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Mitochondria are essential organelles for maintaining intracellular homeostasis. Their dysfunction can directly or indirectly affect cell functioning and is linked to multiple diseases. Donation of exogenous mitochondria is potentially a viable therapeutic strategy. For this, selecting appropriate donors of exogenous mitochondria is critical. We previously demonstrated that ultra-purified bone marrow-derived mesenchymal stem cells (RECs) have better stem cell properties and homogeneity than conventionally cultured bone marrow-derived mesenchymal stem cells. Here, we explored the effect of contact and noncontact systems on three possible mitochondrial transfer mechanisms involving tunneling nanotubes, connexin 43 (Cx43)-mediated gap junction channels (GJCs), and extracellular vesicles (Evs). We show that Evs and Cx43-GJCs provide the main mechanism for mitochondrial transfer from RECs. Through these two critical mitochondrial transfer pathways, RECs could transfer a greater number of mitochondria into mitochondria-deficient (ρ0) cells and could significantly restore mitochondrial functional parameters. Furthermore, we analyzed the effect of exosomes (EXO) on the rate of mitochondrial transfer from RECs and recovery of mitochondrial function. REC-derived EXO appeared to promote mitochondrial transfer and slightly improve the recovery of mtDNA content and oxidative phosphorylation in ρ0 cells. Thus, ultrapure, homogenous, and safe stem cell RECs could provide a potential therapeutic tool for diseases associated with mitochondrial dysfunction.

Herein, we report the synthesis and planar chiral properties of a pair of water-soluble cationic pillar[5]arenes with stereogenic carbons. Interestingly, although units of the molecules were rotatable, only one planar chiral diastereomer existed in water in both cases. As a new type of chiral source, these molecules transmitted chiral information from the planar chiral cavities to the assembly of a water-soluble extended π-conjugated compound, affording circularly polarized luminescence (CPL). The chirality transfer process and resulting CPL were extremely sensitive to the feed ratio of the chiral pillar[5]arenes owing to the combined action of their planar chirality, bulkiness, and strong binding properties. When a limited amount of chiral source was added, further assembly of the extended π-conjugated compound into helical fibers with CPL was triggered. Unexpectedly, larger amounts of chiral source destroyed the helical fiber assemblies, resulting in elimination of the chirality and CPL properties from the assembled structures.

[4.3.3]Propellane fused with π-conjugated units is efficiently synthesized and functionalized in a naphthalene-selective manner to yield a chiroptical derivative.

A series of culture media for haloarchaea were evaluated to optimize the production of ultrahigh-molecular-weight (UHMW) poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) by Haloferax mediterranei. Cells of H. mediterranei grew (> 1 g/L of dry cell weight) and accumulated PHBV upon flask cultivation in 10 medium types with neutral pH and NaCl concentration > 100 g/L. Molecular weight and compositional analysis revealed that the number-average molecular weight (Mn) of PHBV produced with six selected types of media ranged from 0.8 to 3.5 × 106 g/mol and the 3-hydroxyvalerate (3HV) composition ranged from 8 to 36 mol%. Cultivation in two NBRC media, 1214 and 1380, resulted in the production of PHBV with an Mn of more than 3.0 × 106 g/mol and a weight-average molecular weight of more than 5.0 × 106 g/mol, indicating the production of UHMW-PHBV. These culture media contained small amount of complex nutrients like yeast extract and casamino acids, suggesting that H. mediterranei likely produced UHMW-PHBV on poor nutrient condition. Haloferax mediterranei grown in NBRC medium 1380 produced PHBV with the highest 3HV composition. A solvent-cast film of UHMW-PHBV with 26.4 mol% 3HV produced from 1-L flask cultivation with NBRC medium 1380 was found to be flexible and semi-transparent. Thermal analysis of the UHMW-PHBV cast film revealed melting and glass-transition temperatures of 90.5 °C and − 2.7 °C, respectively. • Haloarchaeal culture media were evaluated to produce UHMW-PHBV by H. mediterranei. • UHMW-PHBV with varied molecular weight was produced dependent on culture media. • Semi-transparent film could be made from UHMW-PHBV with 26.4 mol% 3HV.

