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991.
992.
993.
Tetsuo Fukuzumi Hiroyasu Takahara Hajime Kaneko Isao Ōnishi 《Bioscience, biotechnology, and biochemistry》2013,77(10):967-969
Some physico-chemical and enzymatic properties of four fractions of glucoamylase, isolated and purified from a culture of Aspergillus oryzae on rice, have been investigated in order to characterize and differentiate the components. Although four fractions were homogeneous in sedimentation analysis, only two fractions were found to be homogeneous in electrophoresis. One of the components had a molecular weight of 69,000 and an isoelectric point of 3.3. Four components resembled one another in their properties, except minute differences in their electrophoretic mobilities, sedimentation coefficients and pH-stabilities. These differences as well as those in the chromatographic behaviors suggest slight differences in the structures of the components. Nevertheless, the properties of these components, except the molecular dimension, were very similar to those of Taka-amylase B, which was isolated from Taka-diastase by Okazaki. 相似文献
994.
Globomycin inhibited the incorporation of [14C]diaminopimeric acid (Dap) into the cold 5% TCA insoluble fraction of Escherichia coli H2143 at higher concentrations than the minimum inhibitory concentration (MIC).One-sixth or -seventh molecules of the lipoprotein were found per one molecule of N-acetyl glucosamine (GlucNAc) or Dap in globomycin-treated cells as compared with one-twelfth or -thirteenth molecules in normal cells. Among globomycin-resistant cells isolated, one-tenth were lipoprotein-less mutants and they showed a slightly swollen form and leaked RNase into the medium. It was interesting that spheroplast formation of the mutants in the presence of the antibiotic was not observed even at a high concentration. 相似文献
995.
Jiro Sawada Hajime Yasui Toshiro Amamoto Masao Yamada Tadayasu Okazaki Ichiro Tanaka 《Bioscience, biotechnology, and biochemistry》2013,77(12):2559-2561
A new nematicidal alkaloid, peniprequinolone (1), together with the known alkaloids penigequinolones A and B (2a, 2b), 3-methoxy-4-hydroxy-4-(4′-methoxyphenyl)quinolinone (3), and 3-methoxy-4,6-dihydroxy-4-(4′-methoxyphenyl)quinolinone (4), were isolated from Penicillium cf. simplicissimum (Oudemans) Thom. Cyclopenin (5) and a compound (6a/6b) structurally related to cyclopenin also were isolated from the fungus, and their structures were established by spectroscopic analysis. The biological activities of 1, 2, 3, 4, and 5 were examined by a bioassay with root-lesion nematodes. 相似文献
996.
Taisaku Tanaka Hajime Sugawara Hiroshi Maruoka Seiichi Imajo Tsuyoshi Muto 《Bioorganic & medicinal chemistry》2013,21(14):4233-4249
A novel series of 6-benzyl substituted 4-aminocarbonyl-1,4-diazepane-2,5-diones were explored as human chymase inhibitors using structure-based drug design according to the X-ray cocrystal structure of chymase and compound 1. The optimization focused on the prime site led to the attainment of compounds that showed potent inhibitory activity, and among them, 18R shows a novel interaction mode. 相似文献
997.
Kitai Y Fukuda H Enomoto T Asakawa Y Suzuki T Inouye S Handa H 《Journal of biotechnology》2011,155(2):251-256
Simian virus 40 (SV40) virus-like particles (VLPs) are efficient nanocarriers for gene delivery. VLPs conjugated to human epidermal growth factor (hEGF) were prepared and the cell selectivity of the VLP was examined using human epithelial carcinoma A431 cells, which overexpress the EGF receptor. The endocytic efficiency was determined by the level of Gaussia luciferase activity from the encapsulated protein in hEGF-conjugated VLPs. EGF receptor-mediated endocytosis of hEGF-conjugated VLPs was significantly increased and was confirmed by fluorescence imaging using mCherry encapsulated in hEGF-conjugated VLPs. These results suggest that VLPs of SV40 conjugated to a specific ligand could be used for cell selective gene delivery. 相似文献
998.
