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931.
Inositol 2-dehydrogenase (EC 1.1.1.18) activity appears during growth of Bacillus subtilis (strain 60015) in nutrient sporulation medium. Its synthesis is induced by myo-inositol and repressed by D-glucose. The enzyme has an apparent molecular weight of 155,000 to 160,000 as determined by sucrose density gradient centrifugation, and it is comprised of four subunits, each having a molecular weight of 39,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point of the enzyme is 4.4 as determined by column isoelectric focusing. The enzyme shows the highest Vmax and lowest Km with myo-inositol as substrate but does not react with scyllo-inositol; it also reacts with the alpha anomer (but not the beta anomer) of D-glucose and with D-xylose. Apparently, the enzyme can remove only the single equatorial hydrogen of the cyclitol or pyranose ring. In contrast to the glucose dehydrogenase of spores, which reacts with D-glucose or 2-deoxy-D-glucose and with NAD or NADP, inositol dehydrogenase requires NAD and does not react with 2-deoxy-D-glucose. 相似文献
932.
Ayumu Niida Yoko Kanematsu-Yamaki Tomoko Asakawa Yoshimasa Ishimura Hisashi Fujita Kouta Matsumiya Naoki Nishizawa Yusuke Adachi Taisuke Mochida Kazue Tsuchimori Mariko Yoneyama-Hirozane Junichi Sakamoto Hideki Hirabayashi Hideo Fukui Shiro Takekawa Taiji Asami 《Bioorganic & medicinal chemistry》2018,26(3):566-572
Neuropeptide Y2 receptor (Y2R) agonism is an important anorectic signal and a target of antiobesity drug discovery. Recently, we synthesized a short-length Y2R agonist, PYY-1119 (4-imidazolecarbonyl-[d-Hyp24,Iva25,Pya(4)26,Cha27,36,γMeLeu28,Lys30,Aib31]PYY(23–36), 1) as an antiobesity drug candidate. Compound 1 induced marked body weight loss in diet-induced obese (DIO) mice; however, 1 also induced severe vomiting in dogs at a lower dose than the minimum effective dose administered to DIO mice. The rapid absorption of 1 after subcutaneous administration caused the severe vomiting. Polyethylene glycol (PEG)- and alkyl-modified derivatives of 1 were synthesized to develop Y2R agonists with improved pharmacokinetic profiles, i.e., lower maximum plasma concentration (Cmax) and longer time at maximum concentration (Tmax). Compounds 5 and 10, modified with 20?kDa PEG at the N-terminus and eicosanedioic acid at the Lys30 side chain of 1, respectively, showed high Y2R binding affinity and induced significant body weight reduction upon once-daily administration to DIO mice. Compounds 5 and 10, with their relatively low Cmax and long Tmax, partially attenuated emesis in dogs compared with 1. These results indicate that optimization of pharmacokinetic properties of Y2R agonists is an effective strategy to alleviate emesis induced by Y2R agonism. 相似文献
933.
Dequan Liu Yongliang Yan Yasunari Fujita Donghe Xu 《Molecular breeding : new strategies in plant improvement》2018,38(4):45
Soybean is highly sensitive to photoperiod. To improve the adaptability and productivity of soybean, it is essential to understand the molecular mechanisms regulating flowering time. To identify new flowering time QTLs, we evaluated a BC3F5 population consisting of 120 chromosome segment substitution lines (CSSLs) over 2 years under field conditions. CSSLs were derived from a cross between the cultivated soybean cultivar Jackson and the wild soybean accession JWS156-1, followed by continuous backcrossing using Jackson as the recurrent parent. Four QTLs (qFT07.1, qFT12.1, qFT12.2, and qFT19.1) were detected on three chromosomes. Of these, qFT12.1 showed the highest effect, accounting for 36.37–38.27% of the total phenotypic variation over 2 years. This QTL was further confirmed in the F7 recombinant inbred line population (n?=?94) derived from the same cross (Jackson × JWS156-1). Analysis of the qFT12.1 BC3F5 residual heterozygous line RHL509 validated the allele effect of qFT12.1 and revealed that the recessive allele of qFT12.1 resulted in delayed flowering. Evaluating the qFT12.1 near-isogenic lines (NILs) under different growth conditions showed that NILs with the wild soybean genotype always showed later flowering than those with the cultivated soybean genotype. qFT12.1 was delimited to a 2703-kb interval between the markers BARCSOYSSR_12_0220 and BARCSOYSSR_12_0368 on chromosome 12. qFT12.1 may be a new flowering time gene locus in soybean. 相似文献
934.
