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A synergetic combination of a chemical redox reaction and a physical capacitor effect in one electrochemical cell is a promising route to realize both high-energy and high-power-density energy storage. In the present work, we studied the electrochemical properties of a nanohybrid system of polyoxometalate (POM) and graphene (RGO), in which individual POM molecules are adsorbed on the RGO surfaces. The molecular cluster battery (MCB) in which the POM/RGO hybrid was adopted as a cathode active material exhibited a higher battery capacity than the POM/SWNT (single-walled carbon nanotube)-MCB and the microcrystal POM-MCB. The observed capacity for the POM/RGO-MCB was found to be much larger than the theoretical one, as calculated from the redox changes in POM, indicating a cooperative enhancement of the capacitor effects of RGO, induced by the POMs on the RGO surfaces.

We performed electrochemical doping of Cl− ions to the x-form single crystals of a neutral π radical LiPc, in which the structure consists of 1D stacking chains of LiPc and nanochannels parallel to them. It was found that the LiPc crystals on the working electrode were electrochemically oxidized in an acetonitrile solution of tetrabutylammonium chloride (TBA·Cl), exhibiting a crystal-to-crystal transformation to LiPc·Clx (0 < x < 0.5), in which the x value was controlled by the electrochemical potential. The crystal structures of the LiPc·Clx series were successfully solved and refined by X-ray single-crystal analysis, and the obtained structures clearly indicated the presence of Cl− ions in the 1D channels and a systematic structural change in the π stacking chain of LiPc. As the value of x increased, the interplanar distance between the neighboring LiPc molecules decreased, which was associated with a significant enhancement of conductivity. These oxidative-doping effects indicate that the structural and electrical properties of the 1D half-filled electron system of LiPc are governed by electron–electron correlations between the unpaired electrons.

In eukaryotes, heat shock protein 90 (Hsp90) is an essential ATP-dependent molecular chaperone that associates with numerous client proteins. HtpG, a prokaryotic homolog of Hsp90, is essential for thermotolerance in cyanobacteria, and in vitro it suppresses the aggregation of denatured proteins efficiently. Understanding how the non-native client proteins bound to HtpG refold is of central importance to comprehend the essential role of HtpG under stress. Here, we demonstrate by yeast two-hybrid method, immunoprecipitation assays, and surface plasmon resonance techniques that HtpG physically interacts with DnaJ2 and DnaK2. DnaJ2, which belongs to the type II J-protein family, bound DnaK2 or HtpG with submicromolar affinity, and HtpG bound DnaK2 with micromolar affinity. Not only DnaJ2 but also HtpG enhanced the ATP hydrolysis by DnaK2. Although assisted by the DnaK2 chaperone system, HtpG enhanced native refolding of urea-denatured lactate dehydrogenase and heat-denatured glucose-6-phosphate dehydrogenase. HtpG did not substitute for DnaJ2 or GrpE in the DnaK2-assisted refolding of the denatured substrates. The heat-denatured malate dehydrogenase that did not refold by the assistance of the DnaK2 chaperone system alone was trapped by HtpG first and then transferred to DnaK2 where it refolded. Dissociation of substrates from HtpG was either ATP-dependent or -independent depending on the substrate, indicating the presence of two mechanisms of cooperative action between the HtpG and the DnaK2 chaperone system.

Summary The mechanism by which the membrane synthetic machinery might be co-organized with the cell-division architecture during the bacterial cell cycle remains to be investigated. We characterized a key enzyme of phospholipid and fatty acid synthesis in Bacillus subtilis, the acyl–acyl carrier protein phosphate acyltransferase (PlsX), and identified it as a component of the cell-division machinery. Comprehensive interaction analysis revealed that PlsX interacts with FtsA, the FtsZ-anchoring protein. PlsX mainly localized at the potential division site independent of FtsA and FtsZ and then colocalized with FtsA. By multidirectional approaches, we revealed that the Z-ring stabilizes the association of PlsX at the septum and pole. The localization of PlsX is also affected by the progression of DNA replication. PlsX is needed for cell division and its inactivation leads to aberrant Z-ring formation. We propose that PlsX localization is prior to Z-ring formation in the hierarchy of septum formation events and that PlsX is important for co-ordinating membrane synthesis with cell division in order to properly complete septum formation.

