans. Here, we characterized the VosA/VelB-inhibited developmental gene vidDin A. nidulans. Phenotypic analyses demonstrated that the vidDdeleted mutant exhibited defect fungal growth, a reduced number of conidia, and delayed formation of sexual fruiting bodies. The deletion of vidDdecreased the amount of conidial trehalose, increased the sensitivity against heat stress, and reduced the conidial viability. Moreover, the absence of vidDresulted in increased production of sterigmatocystin. Together, these results show that VidD is required for proper fungal growth, development, and sterigmatocystin production in A. nidulans.

AbstractSpecies of the genus Aspergillushave a variety of effects on humans and have been considered industrial cell factories due to their prominent ability for manufacturing several products such as heterologous proteins, secondary metabolites, and organic acids. Scientists are trying to improve fungal strains and re-design metabolic processes through advanced genetic manipulation techniques and gene delivery systems to enhance their industrial efficiency and utility. In this review, we describe the current status of the genetic manipulation techniques and transformation methods for species of the genus Aspergillus. The host strains, selective markers, and experimental materials required for the genetic manipulation and fungal transformation are described in detail. Furthermore, the advantages and disadvantages of these techniques are described.

Catalytic amine regeneration can decrease the energy required for regeneration; therefore, high economic and energy efficiency can be expected for CO2capture. These factors necessitate the development of an inexpensive and easily synthesizable catalyst that can exhibit a high desorption efficiency. When selecting a catalyst, its physicochemical properties must be considered, because they markedly affect the chemical reaction between CO2–amine–catalyst. In this study, mesoporous silica SBA-15, particularly, rod-type SBA-15, wrinkled SBA-15 (modified from rod-type SBA-15), and NiO-impregnated rod-type and wrinkled SBA-15 catalysts were investigated in terms of the CO2desorption rate and heat duty in a CO2–rich 5M monoethanolamine (MEA) solution at 86 ℃. The physicochemical properties of the catalysts were compared to investigate their effect on the CO2desorption efficiency. The performance of wrinkled SBA-15 impregnated with 10wt% NiO in a CO2–rich MEA solution was optimal, exhibiting a 12% higher CO2desorption rate and 19.9% lower heat duty than the MEA solution without a catalyst. Furthermore, the stability and reproducibility of the catalysts were confirmed through repeated experiments under identical conditions. Based on the experimental results and analysis, a plausible desorption mechanism for CO2–MEA–catalyst was proposed. It is expected that the regeneration heat duty during the CO2regeneration can be effectively reduced by a catalyst, eventually applied to the CO2capture.

AbstractMonA is a subunit of a guanine nucleotide exchange factor that is important for vacuole passing and autophagy processes in eukaryotes. In this study, we characterized the function of MonA, an orthologue of Saccharomyces cerevisiaeMon1, in the model fungus Aspergillus nidulansand a toxigenic fungus A. flavus. In A. nidulans, the absence of AnimonAled to decreased fungal growth, reduced asexual reproduction, and defective cleistothecia production. In addition, AnimonAdeletion mutants exhibited decreased spore viability, had reduced trehalose contents in conidia, and were sensitive to thermal stress. In A. flavus, deletion of AflmonAcaused decreased fungal growth and defective production of asexual spores and sclerotia structures. Moreover, the absence of monAaffected vacuole morphology in both species. Taken together, these results indicate that MonA plays conserved roles in controlling fungal growth, development and vacuole morphology in A. nidulansand A. flavus.

For electrodes in electrochemical double-layer capacitors, carbon nanofibers (CNFs) were prepared by thermal treatment of precursor polymer nanofibers, fabricated by electrospinning. Poly(acrylonitrile-co-vinylimidazole) (PAV) was employed as a precursor polymer of carbon nanofibers due to the effective cyclization of PAV polymer chains during thermal treatment compared to a typical precursor, polyacrylonitrile (PAN). PAV solutions with different comonomer compositions were prepared and electrospun to produce precursor nanofibers. Surface images obtained from scanning electron microscopy showed that their nanofibrous structure was well preserved after carbonization. It was also confirmed that electrospun PAV nanofibers were successfully converted to carbon nanofibers after the carbonization step by Raman spectroscopy. Carbon nanofiber electrodes derived from PAV showed higher specific capacitances and energy/power densities than those from PAN, which was tested by coin-type cells. It was also shown that PAV with an acrylonitrile/vinylimidazole composition of 83:17 is most promising for the carbon nanofiber precursor exhibiting a specific capacitance of 114 F/g. Their energy and power density are 70.1 Wh/kg at 1 A/g and 9.5 W/kg at 6 A/g, respectively. In addition, pouch cells were assembled to load the higher amount of electrode materials in the cells, and a box-like cyclic voltammetry was obtained with high capacitances.

