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31.
32.
Koyama M Katayama S Kaji M Taniguchi Y Matsushita O Minami J Morita S Okabe A 《Microbiology and immunology》1999,43(10):947-957
The hem gene cluster, which consists of hemA, cysG(B), hemC, hemD, hemB, and hemL genes, and encodes enzymes involved in the biosynthetic pathway from glutamyl-tRNA to uroporphyrinogen III, has been identified by the cloning and sequencing of two overlapping DNA fragments from Clostridium perfringens NCTC8237. The deduced amino acid sequence of the N-terminal region of C. perfringens HemD is homologous to those reported for the C-terminal region of Salmonella typhimurium CysG and Clostridium josui HemD. C. perfringens CysG(B) is a predicted 220-residue protein which shows homology to the N-terminal region of S. typhimurium CysG. Disruption of the cysG(B) gene in C. perfringens strain 13 by homologous recombination reduced cobalamin (vitamin B12) levels by a factor of 200. When grown in vitamin B12-deficient medium, the mutant strain showed a four-fold increase in its doubling time compared with that of the wild-type strain, and this effect was counteracted by supplementing the medium with vitamin B12. These results suggest that C. perfringens CysG(B) is involved in the chelation of cobalt to precorrin II as suggested for the CysG(B) domain of S. typhimurium CysG, enabling the synthesis of cobalamin. 相似文献
33.
Hiroshi Morita Yuichiro Tomizawa Jun Deguchi Tokio Ishikawa Hiroko Arai Kazumasa Zaima Takahiro Hosoya Yusuke Hirasawa Takayuki Matsumoto Katsuo Kamata Wiwied Ekasari Aty Widyawaruyanti Tutik Sri Wahyuni Noor Cholies Zaini Toshio Honda 《Bioorganic & medicinal chemistry》2009,17(24):8234-8240
Cassiarin A 1, a tricyclic alkaloid, isolated from the leaves of Cassia siamea (Leguminosae), shows powerful antimalarial activity against Plasmodium falciparum in vitro as well as P. berghei in vivo, which may be valuable leads for novel antimalarials. Interactions of parasitized red blood cells (pRBCs) with endothelium in aorta are especially important in the processes contribute to the pathogenesis of severe malaria. Nitric oxide (NO) reduces endothelial expression of receptors/adhesion molecules used by pRBC to adhere to vascular endothelium, and reduces cytoadherence of pRBC to vascular endothelium. Cassiarin A 1 showed vasorelaxation activity against rat aortic ring, which may be related with NO production. A series of a hydroxyl and a nitrogen-substituted derivatives and a dehydroxy derivative of 1 have been synthesized as having potent antimalarials against P. falciparum with vasodilator activity, which may reduce cytoadherence of pRBC to vascular endothelium. Cassiarin A 1 exhibited a potent antimalarial activity and a high selectivity index in vitro, suggesting that the presence of a hydroxyl and a nitrogen atom without any substituents may be important to show antimalarial activity. Relative to cassiarin A, a methoxy derivative showed more potent vasorelaxant activity, although it did not show improvement for inhibition of P. falciparum in vitro. These cassiarin derivatives may be promising candidates as antimalarials with different mode of actions. 相似文献
34.
Health resort programs have a long tradition, mainly in European countries and Japan. They rely on local resources and the
physical environment, physical medicine interventions and traditional medicine to optimise functioning and health. Arguably
because of the long tradition, there is only a limited number of high-quality studies that examine the effectiveness of health
resort programs. Specific challenges to the evaluation of health resort programs are to randomise the holistic approach with
a varying number of specific interventions but also the reliance on the effect of the physical environment. Reference standards
for the planning and reporting of health resort studies would be highly beneficial. With the International Classification
of Functioning Disability and Health (ICF), we now have such a standard that allows us to describe body functions and structures,
activities and participation and interaction with environmental factors. A major challenge when applying the ICF in practice
is its length. Therefore, the objective of this project was to identify the ICF categories most relevant for health resort
programs. We conducted a consensus-building, three-round, e-mail survey using the Delphi technique. Based on the consensus
of the experts, it was possible to come up with an ICF Core Set that can serve as reference standards for the indication,
intervention planning and evaluation of health resort programs. This preliminary ICF Core Set should be tested in different
regions and in subsets of health resort visitors with varying conditions. 相似文献
35.