Aqueous solution was introduced into the self-assembly of water-insoluble (Bu3NH)3[M(CN)8] (M = W, Mo) and Mn(NO3)2·6H2O to afford two, three-dimensional (3D) coordination polymers (CPs), {[μ8-MV(CN)8MnII2(H2O)2(CH3OH)][NO3]}n (M = W 1, Mo 2), while polymer {[μ4-WV(CN)8MnII2(DMF)8](ClO4)}n (DMF = N,N-dimethylformamide) (3) was crystallized from the reaction of (Bu3NH)3[W(CN)8] and Mn(ClO4)2·6H2O in DMF. All three CPs 1, 2, and 3 have been well-characterized by elemental analysis, infrared spectra, single-crystal X-ray diffraction, as well as thermogravimetric analysis. The single-crystal X-ray structural analysis shows that both CPs 1 and 2 crystallize in the monoclinic crystal system with space group of C2/c and possess the infinite 3D framework in an unprecedented afm1 topology geometry, which is an unreported 4-nodal 4,4,8,8-coordinated net with point symbol {411.612.85}{417.610.8}{45.6}4. Polymer 3 crystallizes in the space group of P42/m as a 3D supermolecule structure, which is constructed by one-di...

The strain of Bacillus subtilis 168 used in laboratories in Japan was distributed in the 1990s when the sequencing consortium commenced operations. After 20 years of use of B. subtilis 168 in many laboratories, observations of variations in growth phenotypes have been reported. In this study, to uncover laboratory-specific variations of B. subtilis 168 strains in Japan, we re-sequenced 11 B. subtilis 168 strains from nine laboratories and analyzed how their genomes differed. We found that the 168 strains from different laboratories differed by 1-7 variations. These variations might have been caused by differences in storage conditions in the laboratories or differences among colonies of the original stock. Based on our results, researchers ought to understand the genetic differences among wild-type (parental) strains in different laboratories and the reference strain by re-sequencing analysis, and ought to pay more attention to the management of laboratory strains.

Lactococcus lactis IO-1 (JCM7638) produces L-lactic acid predominantly when grown at high xylose concentrations, and its utilization is highly desired in the green plastics industry. Therefore it is worthwhile studying its genomic traits. In this study, we focused on (i) genes of possible horizontal transfer derivation (prophages, the nisin-sucrose transposon, and several restriction-modification systems), and (ii) genes for the synthetic pathways of amino acids and vitamins in the IO-1 genome. In view of the results of this analysis, we consider their meanings in strain IO-1.

Three types of mitosis, which are open, closed or semi-open mitosis, function in eukaryotic cells, respectively. The open mitosis involves breakage of the nuclear envelope before nuclear division, whereas the closed mitosis proceeds with an intact nuclear envelope. To understand the mechanism and significance of three types of mitotic division in eukaryotes, we investigated the process of semi-open mitosis, in which the nuclear envelope is only partially broken, in the fission yeast Schizosaccharomyces japonicus. In anaphase-promoting complex/cyclosome (APC/C) mutants of Sz. japonicus, the nuclear envelope remained relatively intact during anaphase, resulting in impaired semi-open mitosis. As a suppressor of apc2 mutant, a mutation of Oar2, which was a 3-oxoacyl-[acyl carrier protein] reductase, was obtained. The level of the Oar2, which had two destruction-box motifs recognized by APC/C, was increased in APC/C mutants. Furthermore, the defective semi-open mitosis observed in an apc2 mutant was restored by mutated oar2+. Based on these findings, we propose that APC/C regulates the dynamics of the nuclear envelope through degradation of Oar2 dependent on APC/C during the metaphase-to-anaphase transition of semi-open mitosis in Sz. japonicus.

Ferrochelatase (FECH) is an essential enzyme for the final step of heme biosynthesis. In green plants, its activity has been reported in both plastids and mitochondria. However, the precise subcellular localization of FECH remains uncertain. In this study, we analyzed the localization of FECH in the unicellular red alga, Cyanidioschyzon merolae. Immunoblot and enzyme activity analyses of subcellular fractions localized little FECH in the plastid. In addition, immunofluorescence microscopy identified that both intrinsic and hemagglutinin (HA)-tagged FECH are localized in the mitochondrion. We therefore conclude that FECH is localized in the mitochondrion in C. merolae.