Gas fermentation is one of the promising bioprocesses to convert CO2 or syngas to important chemicals. Thermophilic gas fermentation of volatile chemicals has the potential for the development of consolidated bioprocesses that can simultaneously separate products during fermentation. This study reports the production of acetone from CO2 and H2, CO, or syngas by introducing the acetone production pathway using acetyl–coenzyme A (Ac-CoA) and acetate produced via the Wood–Ljungdahl pathway in Moorella thermoacetica. Reducing the carbon flux from Ac-CoA to acetate through genetic engineering successfully enhanced acetone productivity, which varied on the basis of the gas composition. The highest acetone productivity was obtained with CO–H2, while autotrophic growth collapsed with CO2–H2. By adding H2 to CO, the acetone productivity from the same amount of carbon source increased compared to CO gas only, and the maximum specific acetone production rate also increased from 0.04 to 0.09 g-acetone/g-dry cell/h. Our development of the engineered thermophilic acetogen M. thermoacetica, which grows at a temperature higher than the boiling point of acetone (58°C), would pave the way for developing a consolidated process with simplified and cost-effective recovery via condensation following gas fermentation.

Reversible multielectron-transfer materials are of considerable interest because of the potential impact to advance present electrochemical energy storage technology by boosting energy density. To date, a few oxide-based materials can reach an electron-transfer number per metal-cation (e

Coordination polymers represent a suitable model to study redox mechanisms in materials where both metal cation and ligand undergo electrochemical reactions and are capable to proceed through rever...

The discharge of industrial dyes and their breakdown products are often environmentally harmful. Here, we describe a biodegradation method using Burkholderia multivorans CCA53, which exhibits a capacity to degrade azo dyes, particularly ethyl red. Under the optimized culture conditions, 100 μM ethyl red was degraded more than 99% after incubation for 8 h. Real-time PCR analysis of azoR1 and azoR2, encoding two azoreductases, revealed that transcription level of these genes is enhanced at early phase under the optimized conditions. For a more practical approach, hydrolysates were prepared from eucalyptus or Japanese cedar chips or rice straw, and rice straw hydrolysate was used as the best medium for ethyl red biodegradation. Under those conditions, ethyl red was also degraded with high efficiency (>91%). We have thus constructed a potentially economical method for the biodegradation of ethyl red.

We developed a color changeable aromatic vapor detection system by combining the mechanochromism and vapochromism of pillar[6]arene containing one benzoquinone unit. The color of pillar[6]arene solid was changed by mechanochromism before vapor exposure. Different aromatic vapors then induced an obvious vapochromic color change from dark red to light orange or vice versa.

The basidiomycetous yeast Ustilago shanxiensis CBS 10075, which was isolated from a wilting leaf in China, produces mannosylerythritol lipid (MEL) biosurfactants. Here, we report the draft genome sequence of U. shanxiensis CBS 10075, which was 21.7 Mbp in size, with a GC content of 52.55%, comprising 65 scaffolds.

We designed the triad molecule, bis‐o‐carborane‐substituted bis(thienylethynyl)benzene, as a filler for realizing thermochromic luminescent behaviors based on conventional polymer films, such as polystyrene. From the optical measurements, it was found that the triad can show solid‐state emission and dual‐luminescent properties with variable intensity ratios depending on media. From the mechanistic studies including the experiments with the methyl‐substituted model compound, it was revealed that dual emission should be originated from the locally excited and twisted intramolecular charge transfer states, and the latter emission band is significantly enhanced in the solid states. We prepared amorphous films containing variable concentrations of the triad with the spin‐coating method and investigated optical properties. It was found that intensity ratios were drastically changed by altering the concentration of the triad. By increasing the proportion of the triad, aggregation occurred, and emission color was apparently varied through the changes in intensity ratios of the dual emission property. Based on the aggregation‐induced luminochromic property of the triad, thermochromic luminescence was finally realized by heating the amorphous films. The rational design for obtaining thermochromic luminescent amorphous films is illustrated in this paper.

Construction of acid-tolerant strains of Saccharomyces cerevisiae is required for various bioproduction processes. We previously isolated the gene IoGAS1 from multiple stress-tolerant Issatchenkia orientalis as a gene conferring sulfuric acid resistance in S. cerevisiae, but its acid tolerance was only investigated using sulfuric acid. Here, we evaluated the growth and ethanol fermentation ability of the IoGAS1-expressing S. cerevisiae strain, B4-IoGAS1, by using various acidic reagents. B4-IoGAS1 exhibited faster growth than the control strain, B4-CON, when cultured aerobically with sulfuric, hydrochloric, formic, acetic, and lactic acids at pH below 2.4. However, the growth of B4-IoGAS1 was suppressed at pH above 2.48, irrespective of the type of acid reagents. Furthermore, B4-IoGAS1 exhibited higher performance of ethanol fermentation than B4-CON under 250 mM lactic acid condition at pH 2.37. These results demonstrate that IoGAS1 could facilitate the aerobic growth and anaerobic ethanol production under different acidic stressed conditions.