Shigeo Aibara Takahiro Inakuma Yuhei Morita 《Bioscience, biotechnology, and biochemistry》2013,77(11):3051-3052
Penicillium strains (n=394) preserved at NBRC (the NITE Biological Resource Center) were compared as to groupings (11 species-clusters) based on phylogeny and the production of bioactive compounds. The strains in two clusters, of which P. chrysogenum and P. citrinum are representative, showed higher rates of positive strains with multi-biological activities. 相似文献
36.
Morita T Kumakura N Morishima K Mitsuboshi T Ishida M Hara T Kudo S Miwa M Ihara S Higuchi K Takeuchi Y Yoshizaki G 《Biology of reproduction》2012,86(6):176
Although the yellowtail (Seriola quinqueradiata) is the fish most commonly farmed in Japan, breeding of this species has not yet started. This is primarily due to the lack of sufficiently sophisticated methods for manipulating gametogenesis, which makes it difficult to collect gametes from specific dams and sires. If it were possible to produce large numbers of surrogate fish by transplanting germ cells isolated from donor individuals harboring desirable genetic traits, then the probability of acquiring gametes carrying the donor-derived haplotype would increase, and breeding programs involving this species might increase as a result. As a first step, we established a method for the allogeneic transplantation of yellowtail spermatogonia and the production of donor-derived offspring. Donor cells were collected from immature (10-month-old) yellowtail males with testes containing abundant type A spermatogonia, labeled with PKH26 fluorescent dye, and transferred into the peritoneal cavities of 8-day-old larvae. Fluorescence observation at 28 days post-transplantation revealed that PKH26-labeled cells were incorporated into recipients' gonads. To assess whether donor-derived spermatogonia could differentiate into functional gametes in the allogeneic recipient gonads, gametes collected from nine male and four female adult recipients were fertilized with wild-type eggs and milt. Analysis of microsatellite DNA markers confirmed that some of the first filial (F(1)) offspring were derived from donor fish, with the average contribution of donor-derived F(1) offspring being 66% and the maximum reaching 99%. These findings confirmed that our method was effective for transplanting yellowtail spermatogonia into allogeneic larvae to produce donor-derived offspring. 相似文献
37.
Jun Yoshikawa Tomotake Morita Tokuma Fukuoka Masaaki Konishi Tomohiro Imura Koji Kakugawa Dai Kitamoto 《Applied microbiology and biotechnology》2014,98(2):823-830
Mannosylerythritol (ME) is the hydrophilic backbone of mannosylerythritol lipids as the most promising biosurfactants produced by different Pseudozyma yeasts, and has been receiving attention as a new sugar alcohol. Different Pseudozyma yeasts were examined for the sugar alcohol production using glucose as the sole carbon source. P. hubeiensis KM-59 highly produced a conventional type of ME, i.e., 4-O-β-d-mannopyranosyl-d-erythritol (4-ME). Interestingly, P. tsukubaensis KM-160 produced a diastereomer of 4-ME, i.e., 1-O-β-d-mannopyranosyl-d-erythritol (1-ME). In shake flask culture with 200 g/l of glucose, strain KM-59 produced 4-ME at a yield of 33.2 g/l (2.2 g/l/day of the productivity), while strain KM-160 produced 1-ME at 30.0 g/l (2.0 g/l/day). Moreover, the two strains were found to produce ME from glycerol; the maximum yields of 4-ME and 1-ME from 200 g/l of glycerol were 16.1 g/l (1.1 g/l/day) and 15.8 g/l (1.1 g/l/day), respectively. The production of 1-ME as the new diastereomer was further investigated in fed batch culture using a 5-l jar-fermenter. Compared to the flask culture, strain KM-160 gave three times higher productivity of 1-ME at 38.0 g/l (6.3 g/l/day) from glucose and at 31.1 g/l (3.5 g/l/day) from glycerol, respectively. This is the first report on the selective production of two diastereomers of ME, and should thus facilitate the functional development and application of the disaccharide sugar alcohol in the food and relative industries. 相似文献
38.
