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91.
J Sivaguru Takehiko Wada Yumi Origane Yoshihisa Inoue V Ramamurthy 《Photochemical & photobiological sciences》2005,4(1):119-127
The photochemistry of optically pure isomers of alpha-methylbenzylamide of trans-2,3-diphenylcyclopropane-1-carboxylic acid has been examined in isotropic solution and within zeolites. The results suggest that these isomerize through cleavage of C2-C3 bond. The direct excitation in solution leads to non-equilibrating 1,3-singlet diradical intermediates whereas triplet sensitization results in equilibrating 1,3-triplet diradical intermediates. The direct excitation within NaY zeolite seems to result in equilibrating zwitterionic intermediates. Studies on the optically pure trans isomers allow one to understand the mechanism of chiral induction during the photoisomerization of mesocis-2,3-diphenylcyclopropane-1-carboxylic acid. The current study has clarified the nature of the excited states involved during the classic (R)-N-acetyl-1-naphthylethylamine sensitized isomerization of 1,2-diphenylcyclopropane. 相似文献
92.
Modulation of Rat Cecal Microbiota by Administration of Raffinose and Encapsulated Bifidobacterium breve 总被引:1,自引:0,他引:1 下载免费PDF全文
Achmad Dinoto Akarat Suksomcheep Satoshi Ishizuka Hanae Kimura Satoshi Hanada Yoichi Kamagata Kozo Asano Fusao Tomita Atsushi Yokota 《Applied microbiology》2006,72(1):784-792
To investigate the effects of administration of raffinose and encapsulated Bifidobacterium breve JCM 1192T cells on the rat cecal microbiota, in a preclinical synbiotic study groups of male WKAH/Hkm Slc rats were fed for 3 weeks with four different test diets: basal diet (group BD), basal diet supplemented with raffinose (group RAF), basal diet supplemented with encapsulated B. breve (group CB), and basal diet supplemented with both raffinose and encapsulated B. breve (group RCB). The bacterial populations in cecal samples were determined by fluorescence in situ hybridization (FISH) and terminal restriction fragment length polymorphism (T-RFLP). B. breve cells were detected only in the RCB group and accounted for about 6.3% of the total cells as determined by FISH analysis. B. breve was also detected only in the RCB group by T-RFLP analysis. This was in contrast to the CB group, in which no B. breve signals were detected by either FISH or T-RFLP. Increases in the sizes of the populations of Bifidobacterium animalis, a Bifidobacterium indigenous to the rat, were observed in the RAF and RCB groups. Principal-component analysis of T-RFLP results revealed significant alterations in the bacterial populations of rats in the RAF and RCB groups; the population in the CB group was similar to that in the control group (group BD). To the best of our knowledge, these results provide the first clear picture of the changes in the rat cecal microbiota in response to synbiotic administration. 相似文献
93.
Microbial Community in Black Rust Exposed to Hot Ridge Flank Crustal Fluids 总被引:1,自引:0,他引:1 下载免费PDF全文
Satoshi Nakagawa Fumio Inagaki Yohey Suzuki Bjrn Olav Steinsbu Mark Alexander Lever Ken Takai Bert Engelen Yoshihiko Sako Charles Geoffrey Wheat Koki Horikoshi Integrated Ocean Drilling Program Expedition Scientists 《Applied microbiology》2006,72(10):6789-6799
During Integrated Ocean Drilling Program Expedition 301, we obtained a sample of black rust from a circulation obviation retrofit kit (CORK) observatory at a borehole on the eastern flank of Juan de Fuca Ridge. Due to overpressure, the CORK had failed to seal the borehole. Hot fluids from oceanic crust had discharged to the overlying bottom seawater and resulted in the formation of black rust analogous to a hydrothermal chimney deposit. Both culture-dependent and culture-independent analyses indicated that the black-rust-associated community differed from communities reported from other microbial habitats, including hydrothermal vents at seafloor spreading centers, while it shared phylotypes with communities previously detected in crustal fluids from the same borehole. The most frequently retrieved sequences of bacterial and archaeal 16S rRNA genes were related to the genera Ammonifex and Methanothermococcus, respectively. Most phylotypes, including phylotypes previously detected in crustal fluids, were isolated in pure culture, and their metabolic traits were determined. Quantification of the dissimilatory sulfite reductase (dsrAB) genes, together with stable sulfur isotopic and electron microscopic analyses, strongly suggested the prevalence of sulfate reduction, potentially by the Ammonifex group of bacteria. Stable carbon isotopic analyses suggested that the bulk of the microbial community was trophically reliant upon photosynthesis-derived organic matter. This report provides important insights into the phylogenetic, physiological, and trophic characteristics of subseafloor microbial ecosystems in warm ridge flank crusts. 相似文献
94.