Platinadithiolene nanosheet synthesized by interfacial transmetallation is a possible candidate of a 2D topological insulator at room temperature and an effective catalyst for the electrochemical HER., The construction of two-dimensional metal complex materials is fascinating because of the structural and functional diversity of these materials. Previously, we have reported the synthesis of electroconductive nickelladithiolene (NiDT) and palladadithiolene (PdDT) nanosheets using benzenehexathiol (BHT). Down the group from Ni, Pd to Pt, there is a distinct positive shift in the reduction potential; as a result, it becomes synthetically more challenging to stabilize Pt2+ than to form metallic Pt(0) in the presence of BHT as a reducing agent. Herein, a novel synthetic strategy for the preparation of platinadithiolene nanosheet (PtDT) using a dibutyltin-protected BHT ligand is reported, leading to transmetallation in the presence of dioxygen. Both free-standing stacked sheets and atomic layer sheets were obtained and characterized by microscopic techniques such as AFM, SEM, and TEM. To study the morphology of the sheets and determine their charge neutrality, X-ray photoelectron (XP) and infrared (IR) spectroscopic techniques were used. Powder X-ray diffraction analysis of the multilayer PtDT indicates a half-way slipped hexagonal configuration in the P3[combining macron]1m space group. The band structure of this PtDT exhibits a band gap at the Fermi level, which is different from that of NiDT in the staggered configuration, and a Dirac gap, indicating the possibility of 2D topological insulation at room temperature. PtDT is insulating but chemically activated by oxidation with I2 to increase the conductivity by more than 106 folds up to 0.39 S cm–1. The MDT sheets exhibit electrocatalytic activity for the hydrogen evolution reaction, and the activity order is NiDT < PdDT < PtDT.

Gas fermentation is a promising biological process for the conversion of CO2 or syngas into valuable chemicals. Homoacetogens are microorganisms growing autotrophically using CO2 and H2 or CO and metabolizing them to form acetate coupled with energy conservation. The challenge in the metabolic engineering of the homoacetogens is divergence of the acetate formation, whose intermediate is acetyl-CoA, to a targeted chemical with sufficient production of adenosine triphosphate (ATP). In this study, we report that an engineered strain of the thermophilic homoacetogen Moorella thermoacetica, in which a pool of acetyl-CoA is diverted to ethanol without ATP production, can maintain autotrophic growth on syngas. We estimated the ATP production in the engineered strains under different gaseous compositions by considering redox-balanced metabolism for ethanol and acetate formation. The culture test showed that the combination of retaining a level of acetate production and supplying the energy-rich CO allowed maintenance of the autotrophic growth during ethanol production. In contrast, autotrophy was collapsed by complete elimination of the acetate pathway or supplementation of H2-CO2. We showed that the intracellular level of ATP was significantly lowered on H2-CO2 in consistent with the incompetence. In the meantime, the complete disruption of the acetate pathway resulted in the redox imbalance to produce ethanol from CO, albeit a small loss in the ATP production. Thus, preservation of a fraction of acetate formation is required to maintain sufficient ATP and balanced redox in CO-containing gases for ethanol production.

Pyruvate, a potential precursor of various chemicals, is one of the fundamental chemicals produced by the fermentation process. We previously reported a pyruvate-producing Escherichia coli strain LAFCPCPt-accBC-aceE (PYR) that has the potential to be applied to the industrial production of pyruvate. In this study, the availability of the PYR strain for the production of pyruvate-derivative chemicals was evaluated using a d-lactate-producing strain (LAC) based on the PYR strain. The LAC strain expresses a d-lactate dehydrogenase-encoding gene from Lactobacillus bulgaricus under the control of a T7 expression system. The d-lactate productivity of the LAC strain was further improved by limiting aeration and changing the induction period for the expression of d-lactate dehydrogenase-encoding gene expression. Under combined conditions, the LAC strain produced d-lactate at 21.7 &plusmn, 1.4 g&middot, L&minus, 1, which was compatible with the pyruvate production by the PYR strain (26.1 &plusmn, 0.9 g&middot, 1). These results suggest that we have succeeded in the effective conversion of pyruvate to d-lactate in the LAC strain, demonstrating the wide versatility of the parental PYR strain as basal strain for various chemicals production.