Morita H Matsunaga M Mizuno K Fujio Y 《The Journal of General and Applied Microbiology》1998,44(3):211-216
Maximum growth for Rhizopus sp. A-11 was obtained at a zinc ion concentration of 0.7 ppm in a liquid medium. Glucoamylase (GA, EC 3.2.1.3) production in Rhizopus sp. A-11 was maximized at 710 U/ml, at the presence of 75 ppm for calcium and 0.7 ppm of zinc ions in liquid medium. Zinc ion is known as an essential biometal for Rhizopus growth; however, growth was inhibited by the zinc ion concentration, not maximized. Although calcium ion was not necessary to Rhizopus growth, GA production using Rhizopus sp. A-11 was markedly stimulated by calcium ion concentration over 75 ppm in the liquid medium. The GA productivity of the present liquid culture was about 4.4 times higher than that of the solid state culture, based on the unit starch amount in the liquid and solid media carbon source. The characteristics of the GA produced by the Rhizopus sp. A-11 liquid culture were interesting; that is, almost all the GA produced was classified as raw starch-digesting GA (GA-I). Secreted protein in the culture liquid after 30 h was nearly GA, and had a limited amount of impure protein. As a result, it was found that using a Rhizopus culture in a specified metal-ion regulated medium was an effective method for producing GA. Thus the present culture method was renamed the "metal-ion-regulated liquid culture method". 相似文献
39.
Yasuto Watanabe Tatsuhiko Ohe Makoto Morita 《Bioscience, biotechnology, and biochemistry》2013,77(12):2735-2741
The effect of glucose on the formation of uricase by a strain of Streptomyces sp. incubated under conditions of nitrogen limitation was investigated. Glucose stimulated uricase formation in the presence of potassium ion and inhibited it in the absence of the ion. Glucose metabolism by the organism was altered in the absence of the ion, and this appeared to cause the inhibition of the enzyme formation. The stimulatory effect of glucose in the presence of potassium ion was to shorten the lag period. Comparisons of the enzyme formation with and without urate in the presence and absence of glucose revealed that glucose promoted the utilization of exogenous urate as the inducer. The effect of glucose appeared to require protein synthesis, since it was prevented by chloramphenicol. Cyclic adenosine 3′,5′-mono-phosphate showed apparently no effect on uricase formation of this organism. 相似文献
40.
A petal‐specific InMYB1 promoter from Japanese morning glory: a useful tool for molecular breeding of floricultural crops 下载免费PDF全文
Mana Hirose Yasumasa Morita Atsushi Hoshino Shigeru Iida Yoshimi Oshima Nobutaka Mitsuda Masaru Ohme‐Takagi Katsuhiro Shiratake 《Plant biotechnology journal》2016,14(1):354-363
Production of novel transgenic floricultural crops with altered petal properties requires transgenes that confer a useful trait and petal‐specific promoters. Several promoters have been shown to control transgenes in petals. However, all suffer from inherent drawbacks such as low petal specificity and restricted activity during the flowering stage. In addition, the promoters were not examined for their ability to confer petal‐specific expression in a wide range of plant species. Here, we report the promoter of InMYB1 from Japanese morning glory as a novel petal‐specific promoter for molecular breeding of floricultural crops. First, we produced stable InMYB1_1kb::GUS transgenic Arabidopsis and Eustoma plants and characterized spatial and temporal expression patterns under the control of the InMYB1 promoter by histochemical β‐glucuronidase (GUS) staining. GUS staining patterns were observed only in petals. This result showed that the InMYB1 promoter functions as a petal‐specific promoter. Second, we transiently introduced the InMYB1_1 kb::GUS construct into Eustoma, chrysanthemum, carnation, Japanese gentian, stock, rose, dendrobium and lily petals by particle bombardment. GUS staining spots were observed in Eustoma, chrysanthemum, carnation, Japanese gentian and stock. These results showed that the InMYB1 promoter functions in most dicots. Third, to show the InMYB1 promoter utility in molecular breeding, a MIXTA‐like gene function was suppressed or enhanced under the control of InMYB1 promoter in Arabidopsis. The transgenic plant showed a conspicuous morphological change only in the form of wrinkled petals. Based on these results, the InMYB1 promoter can be used as a petal‐specific promoter in molecular breeding of floricultural crops. 相似文献