The freshwater cyanobacterium Synechococcus elongatus PCC 7942 exhibits light-dependent growth. Although it has been reported that DNA replication also depends on light irradiation in S. elongatus 7942, the involvement of the light in the regulation of DNA replication remains unclear. To elucidate the regulatory pathway of DNA replication by light, we studied the effect of several inhibitors, including two electron transport inhibitors, 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) and 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB), on DNA replication in S. elongatus 7942. DCMU inhibited only DNA replication initiation, whereas DBMIB blocked both the initiation and progression of DNA replication. These results suggest that DNA replication depends on the photosynthetic electron transport activity and initiation and progression of DNA replication are regulated in different ways.

Four Bacillus subtilis strains were isolated from traditional fermented foods, and the sequences of their extracellular alkaline proteases (AprE) were analyzed and cloned. The recombinant enzymes synthesized by means of Escherichia coli exhibited high proteolytic activity. AprE CN2 showed hydrolytic activity 4-fold higher than that of AprE 168. This activity was also seen in the presence of relatively high NaCl concentrations.

We report here the draft genome sequences of Bradyrhizobium elkanii strains BLY3-8 and BLY6-1, which are incompatible with Rj 3 genotype soybean cultivars. The genome sequences of these strains will be useful to identify a causal gene for this incompatibility.

Decoding of closely related genomes is now revealing the process of population evolution. In bacteria, population divergence appears associated with a unique set of sequence-specific epigenetic DNA methylation systems, often within restriction-modification (RM) systems. They might define a unique gene expression pattern and limit genetic flux between lineages in population divergence. We addressed the contribution of methylation systems to population diversification in panmictic bacterial species, Helicobacter pylori, which shows an interconnected population structure through frequent mutual recombination. We analyzed complete genome sequences of 28 strains collected in Fukui, Japan. Their nucleotide sequences are closely related although fine-scale analyses revealed two subgroups likely reflecting human subpopulations. Their sequences are tightly connected by homologous recombination. Our extensive analysis of RM systems revealed an extreme variability in DNA methyltransferases, especially in their target recognition domains. Their diversity was, however, not immediately related to the genome sequence diversity, except for very closely related strains. An interesting exception is a hybrid strain, which likely has conserved the methylation gene repertoire from one parent but diversified in sequence by massive acquisition of fragmentary DNA sequences from the other parent. Our results demonstrate how a bacterial population can be extremely divergent in epigenetics and yet homogenized in sequence.

Hmo1, a member of HMGB family proteins in Saccharomyces cerevisiae, binds to and regulates the transcription of genes encoding ribosomal RNA and ribosomal proteins. The functional motifs of Hmo1 include two HMG-like motifs, box A and box B, and a C-terminal tail. To elucidate the molecular roles of the HMG-like boxes in DNA binding in vivo, we analyzed the DNA-binding activity of various Hmo1 mutants using ChIP or reporter assays that enabled us to conveniently detect Hmo1 binding to the promoter of RPS5, a major target gene of Hmo1. Our mutational analyses showed that box B is a bona fide DNA-binding motif and that it also plays other important roles in cell growth. However, box A, especially its first α-helix, contributes to DNA binding of Hmo1 by inducing self-assembly of Hmo1. Intriguingly, box A mediated formation of oligomers of more than two proteins on DNA in vivo. Furthermore, duplication of the box B partially alleviates the requirement for box A. These findings suggest that the principal role of box A is to assemble multiple box B in the appropriate orientation, thereby stabilizing the binding of Hmo1 to DNA and nucleating specific chromosomal architecture on its target genes.

Cyanobacteria are photosynthetic microorganisms that serve as experimental model organisms for the study of photosynthesis, environmental stress responses, and the production of biofuels. Genetic tools for bioengineering have been developed as a result of such studies. However, there is still room for improvement for the tight control of experimental protein expression in these microorganisms. Here, we describe an expression system controlled by a theophylline-responsive riboswitch that we have constructed in the cyanobacterium Synechocystis sp. PCC 6803. We demonstrate that, in response to different theophylline concentrations, this riboswitch can tightly control green fluorescence protein expression in Synechocystis. Thus, this system is useful as a tool for genetic engineering and the synthetic biology of cyanobacteria.