Bis(diimino)metal coordination frameworks (MDI, M = transition metal), which are a class of metal organic frameworks with two-dimensional anisotropy, high electric conductivity, and redox activity, are attractive platforms for tailoring electrochemical properties by introducing a heterometallic composition. In this study, we synthesized heterometallic Co

Conformational control of aliphatic oligoketones bearing two 1,3-diketone subunits is achieved by molecular recognition with pillar[5]arene. Pillar[5]arene binds to aliphatic ketones, with association constants K of ∼10 M-1, to form pseudorotaxanes. The pseudorotaxanes are locked by BF2 complexation at the 1,3-diketone sites through quasi-solid-state reactions. X-ray crystallography reveals linear conformations for the axis molecules. The effect of supramolecular conformational restriction is evaluated using an alkyl-linked dyad chromophore system that shows solvatochromism upon intramolecular aggregation.

Coordination polymers represent a suitable model to study redox mechanisms in materials where both metal cation and ligand undergo electrochemical reactions and are capable to proceed through reversible multielectron-transfer processes with insertion of cation and anion into their open structures. Designing new coordination polymers for electrochemical energy storage with improved performance relays also on the understanding of their structure-properties relationship. Here, we present a family of copper-based coordination polymer with hexafunctionalized benzene ligands forming a kagome-type layered structure, where the in uence of the functional groups in their structure and electrochemical properties is investigated. Their chemical and structural properties have been explored by means of PXRD, and FTIR and Raman spectroscopies, followed by investigation of their electrochemical performance in Li half-cells by CV and galvanostatic cycling techniques. Ex-situ PXRD, Raman, XPS and ToF-SIMS measurements of cycled electrodes have been carried out providing insights into the redox mechanism of these copper-based coordination polymers as positive electrode materials.

The genus Geobacillus comprises gram-positive, moderate thermophilic, and aerobic or facultative anaerobic strains that can form endospores. The members of the genus are widely distributed in nature and have diverse habitats including cool environments. This is potentially due to not only their capacity for endospore formation but also their genetic plasticity that facilitates environmental adaptation, because Geobacillus spp. show remarkable genome diversification and have acquired beneficial properties that facilitate their exploitation of respective habitats. Such properties are often attractive for whole-cell applications performed at elevated temperatures. Consequently, extensive studies have been conducted to develop genetic tools for Geobacillus spp. and to generate their derivatives that are more practical for whole-cell applications. With the aim of highlighting the biotechnological platforms of Geobacillus spp., this chapter reviews genetic tools, notable properties, and biotechnological studies on Geobacillus spp. along with their history, habitats, and general characteristics. We also explore different perspectives from relevant studies.

Organic–inorganic hybrid thin films containing [Ti4(μ3-O)(OiPr)5(μ-OiPr)3(O3PPh)3]·THF (TiOPPh) were prepared via the hybridization of TiOPPh with poly(vinyl phenol) (PVP), poly(styrene-co-allyl alcohol) (PSA), and poly(bisphenol A-co-epichlorohydrin) (PBE) using spin coating. These thin films were characterized in terms of their transmittance, pencil hardness, and surface morphologies. The transmittance values of the PVP hybrid thin films decreased with the addition of TiOPPh because of the formation of Ti–O–Ph bonds. The pencil hardness values of the hybrid thin films were in the order PVP > PBE > PSA hybrids. Using confocal laser scanning microscopy and atomic force microscopy, the pencil hardness values were determined to be strongly dependent on the surface morphology, such as the roughness and presence of pin holes. The model cluster was synthesized by the reaction of TiOPPh with excess ethanol to study the structures of the TiOPPh in hybrids. From the nuclear magnetic resonance spectroscopy and single-crystal X-ray structure analyses, the main core structure of the model cluster was found to retain the core structure of TiOPPh. Organic–inorganic hybrid thin films containing [Ti4(μ3-O)(OiPr)5(μ-OiPr)3(O3PPh)3]·THF (TiOPPh) as element blocks were prepared via hybridization with the hydroxyl-substituted organic polymers (PVP, PSA, or PBE) by spin-coating. The hybrid thin films were characterized by AFM, DSC, and pencil hardness. The pencil hardness values of the PVP hybrid thin films were in the order 20 > 40 > 0 wt% and were dependent on the surface smoothness. When TiOPPh was reacted with excess ethanol, the core was retained. Therefore, the core of TiOPPh will be retained in the hybrid polymers.