Voitto Haukisalmi Sauli Laaksonen Antti Oksanen Kimberlee Beckmen Ali Halajian Tetsuya Yanagida Minoru Nakao 《Parasitology international》2018,67(2):218-224
Phylogenetic relationships of tapeworms of the genus Moniezia Blanchard, 1891 (Cestoda, Anoplocephalidae) parasitizing the Eurasian elk Alces alces, the moose A. americanus and the reindeer/caribou Rangifer tarandus (Cervidae) were studied using DNA sequences of two mitochondrial genes (cox1 and nad1). Several isolates from domestic ruminants, representing Moniezia expansa (Rudolphi, 1810) sensu lato and M. benedeni (Moniez, 1879) sensu lato, and one unidentified isolate from an African antelope, were also included in the analysis.Both genes identified the same six species of Moniezia, but interspecific phylogenetic relationships were better resolved by the nad1 data. The six species of Moniezia comprised two main clades: clade 1 that originates in bovids, with subsequent colonization of northern cervids in Eurasia, and clade 2 that originates in northern cervids, with subsequent specific divergence within these hosts. Clade 2 has a Holarctic distribution.None of the Moniezia specimens in Alces and Rangifer was conspecific with the species in domestic ruminants, suggesting that the custom of identifying Moniezia spp. in northern cervids either as M. expansa or M. benedeni is incorrect. At least two of the species parasitizing Alces and Rangifer have not been previously recognized. These findings challenge the results of all previous studies concerning the diversity and ecology of Moniezia spp. in northern cervids.The traditional classification into three subgenera (Moniezia Blanchard, 1891, Blanchariezia Skrjabin & Schultz, 1937 and Baeriezia Skrjabin & Schultz, 1937), based on the presence and type of interproglottidal glands, conflicts with the currently observed molecular phylogenetic relationships within the genus Moniezia. 相似文献
935.
Miyuki Kusajima Shuhei Shima Moeka Fujita Kiwamu Minamisawa Fang-Sik Che Hiromoto Yamakawa 《Bioscience, biotechnology, and biochemistry》2018,82(9):1522-1526
A bacterial endophyte Azospirillum sp. B510 induces systemic disease resistance in the host without accompanying defense-related gene expression. To elucidate molecular mechanism of this induced systemic resistance (ISR), involvement of ethylene (ET) was examined using OsEIN2-knockdown mutant rice. Rice blast inoculation assay and gene expression analysis indicated that ET signaling is required for endophyte-mediated ISR in rice.
Abbreviations: ACC: 1-aminocyclopropane-1-carboxylic acid; EIN2: ethylene-insensitive protein 2; ET: ethylene; ISR: induced systemic resistance; JA: jasmonic acid; RNAi: RNA interference; SA: salicylic acid; SAR: systemic acquired resistance 相似文献
936.
Miwa Fukuda Tomomi Sasaki Tomoko Hashimoto Hiroyuki Miyachi Minoru Waki Akira Asai Osamu Takikawa Osamu Ohno Kenji Matsuno 《Bioorganic & medicinal chemistry letters》2018,28(17):2846-2849
Kynurenine is biosynthesised from tryptophan catalysed by indoleamine 2,3-dioxygenase (IDO). The abrogation of kynurenine production is considered a promising therapeutic target for immunological cancer treatment. In the course of our IDO inhibitor programme, formal cyclisation of the isothiourea moiety of the IDO inhibitor 1 afforded the 5-Cl-benzimidazole derivative 2b-6, which inhibited both recombinant human IDO (rhIDO) activity and cellular kynurenine production. Further derivatisation of 2b-6 provided the potent inhibitor of cellular kynurenine production 2i (IC50?=?0.34?µM), which unexpectedly exerted little effect on the enzymatic activity of rhIDO. Elucidation of the mechanism of action revealed that compound 2i suppresses IDO expression at the protein level by inhibiting STAT1 expression in IFN-γ-treated A431 cells. The kynurenine-production inhibitor 2i is expected to be a promising starting point for a novel approach to immunological cancer treatment. 相似文献
937.