A series of V-incorporated e-Keggin polyoxometalate-based open framework materials, (NH4)1.8H10 [Zn3Mo11.9V0.1O40] ·6.5H2O, (NH4)1.8H10 [Zn2.7Mo11.6V0.7O40] ·6.5H2O, (NH4)1.8H7 [Zn2.6Mo11.2V1.2O40] ·6H2O, (NH4)2H14 [Mn2.4Mo12V0.2O40] ·5H2O, (NH4)2.2H12 [Mn2.2Mo11.9V0.7O40] ·5H2O, and (NH4)2.2H9 [Mn2.2Mo11.6V1.0O40] ·5H2O, is hydrothermally synthesized from aqueous mixtures of (NH4)6Mo7O24, NH4VO3, Mo, and ZnCl2 or MnO (autoclave, 448 K, 24 h, 53—71% yield of Zn-containing compounds, 35—43% yield of Mn-containing compounds).

Tropolone, a phytotoxin produced by Burkholderia plantarii , causes rice seedling blight. To identify genes involved in tropolone synthesis, we systematically constructed mutations in the genes encoding 55 histidine kinases and 72 response regulators. From the resulting defective strains, we isolated three mutants, KE1, KE2, and KE3, in which tropolone production was repressed. The deleted genes of these mutants were named troR1 , troK , and troR2 , respectively. The mutant strains did not cause rice seedling blight, and complementation experiments indicated that TroR1, TroK, and TroR2 were involved in the synthesis of tropolone in B. plantarii . However, tropolone synthesis was repressed in the TroR1 D52A, TroK H253A, and TroR2 D46A site-directed mutants. These results suggest that the putative sensor kinase (TroK) and two response regulators (TroR1 and TroR2) control the production of tropolone in B. plantarii . IMPORTANCE A two-component system is normally composed of a sensor histidine kinase (HK) and a cognate response regulator (RR) pair. In this study, HK (TroK) and two RRs (TroR1 and TroR2) were found to be involved in controlling tropolone production in B. plantarii . These three genes may be part of a bacterial signal transduction network. Such networks are thought to exist in other bacteria to regulate phytotoxin production, as well as environmental adaptation and signal transduction.

Eudistomin C (EudiC), a natural product, shows potent antitumor and antiviral activities, but the target molecule and the mechanism of action remain to be revealed. Here, we show that the 40S ribosome is the target in EudiC cytotoxicity. We isolated EudiC-resistant mutants from a multidrug-sensitive yeast strain, and a genetic analysis classified these YER (yeast EudiC resistance) mutants into three complementation groups. A genome-wide study revealed that the YER1-6 mutation is in the uS11 gene (RPS14A). Biotinylated EudiC pulled down Rps14p-containing complexes from 40S and 80S ribosomes, but not from the 60S ribosome. EudiC strongly inhibited translation of the wild-type strain but not of YER1-6 in cells and in vitro. These results indicate that EudiC is a protein synthesis inhibitor targeting the uS11-containing ribosomal subunit, and shows cytotoxicity by inhibiting protein translation.

To understand the induction of the adaptive response under various stress conditions, it is important to determine the partnership between histidine kinase and response regulators in the bacterial two-component system (TCS). The genes encoding TCS partners are usually comprised of an operon in the genome, but many of them are orphans in the cyanobacterial genome. There is little information on their partnerships in Synechococcus elongatus PCC 7942. Our comprehensive analysis of protein-protein interactions among all 37 full-length proteins and the truncated domains of 24 orphans revealed a number of specific interactions. They involved evolutionarily well-conserved orphan proteins among cyanobacterial species such as Synpcc7942_0453/Ycf29, NblS/RpaB, NblS/SrrA, SasA/RpaA, and SasA/Synpcc7942_2466. Our investigation of the transphosphorylation of interaction partners indicates that orphan TCSs comprise a complex signaling network.

We carried out in operando Mo K-edge X-ray absorption fine structure measurements on the rechargeable molecular cluster batteries (MCBs) of polyoxometalates (POMs), in which a Keggin-type POM, [PMo(12)O(40)](3-), is utilized as a cathode active material with a lithium metal anode. The POM-MCBs exhibit a large capacity of ca. 270 (A h)/kg in a voltage range between V = 4.0 V and V = 1.5 V. X-ray absorption near-edge structure analyses demonstrate that all 12 Mo(6+) ions in [PMo(12)O(40)](3-) are reduced to Mo(4+) in the discharging process. This means the formation of a super-reduced state of the POM, namely, [PMo(12)O(40)](27-), which stores 24 electrons, and this electron number can explain the large capacity of the POM-MCBs. Furthermore, extended X-ray absorption fine structure analyses reveal the molecular structure of [PMo(12)O(40)](27-), which is slightly reduced in size compared to the original [PMo(12)O(40)](3-) and involves Mo(4+) metal-metal-bonded triangles. Density functional theory calculations suggest that these triangles are formed because of the large number of additional electrons in the super-reduced state.