A sensitive analytical method was developed for the simultaneous detection of 11 chiral pharmaceuticals and their hepatic metabolites by liquid chromatography-tandem mass spectrometry (LC-MS/MS) using an ovomucoid chiral column. After optimization of the LC conditions, all pharmaceuticals examined were enantio-separated with Rs of >0.82 in LC-MS/MS analysis. The limit of detections of all pharmaceuticals by MS/MS detection ranged from 1.2 to 92.3 nM, which is approximately 1000 - 25000 times lower than those obtained by UV detection. From hepatic metabolite analyses in P450-expressing cells, metabolites of three pharmaceuticals were detected and enantio-separated. By using the proposed method, changes in the optical isomer ratio of the hepatic metabolites chlorpheniramine and verapamil caused by differential cytochrome P450 enzyme expression for each isomer, could be successfully traced.

The metallically conductive bis(diimino)nickel framework (NiDI), an emerging class of metal-organic framework (MOF) analogues consisting of two-dimensional (2D) coordination networks, was found to have an energy storage principle that uses both cation and anion insertion. This principle gives high energy led by a multielectron transfer reaction: Its specific capacity is one of the highest among MOF-based cathode materials in rechargeable energy storage devices, with stable cycling performance up to 300 cycles. This mechanism was studied by a wide spectrum of electrochemical techniques combined with density-functional calculations. This work shows that a rationally designed material system of conductive 2D coordination networks can be promising electrode materials for many types of energy devices.

Bis(diimino)nickel (NiDI) nanosheet is prepared by two methods of oxidation-promoted interfacial coordination reactions of nickel(II) ions with hexaaminobenzene. The thickness of the large chemically formed NiDI nanosheet can be controlled from atomic layers to thousands of layers. The morphology of electrochemically formed NiDI-modified electrode achievable within a minute suggests longitudinal growth of nanosheets at the surface. Increasing capacity of the NiDI with its amount indicates NiDI as a promising energy storage material.

A graphdiyne (GDY) analogue that features pyrazine as the aromatic core (PR-GDY) was synthesized under air using a liquid/liquid interfacial synthesis. Optical microscopy, SEM, and AFM revealed the sheet morphology of PR-GDY with a typical thickness of 20 nm in AFM, while TEM disclosed its amorphous nature. It served as a metal-free electrocatalyst for the hydrogen evolution reaction (HER) from water. The presence of the butadiynyl linker and terminal ethynyl group, respectively, was confirmed by Raman spectroscopy. Polymerization to PR-GDY afforded optical bandgap narrowing compared with the corresponding monomer. XPS provided a ratio of 2 : 1 for the sp and sp2 carbons. Moreover, a single Gaussian was fitted with the N 1s peak, ascribable to the pyridinic nitrogen. Such selective doping of heteroatoms is hard to realize in carbon materials. PR-GDY was subjected to TGA, such that its thermal stability up to 300 °C was confirmed. N2 adsorption–desorption isotherms featured a typical type I adsorption behavior with micropores, with a Brunauer–Emmett–Teller surface area and mean pore size of 408 m2 g−1 and 0.8 nm, respectively. A series of electrochemical measurements were conducted to evaluate the HER activity of PR-GDY. The HER performance of GDY was only slightly better than that of glassy carbon, while that of PR-GDY was improved significantly in both acidic and basic aqueous media with an onset potential of −275 mV (vs. the reversible hydrogen electrode, RHE), and −475 mV to achieve a current density of 10 mA cm−2 in 0.5 M H2SO4, and –270 and −710 mV in 0.1 M NaHCO3 + 0.1 M Na2CO3. The present work demonstrates experimentally that PR-GDY serves as a metal-free HER electrocatalyst, and manifests that pyridinic nitrogen enhances the electrocatalytic activity of carbon materials.

Two types of multi-functional emissive bis-o-carborane-substituted 1,4-bis(phenylethynyl)benzene molecules were synthesized, and their optical properties were investigated in detail. The pristine o-carborane-substituted molecule CBH simultaneously exhibited dual emission from the locally excited (LE) and twisted intramolecular charge transfer (TICT) states in solution. Originating from changes in the intensity ratios between both emission bands, clear solvatochromic and thermochromic behaviors were observed. Surprisingly, TICT emission was observed even in the solid state. Aggregation- and crystallization-induced emission enhancement (AIEE and CIEE, respectively) were also presented by CBH. These solid-state emission enhancements could be derived from the suppression of aggregation-caused quenching (ACQ) by the bulky cage structure and the spherical shape of o-carborane. Next, we also synthesized the methyl-substituted derivative (CBMe) and found environment-resistant highly-efficient emission in both the solution and solid states. Finally, CBMe presented mechanochromic luminescence in the solid state. The substituent effects on the optical properties are discussed.