Sulfur mustard gas, also called HD, is one of the main chemical warfare agents and has claimed thousands of lives and left many more contaminated. The development of functional materials to promptly capture and detoxify sulfur mustard within a few minutes is extremely important to save the lives of the affected people. This has motivated us to explore excellent detoxification systems that can be deployed in the field to rapidly capture and hydrolyze mustard gas in a short time. To that end, we present a silver-ion-exchanged zeolite Y [(Ag+)n@Y, n= 5, 13, 21, 32, 43, and 55] that can rapidly capture mustard gas and its simulant (2-chloroethyl ethyl sulfide, CEES) in ambient conditions to enable the prompt hydrolysis of the CEES captured in its nanopores. The capture and hydrolysis ability of Ag+@Y positively correlated with its number of Ag+ions. In addition, 70% of CEES (2.5 μL in 1 mL) was captured by (Ag+)55@Y within 20 min at 25 °C in ambient conditions. Moreover, 100% CEES (2.5 μL in 1 mL aqueous ethanol cosolvent) was hydrolyzed in 1 min at 25 °C. The efficiency of Ag+@Y in capturing and hydrolyzing CEES as well as mustard gas is thus a system with high detoxification efficiency for this dangerous chemical warfare agent.

AbstractMon1 is a guanine nucleotide exchange factor subunit that activates the Ypt7 Rab GTPase and is essential for vacuole trafficking and autophagy in eukaryotic organisms. Here, we identified and characterized the function of Mon1, an ortholog of Saccharomyces cerevisiaeMon1, in a human fungal pathogen, Cryptococcus neoformans. Mutation in mon1resulted in hypersensitivity to thermal stress. The mon1deletion mutant exhibited increased sensitivity to cell wall and endoplasmic reticulum stress. However, the mon1deletion mutant showed more resistance to the antifungal agent fluconazole. In vivostudies demonstrated that compared to the wild-type strain, the mon1deletion mutant attenuated virulence in the Galleria mellonellainsect model. Moreover, the mon1deletion mutant was avirulent in the murine inhalation model. These results demonstrate that Mon1 plays a crucial role in stress survival and pathogenicity in C. neoformans.

ABSTRACTLittle is known about the modulatory capacity of the microbiota in early intestinal development. We examined various intestinal models that respond to gut microbial metabolites based on human pluripotent stem cell-derived human intestinal organoids (hIOs): physiologically relevant in vitrofetal-like intestine, intestinal stem cell, and intestinal disease models. We found that a newly isolated Limosilactobacillus reuteristrain DS0384 accelerated maturation of the fetal intestine using 3D hIO with immature fetal characteristics. Comparative metabolomic profiling analysis revealed that the secreted metabolite N-carbamyl glutamic acid (NCG) is involved in the beneficial effect of DS0384 cell-free supernatants on the intestinal maturation of hIOs. Experiments in an intestinal stem cell spheroid model and hIO-based intestinal inflamed model revealed that the cell-free supernatant from DS0384 comprising NCG promoted intestinal stem cell proliferation and was important for intestinal protection against cytokine-induced intestinal epithelial injury. The probiotic properties of DS0384 were also evaluated, including acid and bile tolerance and ability to adhere to human intestinal cells. Seven-day oral administration of DS0384 and cell-free supernatant promoted the intestinal development of newborn mice. Moreover, NCG exerted a protective effect on experimental colitis in mice. These results suggest that DS0384 is a useful agent for probiotic applications and therapeutic treatment for disorders of early gut development and for preventing intestinal barrier dysfunction.

Filamentous fungi produce a vast number of asexual spores that act as efficient propagules. Due to their infectious and/or allergenic nature, fungal spores affect our daily life. Aspergillusspecies produce asexual spores called conidia; their formation involves morphological development and metabolic changes, and the associated regulatory systems are coordinated by multiple transcription factors (TFs).