The carbazole-degradative plasmid pCAR1 carries the class II transposon Tn4676, which contains the car and ant genes, essential for conversion of carbazole into anthranilate, and anthranilate into catechol, respectively. In our previous study, DNA rearrangements in pCAR1 were frequently detected in the host Pseudomonas fluorescens Pf0-1 in the presence of carbazole, resulting in the improvement of host survivability. Several Pf0-1 mutants harbouring pCAR1 were isolated, and deletion of DNA in the plasmid ant gene was found. Here, we compared genome sequences of the parent strain Pf0-1L(pCAR1 : : rfp) and one of its mutants, 5EP83, to assess whether other DNA rearrangements occurred in either the plasmid or the host chromosome. We found transposition of Tn4676 into the 5EP83 chromosome. In addition, ISPre1 had transposed into the car gene intergenic region on the pCAR1-derivative plasmid of 5EP83, which inhibited car transcription. As a result of these transpositions, 5EP83 was able to metabolize carbazole due to the Tn4676 on its chromosome, although the car genes on its plasmid were non-functional. We also found that one copy of duplicate carAa genes had been deleted, and that ISPre4 had transposed into both the host chromosome and the plasmid. Our findings suggest that Pf0-1 harbouring pCAR1 is subjected to DNA rearrangements not only on the plasmid but also on its chromosome in the presence of carbazole.

Single-wall carbon nanotubes (SWCNTs) have been synthesized by supported-catalyst chemical vapor deposition (CCVD) using one-dimensional (1D) channels of mesoporous silica (SBA-15; mean channel diameter, 6.0 nm) functionalized with carboxyl groups where Co and Fe complexes are encapsulated. The synthesized SWCNTs have much larger diameters than the SWCNTs synthesized by conventional CCVD. Transmission electron microscope observations reveal that large-diameter SWCNTs (

The cyanobacterium, Synechocystis sp. PCC 6803, was the first photosynthetic organism whose genome sequence was determined in 1996 (Kazusa strain). It thus plays an important role in basic research on the mechanism, evolution, and molecular genetics of the photosynthetic machinery. There are many substrains or laboratory strains derived from the original Berkeley strain including glucose-tolerant (GT) strains. To establish reliable genomic sequence data of this cyanobacterium, we performed resequencing of the genomes of three substrains (GT-I, PCC-P, and PCC-N) and compared the data obtained with those of the original Kazusa strain stored in the public database. We found that each substrain has sequence differences some of which are likely to reflect specific mutations that may contribute to its altered phenotype. Our resequence data of the PCC substrains along with the proposed corrections/refinements of the sequence data for the Kazusa strain and its derivatives are expected to contribute to investigations of the evolutionary events in the photosynthetic and related systems that have occurred in Synechocystis as well as in other cyanobacteria.

Synechocystis sp. PCC 6803 is the most popular cyanobacterial strain, serving as a standard in the research fields of photosynthesis, stress response, metabolism and so on. A glucose-tolerant (GT) derivative of this strain was used for genome sequencing at Kazusa DNA Research Institute in 1996, which established a hallmark in the study of cyanobacteria. However, apparent differences in sequences deviating from the database have been noticed among different strain stocks. For this reason, we analysed the genomic sequence of another GT strain (GT-S) by 454 and partial Sanger sequencing. We found 22 putative single nucleotide polymorphisms (SNPs) in comparison to the published sequence of the Kazusa strain. However, Sanger sequencing of 36 direct PCR products of the Kazusa strains stored in small aliquots resulted in their identity with the GT-S sequence at 21 of the 22 sites, excluding the possibility of their being SNPs. In addition, we were able to combine five split open reading frames present in the database sequence, and to remove the C-terminus of an ORF. Aside from these, two of the Insertion Sequence elements were not present in the GT-S strain. We have thus become able to provide an accurate genomic sequence of Synechocystis sp. PCC 6803 for future studies on this important cyanobacterial strain.

(NBu4)3[PMo12O40] molecules are grafted onto the surface of single-wall carbon nanotubes by addition of a MeCN solution of the polyoxometalate to a toluene suspension of the nanotubes under vigorous stirring at room temperature.