Myint Omar Tsujimoto Hajime Ohnishi Nobuhiro Takeyama Tomohiro Kohda Masanori 《Journal of Ethology》2011,29(1):153-159
Theory predicts that individuals should adopt counterstrategies against intersexual conflict with their mating partners if
the counterstrategies are effective and cost-efficient. In fishes, males with parental care often cannibalize their own offspring,
which reduces the female’s fitness and creates intersexual conflicts. Males of the goby Rhinogobius flumineus cannibalize more eggs in the nest when they have access to additional females prior to spawning. Thus, it is predicted that
females will strategically avoid spawning with males that have high mate availability. In the present study, we experimentally
tested this prediction. When sexual pairs were placed in tanks, most females (control females; 21/22) successfully spawned
inside the nest. In contrast, when a gravid female (stimulus female) that was housed in a small transparent cage was shown
to the experiment pairs prior to spawning, only about half of the females (experiment females; 16/29) spawned inside the nest;
the remaining females released unfertilized eggs outside of the nest. Moreover, experiment females infrequently accepted and
followed males into nests, and delayed spawning more often than control females. R. flumineus females prefer males that court frequently. Indeed, experiment females that infrequently received courtship tended to spawn
outside of the nest. However, infrequent courtship alone could not explain outside-nest spawning, delay in spawning, or the
shorter stay of females in nests. These results imply that the presence of a stimulus female dampens female spawning with
males. We suggest that R. flumineus females may strategically reject or hesitate to spawn with males that have high mate availability, and that this spawning
avoidance may be a counterstrategy against male filial cannibalism. 相似文献
999.
We observed a three-dimensional up-and-down movement of an actin filament sliding on heavy mero-myosin (HMM) molecules in an in vitro motility assay. The up-and-down movement occurred along the direction perpendicular to the planar glass plane on which the filament demonstrated a sliding movement. The height length of the up-and-down movement was measured by monitoring the extent of diminishing fluorescent emission from the marker attached to the filament in the evanescent field of attenuation. The height lengths whose distribution exhibits a local maximum were found around the two values, 150 nm and 90 nm, separately. This undulating three-dimensional movement of an actin filament suggests that the interactions between myosin (HMM) molecules and the actin filament may temporally be modulated during its sliding movement. 相似文献
1000.
Shimazu T Otani H Yoshioka K Fujita M Okazaki T Iwasaka T 《American journal of physiology. Heart and circulatory physiology》2011,301(5):H2061-H2072
Uncoupling of nitric oxide synthase (NOS) has been implicated in left ventricular (LV) remodeling and dysfunction after myocardial infarction (MI). We hypothesized that inducible NOS (iNOS) plays a crucial role in LV remodeling after MI, depending on its coupling status. MI was created in wild-type, iNOS-knockout (iNOS(-/-)), endothelial NOS-knockout (eNOS(-/-)), and neuronal NOS-knockout (nNOS(-/-)) mice. iNOS and nNOS expressions were increased after MI associated with an increase in nitrotyrosine formation. The area of myocardial fibrosis and LV end-diastolic volume and ejection fraction were more deteriorated in eNOS(-/-) mice compared with other genotypes of mice 4 wk after MI. The expression of GTP cyclohydrolase was reduced, and tetrahydrobiopterin (BH(4)) was depleted in the heart after MI. Oral administration of sepiapterin after MI increased dihydrobiopterin (BH(2)), BH(4), and BH(4)-to-BH(2) ratio in the infarcted but not sham-operated heart. The increase in BH(4)-to-BH(2) ratio was associated with inhibition of nitrotyrosine formation and an increase in nitrite plus nitrate. However, this inhibition of NOS uncoupling was blunted in iNOS(-/-) mice. Sepiapterin increased capillary density and prevented LV remodeling and dysfunction after MI in wild-type, eNOS(-/-), and nNOS(-/-) but not iNOS(-/-) mice. N(ω)-nitro-L-arginine methyl ester abrogated sepiapterin-induced increase in nitrite plus nitrate and angiogenesis and blocked the beneficial effects of sepiapterin on LV remodeling and function. These results suggest that sepiapterin enhances angiogenesis and functional recovery after MI by activating the salvage pathway for BH(4) synthesis and increasing bioavailable nitric oxide predominantly derived from iNOS. 相似文献