Yoshihito Kitamura Satoshi Mori Wen Chen Jun Sumaoka Makoto Komiyama 《Journal of biological inorganic chemistry》2006,11(1):13-16
By using the recently developed man-made DNA cutter [a combination of Ce(IV)/EDTA and two DNA additives], green fluorescent
protein (GFP) was converted to closely related blue fluorescent protein (BFP). The phosphodiester linkages at T196-A200 in
the sense strand of GFP were hydrolyzed by the cutter, and the A1-T196 fragment in the product was selectively connected with
the downstream fragment (C197-A720) of BFP by T4 DNA ligase. This recombination changed three codons in the GFP gene (TGC
at 196–198, TAT at 199–201, and ACC at 502–504) to TCT, CAT, and ATC in BFP, and accordingly three amino acids in GFP (Cys65,
Tyr66, and Thr167) were altered to Ser65, His66, and Ile167. The recombinant gene was successfully expressed in Escherichia coli and emitted blue fluorescence, confirming the absence of undesired side reactions (mutation, deletion, insertion, depurination,
etc.) in the DNA manipulation.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
95.
Shigeru Takeshita Maki Moritani Kiyoshi Kunika Hiroshi Inoue Mitsuo Itakura 《Mammalian genome》2006,17(9):927-940
To identify novel genetic modifiers of type 2 diabetes (T2D), we performed quantitative trait loci (QTL) analysis on F2 progeny of hypoinsulinemic diabetic Akita mice, heterozygous for the Ins2 gene Cys96Tyr mutation, and nondiabetic A/J mice. We generated 625 heterozygous (F2-Hetero) and 338 wild-type (F2-Wild) mice with regard to the Ins2 mutation in F2 intercross progeny. We measured quantitative traits, including plasma glucose and insulin concentrations during the intraperitoneal
glucose tolerance test (IPGTT), and body weight (BW). We observed three significant QTLs in hypoinsulinemic hyperglycemic
male F2-Hetero mice, designated Dbm1, Dbm3, and Dbm4 on Chromosomes 6, 14, and 15, respectively. They showed linkage to plasma glucose concentrations, with significant maximum
logarithm of odds (LOD) scores of 4.12, 4.17, and 6.17, respectively, all exceeding threshold values by permutation tests.
In normoinsulinemic normoglycemic male F2-Wild mice, Dbm1 on Chromosome 6 showed linkage to both plasma insulin concentrations and BW, and Dbm2 on Chromosome 11 showed linkage to plasma glucose concentrations only, with LOD scores of 4.52 and 6.32, and 5.78, respectively.
Based on these results, we concluded that Dbm1, Dbm2, Dbm3, and Dbm4 represent four major modifier QTLs specifically affecting T2D-related traits and that these diabetic modifier QTLs are conditional
on the heterozygous Ins2 gene mutation and sex to exert their modifier functions. Identification of the genes responsible for these QTLs would provide
new drug development targets for human T2D.
Electronic Supplementary Material Electronic Supplementary material is available for this article at
and accessible for authorised users. 相似文献
96.
K. Kakimoto H. Inoue N. Hinomoto T. Noda K. Hirano T. Kashio K. Kusigemati S. Okajima 《Biological Control》2006,37(3):314-319
The predation potential of Haplothrips brevitubus (Karny) for thrips was evaluated in the laboratory. When second stage larvae of Pseudodendrothrips mori (Niwa) were presented to an adult H. brevitubus at densities of 10, 20, 30, and 40 larvae per cage at 25 °C over 24 h, the number of larvae consumed per day increased with an increasing density up to 30. Predation of H. brevitubus exhibited the type II functional response. The mean development time of the egg, larva, and pupa of H. brevitubus were 4.5, 9.6, and 4.8 days, respectively, at 25 °C. The survival rate from egg to adult emergence was 94.7%. One H. brevitubus larva consumed 41.6 P. mori larvae on average during the total larval period. Adult longevity was 35.2 days in females and 34.6 days in males. The pre-oviposition period was 2.7 days and the oviposition period was 31.5 days. The lifetime fecundity was 120.1 eggs and the mean daily oviposition rate was 3.6 eggs. Calculated mean generation time (T) was 29.5 days, intrinsic rate of natural increase (rm) was 0.162, and net reproductive rate (R0) was 56.5. The rm value of H. brevitubus was higher than that of Thrips palmi Karny and almost equal to that of Frankliniella occidentalis (Pergande). These results indicate that H. brevitubus has good potential as a predator of P. mori and is likely to be useful for controlling thrips. 相似文献
97.