In situ X-ray absorption fine structure (XAFS) analyses were performed on rechargeable molecular cluster batteries (MCBs), which were formed by a lithium anode and cathode-active material, [Mn(12)O(12)(CH(3)CH(2)C(CH(3))(2)COO)(16)(H(2)O)(4)] with tert-pentyl carboxylate ligand (abbreviated as Mn12tPe), and with eight Mn(3+) and four Mn(4+) centers. This mixed valence cluster compound is used in an effort to develop a reusable in situ battery cell that is suitable for such long-term performance tests. The Mn12tPe MCBs exhibit a large capacity of approximately 210 Ah kg(-1) in the voltage range V=4.0-2.0 V. The X-ray absorption near-edge structure (XANES) spectra exhibit a systematic change during the charging/discharging with an isosbestic point at 6555 eV, which strongly suggests that only either the Mn(3+) or Mn(4+) ions in the Mn12 skeleton are involved in this battery reaction. The averaged manganese valence, determined from the absorption-edge energy, decreased monotonically from 3.3 to 2.5 in the first half of the discharging (4.0>V>2.8 V), but changed little in the second half (2.8>V>2.0 V). The former valence change indicates a reduction of the initial [Mn12](0) state by approximately ten electrons, which corresponds well with the half value of the observed capacity. Therefore, the large capacity of the Mn12 MCBs can be understood as being due to a combination of the redox change of the manganese ions and presumably a capacitance effect. The extended X-ray absorption fine structure (EXAFS) indicates a gradual increase of the Mn(2+) sites in the first half of the discharging, which is consistent with the XANES spectra. It can be concluded that the Mn12tPe MCBs would include a solid-state electrochemical reaction, mainly between the neutral state [Mn12](0) and the super-reduced state [Mn12](8-) that is obtained by a local reduction of the eight Mn(3+) ions in Mn12 toward Mn(2+) ions.

Molecular breeding approaches are of growing importance to crop improvement. However, closely related cultivars generally used for crossing material lack sufficient known DNA polymorphisms due to their genetic relatedness. Next-generation sequencing allows the identification of a massive number of DNA polymorphisms such as single nucleotide polymorphisms (SNPs) and insertions-deletions (InDels) between highly homologous genomes. Using this technology, we performed whole-genome sequencing of a landrace of japonica rice, Omachi, which is used for sake brewing and is an important source for modern cultivars. A total of 229 million reads, each comprising 75 nucleotides of the Omachi genome, was generated with 45-fold coverage and uniquely mapped to 89.7% of the Nipponbare genome, a closely related cultivar. We identified 132,462 SNPs, 16,448 insertions and 19,318 deletions between the Omachi and Nipponbare genomes. An SNP array was designed to validate 731 selected SNPs, resulting in validation rates of 95 and 88% for the Omachi and Nipponbare genomes, respectively. Among the 577 SNPs validated in both genomes, 532 are entirely new SNP markers not previously reported between related rice cultivars. We also validated InDels on a part of chromosome 2 as DNA markers and successfully genotyped five japonica rice cultivars. Our results present the methodology and extensive data on SNPs and InDels available for whole-genome genotyping and marker-assisted breeding. The polymorphism information between Omachi and Nipponbare is available at NGRC_Rice_Omachi (http://www.nodai-genome.org/oryza_sativa_en.html).

Treatment of molecular building block [W(CN)8]3− with Co(NO3)2·6H2O or Cu(ClO4)2·6H2O in different reaction conditions affords two 3D (three-dimensional) metalloligand-bridged coordination polymers {[WV(CN)8Co2(DMF)8][NO3]}n1 and {WIV(CN)8Cu2(py)8}n2, respectively. The single-crystal X-ray structural analysis shows that both polymers 1 and 2 crystallize in the tetragonal crystal system with space group of I41/a and possess the similar 3D framework in a diamondoid topology geometry, although [W(CN)8]3− ion was reduced into [W(CN)8]4− in polymer 2 during the reaction process. The magnetic studies on coordination polymers 1 and 2 indicate that polymer 1 shows the typical ferromagnetic property with an ordering temperature of about 5 K but polymer 2 exhibits paramagnetic behavior due to the diamagnetic octacyanometalate bridge –NC–WIV(S = 0)–CN–.

We demonstrated that the performance of the polyoxometalate molecular cluster battery (POM-MCB) is significantly dependent on the weight ratio of POM in the cathodes; the discharge capacities per u...