Nitric oxide-induced salt stress tolerance in plants: ROS metabolism,signaling, and molecular interactions 总被引:2,自引:0,他引:2
Mirza Hasanuzzaman Hirosuke Oku Kamrun Nahar M. H. M. Borhannuddin Bhuyan Jubayer Al Mahmud Frantisek Baluska Masayuki Fujita 《Plant biotechnology reports》2018,12(2):77-92
Nitric oxide (NO), a non-charged, small, gaseous free-radical, is a signaling molecule in all plant cells. Several studies have proposed multifarious physiological roles for NO, from seed germination to plant maturation and senescence. Nitric oxide is thought to act as an antioxidant, quenching ROS during oxidative stress and reducing lipid peroxidation. NO also mediates photosynthesis and stomatal conductance and regulates programmed cell death, thus providing tolerance to abiotic stress. In mitochondria, NO participates in the electron transport pathway. Nitric oxide synthase and nitrate reductase are the key enzymes involved in NO-biosynthesis in aerobic plants, but non-enzymatic pathways have been reported as well. Nitric oxide can interact with a broad range of molecules, leading to the modification of protein activity, GSH biosynthesis, S-nitrosylation, peroxynitrite formation, proline accumulation, etc., to sustain stress tolerance. In addition to these interactions, NO interacts with fatty acids to form nitro-fatty acids as signals for antioxidant defense. Polyamines and NO interact positively to increase polyamine content and activity. A large number of genes are reprogrammed by NO; among these genes, proline metabolism genes are upregulated. Exogenous NO application is also shown to be involved in salinity tolerance and/or resistance via growth promotion, reversing oxidative damage and maintaining ion homeostasis. This review highlights NO-mediated salinity-stress tolerance in plants, including NO biosynthesis, regulation, and signaling. Nitric oxide-mediated ROS metabolism, antioxidant defense, and gene expression and the interactions of NO with other bioactive molecules are also discussed. We conclude the review with a discussion of unsolved issues and suggestions for future research. 相似文献
938.
Takashi Seino Shintaro Kawasaki Mariko Shimokawa Hiroki Tamagawa Kohta Toshimitsu Masayuki Fujii Yuki Ohta Mami Matano Kosaku Nanki Kenta Kawasaki Sirirat Takahashi Shinya Sugimoto Eisuke Iwasaki Junichi Takagi Takao Itoi Minoru Kitago Yuko Kitagawa Takanori Kanai Toshiro Sato 《Cell Stem Cell》2018,22(3):454-467.e6
939.
Evaluation of Francisella tularensis ΔpdpC as a candidate live attenuated vaccine against respiratory challenge by a virulent SCHU P9 strain of Francisella tularensis in a C57BL/6J mouse model
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Deyu Tian Akihiko Uda Eun‐sil Park Akitoyo Hotta Osamu Fujita Akio Yamada Kazuhiro Hirayama Kozue Hotta Yuuki Koyama Mika Azaki Shigeru Morikawa 《Microbiology and immunology》2018,62(1):24-33
Francisella tularensis, which causes tularemia, is an intracellular gram‐negative bacterium. F. tularensis has received significant attention in recent decades because of its history as a biological weapon. Thus, development of novel vaccines against tularemia has been an important goal. The attenuated F. tularensis strain ΔpdpC, in which the pathogenicity determinant protein C gene (pdpC) has been disrupted by TargeTron mutagenesis, was investigated as a potential vaccine candidate for tularemia in the present study. C57BL/6J mice immunized s.c. with 1 × 106 CFUs of ΔpdpC were challenged intranasally with 100× the median lethal dose (LD50) of a virulent SCHU P9 strain 21 days post immunization. Protection against this challenge was achieved in 38% of immunized C57BL/6J mice administered 100 LD50 of this strain. Conversely, all unimmunized mice succumbed to death 6 days post challenge. Survival rates were significantly higher in vaccinated than in unimmunized mice. In addition, ΔpdpC was passaged serially in mice to confirm its stable attenuation. Low bacterial loads persisted in mouse spleens during the first to tenth passages. No statistically significant changes in the number of CFUs were observed during in vivo passage of ΔpdpC. The inserted intron sequences for disrupting pdpC were completely maintained even after the tenth passage in mice. Considering the stable attenuation and intron sequences, it is suggested that ΔpdpC is a promising tularemia vaccine candidate. 相似文献
940.