Takamitsu Utsukihara Satoshi Watanabe Atsushi Tomiyama Wen Chai C. Akira Horiuchi 《Journal of Molecular Catalysis .B, Enzymatic》2006,41(3-4):103-109
Reduction of (+)-and (−)-camphorquinones (1a, 1b) by various vegetables (carrot, potato, sweet potato, apple, Japanese radish, cucumber, burdock and onion) gave -hydroxycamphor selectively. Using burdock, (+)-camphorquinone was reduced to give (−)-3S-exo-hydroxycamphor (4a) as major product in high stereoselectivity with high yield. Moreover, 1,2-cyclohexanedione (1c) and 2-methylcyclohexanone (1d) with various vegetables afford enantiomerically pure trans- and/or cis-alcohol, respectively. Various vegetable reduction gave a new idea of a biotechnological process. 相似文献
98.
99.
Yohsuke Ohba Eriko Kage‐Nakadai Naoko H Tomioka Nozomu Kono Rieko Imae Asuka Inoue Junken Aoki Naotada Ishihara Shohei Mitani Hiroyuki Arai 《The EMBO journal》2013,32(9):1265-1279
Glycerol‐3‐phosphate acyltransferase (GPAT) is involved in the first step in glycerolipid synthesis and is localized in both the endoplasmic reticulum (ER) and mitochondria. To clarify the functional differences between ER‐GPAT and mitochondrial (Mt)‐GPAT, we generated both GPAT mutants in C. elegans and demonstrated that Mt‐GPAT is essential for mitochondrial fusion. Mutation of Mt‐GPAT caused excessive mitochondrial fragmentation. The defect was rescued by injection of lysophosphatidic acid (LPA), a direct product of GPAT, and by inhibition of LPA acyltransferase, both of which lead to accumulation of LPA in the cells. Mitochondrial fragmentation in Mt‐GPAT mutants was also rescued by inhibition of mitochondrial fission protein DRP‐1 and by overexpression of mitochondrial fusion protein FZO‐1/mitofusin, suggesting that the fusion/fission balance is affected by Mt‐GPAT depletion. Mitochondrial fragmentation was also observed in Mt‐GPAT‐depleted HeLa cells. A mitochondrial fusion assay using HeLa cells revealed that Mt‐GPAT depletion impaired mitochondrial fusion process. We postulate from these results that LPA produced by Mt‐GPAT functions not only as a precursor for glycerolipid synthesis but also as an essential factor of mitochondrial fusion. 相似文献
100.
Mao Horio Tamaki Ishima Yuko Fujita Ran Inoue Hisashi Mori Kenji Hashimoto 《Neurochemistry international》2013
d-Serine, an endogenous co-agonist of the N-methyl-d-aspartate (NMDA) receptor is synthesized from l-serine by serine racemase (SRR). A previous study of Srr knockout (Srr-KO) mice showed that levels of d-serine in forebrain regions, such as frontal cortex, hippocampus, and striatum, but not cerebellum, of mutant mice are significantly lower than those of wild-type (WT) mice, suggesting that SRR is responsible for d-serine production in the forebrain. In this study, we attempted to determine whether SRR affects the level of other amino acids in brain tissue. We found that tissue levels of d-aspartic acid in the forebrains (frontal cortex, hippocampus and striatum) of Srr-KO mice were significantly lower than in WT mice, whereas levels of d-aspartic acid in the cerebellum were not altered. Levels of d-alanine, l-alanine, l-aspartic acid, taurine, asparagine, arginine, threonine, γ-amino butyric acid (GABA) and methionine, remained the same in frontal cortex, hippocampus, striatum and cerebellum of WT and mutant mice. Furthermore, no differences in d-aspartate oxidase (DDO) activity were detected in the forebrains of WT and Srr-KO mice. These results suggest that SRR and/or d-serine may be involved in the production of d-aspartic acid in mouse forebrains, although further detailed studies will be necessary to confirm this finding. 相似文献