A novel iridium complex with an iminonitroxide bipyridine ligand, [Ir(ppy) 2 (MebpyIN)]Cl (ppy = 2-phenylpyridine and MebpyIN = 4-methyl-4'-(1-oxyl-4,4,5,5-tetramethylimidazolin-2-yl)-2,2'-bypyridine), was prepared as a preluminescent probe to detect free radicals. Although a related material, [Ir(ppy) 2 (bpy)]Cl, exhibits strong red luminescence, the emission of [Ir(ppy) 2 (MebpyIN)]Cl was quenched nearly completely by the nitronyl radical moiety in the ligand. However, the carbon-centered free radicals, generated from azobisbutyronitrile by UV irradiation, brought about a dramatic recovery of the luminescence of [Ir(ppy) 2 (MebpyIN)]Cl, with a linear relation between the luminescence intensity, and the free radical concentrations up to 120 mM. EPR measurements indicated that the luminescence recovery was caused by the free radical trapping at the nitronyl-radical moiety.

In accordance with the detailed balance limit model of single-intermediate-band solar cells (IBSCs), the optimum matrix bandgap and IB–conduction band (CB) energy gap are ~1.9 and 0.7 eV, respectively. We present the room-temperature polarized infrared absorption of 20 stacked InAs quantum dot (QD) structures in the Al0.32Ga0.68As matrix with a bandgap of ~1.9 eV for the design of high-efficiency IBSCs by using a multipass waveguide geometry. We find that the IB–CB absorption is almost independent of the light polarization, and estimate the magnitude of the absorption per QD layer to be ~0.01%. We also find that the IB–CB absorption edge of QD structures with a wide-gap matrix is ~0.41 eV. These results indicate that both the significant increase in the magnitude of IB–CB absorption and the lower energy of the IB state for the higher IB–CB energy gap are necessary toward the realization of high-efficiency IBSCs.

Magnetic hollow spheres with a controlled diameter and shell thickness have emerged as an important class of magnetic nanomaterials. The confined hollow geometry and pronouncedly curved surfaces induce unique physical properties different from those of flat thin films and solid counterparts. In this paper, we focus on recent progress on submicron-size spherical hollow magnets (e.g., cobalt- and iron-based materials), and discuss the effects of the hollow shape and the submicron size on magnetic and optical properties.

Thin films of interacting dimers of 4,4′-bis(1,2,3,5-dithiadiazolyl), sandwiched by ITO and Al, exhibit an anomalous transient current, due to a significant imbalance between the hole and electron mobilities and bulk polarization. We propose a new operational principle for organic optoelectronic conversion systems, which efficiently generates alternating photocurrent without being affected by the disadvantages of organic materials, such as poor mobility.

Transposons play a significant role in the evolution of bacterial genomes. Quantifying frequency of transpositional events caused by a transposon will facilitate understanding its role. Here, we report successful measurement of the frequency of IS1 transposition using "GFP hop-on assay" in which transposition-dependent GFP expression is monitored by FACS. This assay allows easy assessment of IS transposition into the chromosomal DNA on a single-cell scale; this is an advantage over other conventional methods to measure transposition frequency.

The present study describes the designed synthesis, X-ray structures, and magnetic properties of two 3D cyano-bridged heterobimetallic tungsten/molybdenum(IV)−copper(II) MOFs, {[μ4-M(CN)8]Cu2(DPP)4}n (M = W 1, Mo 2; DPP = 1,3-Di(4-pyridyl)propane). Both MOFs 1 and 2 were constructed by interdiffusion approach in two steps: the first reaction of CuSCN and NH4SCN with the flexible bridging ligand DPP in polar solvent for building a 2D homometallic Cu polymer, and the thereafter conformation of 3D heterobimetallic MOF architectures with [M(CN)8]3− and 2D coordination networks. MOFs 1 and 2 are isomorphous and both crystallize in the tetragonal system and have space group I41/a, with unit cell constants a = 19.734(3) A, b = 19.734(3) A, c = 13.989(2) A for 1, and a = 19.7429(19) A, b = 19.7429(19) A, c = 13.9883(15) A for 2. Our study demonstrates that such heterobimetallic MOFs possess a unique 2D → 3D architecture and exhibit a new 2-nodal topological structure. The magnetic measurement of MOFs shows typica...

We have examined the crystal structures and the electrical and magnetic properties of the molecular compounds of a thiazyl radical, 1,3,2-benzodithiazolyl (abbreviated as BDTA). BDTA was found to be a useful building block for molecular conductors and magnets because it can operate as a counter cation, a donor or a ligand, depending on its charge. (i) A charge-transfer complex, [BDTA][TCNQ], crystallizes into a uniform segregated stacking structure with a short contact between the donor and acceptor columns. In spite of the partial charge transfer between the two components, this complex exhibits semiconductive behaviour, probably due to a large electron correlation on BDTA. (ii) The crystal structure of [BDTA][Ni(mnt)2] (mnt = maleonitriledithiolate) consists of alternating stacking columns of S = 0 [BDTA]+ and S = 1/2 [Ni(mnt)2]−, in which a ferromagnetic coupling operates between the [Ni(mnt)2]− anions through the [BDTA] + cation. (iii) [BDTA]2[Cu(mnt)2] consists of an alternating stack of a head-to-head [BDTA]+ dimer and a planar [Cu(mnt)2]2− dianion. Short intermolecular S⋯S contacts between the stacks give rise to an ideal 1D Heisenberg antiferromagnetic chain of [Cu(mnt)2]2− with a coupling constant of J/kB = 16–17 K. (iv) The crystal structure of [BDTA]2[Co(mnt)2] is similar to that of [BDTA]2[Cu(mnt)2] at 253 K, but this salt undergoes a phase transition at 190 K, below which a partial electron transfer occurs from [Co(mnt)2]2− to one of the [BDTA]+ cations along with formation of a coordination bond. (v) [BDTA][Ni(dmit)2]2 (dmit = 1,3-dithiol-2-thione-4,5-dithiolate) exhibits room-temperature conductivity of 0.1 S cm−1 and semiconductive behaviour over the range 80–200 K, which can be interpreted in terms of multi-conducting bands.

Crystalline ErCl3 nanowires have been fabricated in single-walled carbon nanotubes (SWCNTs) with high yield (∼90%), and the structural and magnetic properties of the resulting ErCl3 nanowires encapsulated in SWCNTs (ErCl3@SWCNTs) characterized. Encapsulation under high temperature and vacuum using high quality SWCNTs results in a high filling-ratio of ErCl3 nanowires in the SWCNTs. The high filling-ratio of ErCl3 nanowires and the use of highly pure SWCNTs with only a small amount of residual Fe catalyst nanoparticles enabled us to observe the magnetic properties of ErCl3@SWCNTs. Structure determination based on simulated annealing calculations and high-resolution transmission electron microscope (HRTEM) image simulations revealed that the structure of the ErCl3 nanowires is unusual with respect to the coordination environment of the Eu3+ ions. This work opens up new possibilities to fabricate various metal complex nanowires with high yield and may also be of more general importance in understanding and exploring magnetic properties in low-dimensional magnetic systems.

Uroporphyrinogen decarboxylase (HemE) is important due to its location at the first branch-point in tetrapyrrole biosynthesis. We detected a complex formation between full-length polypeptides of HtpG and HemE by biochemical studies in vivo and in vitro. The interaction suppressed the enzyme activity, suggesting a regulatory role of HtpG in tetrapyrrole biosynthesis.

A response regulator, NblR, of the cyanobacterium Synechococcus elongatus PCC 7942 is known to induce expression of the nblA gene, a key factor in phycobilisome degradation (bleaching) under nutrient-deprivation conditions. In this study, we observed phosphorylation-independent regulation of NblR activity. We constructed a mutant strain expressing NblR (D57A), in which a putative phospho-accepting Asp-57 was replaced with Ala residue. Under nitrogen deprivation, this strain exhibited the typical bleaching phenotype observed in wild-type cells. Moreover, in the mutant, the nblA transcript accumulated at a level similar to that of the wild type. Our results indicate that activation of NblR is independent of phosphorylation, if any, by a cognate histidine kinase. Screening of proteins interacting with NblR by yeast two-hybrid analysis revealed two candidates, MreC and NarB, suggesting a novel mechanism that activates NblR, or other functions of the response regulator.

We studied the effect of changing temperature on the mechanical properties of nanosized poly(methyl methacrylate) wires fabricated by two-photon fabrication. At around room temperature, the nanowires showed a transition temperature where the shear modulus suddenly changed. This transition temperature was observed to decrease more than 40 K by decreasing the radius of the nanowires from 450 to 150 nm. This size is several times larger in nanowires than reported values of polymer thin film thickness showing a depression of the glass transition temperature.