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71.
Yasuo Nakabayashi Hiroyuki Inada Yuki Minoura Nobuaki Iwamoto Osamu Yamauchi 《Inorganica chimica acta》2009,362(3):869-4841
For reactions of [{RuCl(bpy)2}2(μ-BL)]2+ (bpy = 2,2′-bipyridine, BL = H2N(CH2)nNH2 (n = 4-8, 12), [Ru2-BL]2+) with mononucleotides, the MLCT absorption bands of [Ru2-BL]2+ blue-shifted with hyperchromism for GMP and hypochromism for TMP with time. Reactions of [Ru2-BL]2+ with GMP or TMP proceed via initial Cl− ions replacement by coordination to N7 of GMP and N3 of TMP, respectively. In competition binding experiments for [Ru2-BL]2+ with GMP versus TMP, only GMP selectively coordinated to ruthenium(II). For reactions with calf thymus (CT) DNA, [Ru2-BL]2+ complexes selectively bind to guanine residues of DNA. The higher degrees of binding of [Ru2-BL]2+ to CT-DNA were observed with increasing n values for H2N(CH2)nNH2, which may be explained by the length of the bridging ligands. Studies on the inhibition of the restriction enzyme Acc I revealed that [Ru2-BL]2+ complexes appear to be covalently favorable for the type of difunctional binding. In addition, it is very interesting to observe that circular dichroism spectroscopy of the supernatants obtained following the reactions of CT-DNA with racemic [Ru2-BL]2+ show enrichments of the solutions in the ΔΔ isomers, demonstrating preferences of the ΛΛ isomers for covalent binding to CT-DNA. 相似文献
72.
73.
Yada E Nagata H Noguchi Y Kodera Y Nishimura H Inada Y Matsushima A 《Marine biotechnology (New York, N.Y.)》2005,7(5):474-480
An arginine specific protease, Sp-protease, was purified by column chromatography from freeze-dried Spirulina platensis using a five-step process. Purified Sp-protease has a molecular weight of 80 kDa. It hydrolyzed the synthetic substrates
containing arginine residue in the P1 position but did not hydrolyze synthetic substrates containing other amino acid residues,
including lysine residue in the P1 position. Among the synthetic substrates tested, a substrate of plasminogen activator (Pyr-Gly-Arg-MCA)
was hydrolyzed most effectively with the enzyme (Km = 5.5 × 10−6 M), and fibrin gel was solubilized via activation of intrinsic plasminogen to plasmin with the enzyme. Activity was inhibited
completely with camostat mesilate (Ki = 1.1 × 10−8 M) and leupeptin (Ki = 3.9 × 10−8 M) but was not inhibited with Nα-tosyl-L-lysine chloromethyl ketone (TLCK). The optimum pH of the enzyme has a range of pH 9.0 to pH 11.0. The optimum temperature
was 50°C; the enzyme was stable at 0–50°C. 相似文献
74.
Soichi Kojima Wakako Soga Hiromi Hagiwara Motoyuki Shimonaka Yuji Saito Yuji Inada 《Bioscience reports》1986,6(12):1029-1033
We have succeeded in corroborating the enhancing effect of vitamin A, vitamin C, sitosterol and fucosterol on the fibrinolytic activity of endothelial cells. The assay system consisted of anin situ dissolution of a fibrin layer coated onto a culture dish, over which endothelial cells were grown in a culture medium containing 10 % serum. The dissolution was enhanced by the addition of these vitamins and phytosterols to the culture medium.To whom correspondence should be addressed. 相似文献
75.
76.
Abstract The chloroplast ultrastructure, especially the thylakoid organization, the polypeptide composition of the thylakoid membranes and photosynthetic O2 evolution rate, chlorophyll (Chl) content and Chi a/b ratio were studied in leaves of nine plants growing in contrasting biotopes in the wild in South Finland. All the measurements were made at the beginning of the period of main growth on leaves approaching full expansion, when the CO2-saturated O2 evolution rate (measured at 20°C and 1500 μmol photons m?2s?1) was at a maximum, ranging from 19.2 to 6.9 μmol O2 cm?2 h?1. Among the species, the Chi a/b ratio varied between 3.75 and 2.71. In the mesophyll chloroplasts, the ratio of the total length of appressed to non-appressed thylakoid membranes varied between 1.07 and 1.79, the number of partitions per granum varied between 2.8 and 12.0 and the grana area between 21 and 42% of the chloroplast area. There was a significant relationship between the rate of O2 evolution of the leaf discs and the thylakoid organization in the mesophyll chloroplasts. The higher the O2 evolution rate, the lower was the ratio of the total length of appressed to non-appressed thylakoid membranes and also the lower the grana area. Although the relationship of the photosynthetic rate with the Chi content and the Chi a/b ratio of the leaves was not as clear, a significant negative correlation existed between the Chi a/b ratio and the ratio of appressed to non-appressed thylakoid membranes, indicating lateral heterogeneity in the distribution of different Chl- protein complexes. 相似文献
77.
SUN YOUNG KIM EUN JIN YANG JUN GONG JOONG KI CHOI 《The Journal of eukaryotic microbiology》2010,57(6):460-467
ABSTRACT. The identification of Favella ehrenbergii, a marine planktonic ciliate, has largely been based on its lorica features. This approach is potentially problematic given the polymorphic lorica during this organism's life cycle. We isolated a population of F. ehrenbergii from the coastal waters of Incheon, Korea, and revealed its infraciliature using the protargol staining method. Phylogenetic analysis based on small subunit rRNA gene sequences was also performed. Results showed that this population possessed 16 collar membranelles (CM) and about 100 somatic kineties. These features are highly conserved, even in later dividers. As such, the number of CM and somatic kineties can be used as key characteristics for identification of Favella species. 相似文献
78.
Yutaka Tamaura Katsunobu Takahashi Yoh Kodera Yuji Saito Yuji Inada 《Biotechnology letters》1986,8(12):877-880
Summary A ferromagnetic modifier was prepared by reacting ferrous(Fe2+)- and ferric(Fe3+)-ions with polyethylene glycol having two carboxyl groups (MW:2000) at pH 8.0–8.5. Lipase fromPseudomonas
fragi 22–39B was coupled with the modifier using water-soluble carbodiimide. The modified lipase, which was dispersed into buffered solutions in the size range of 30–70 nm, exerted the hydrolytic activity of 8.0 U/mg. In a magnetic field of 250 Oe, the ferromagnetic-modified lipase was readily recovered from the colloidal solution. 相似文献
79.
80.
Maintenance of neuronal positions in organized ganglia by SAX-7, a Caenorhabditis elegans homologue of L1 下载免费PDF全文
Sasakura H Inada H Kuhara A Fusaoka E Takemoto D Takeuchi K Mori I 《The EMBO journal》2005,24(7):1477-1488
The L1 family of cell adhesion molecules is predominantly expressed in the nervous system. Mutations in human L1 cause neuronal diseases such as HSAS, MASA, and SPG1. Here we show that sax-7 gene encodes an L1 homologue in Caenorhabditis elegans. In sax-7 mutants, the organization of ganglia and positioning of neurons are abnormal in the adult stage, but these abnormalities are not observed in early larval stage. Misplacement of neurons in sax-7 mutants is triggered by mechanical force linked to body movement. Short and long forms of SAX-7 exhibited strong and weak homophilic adhesion activities in in vitro aggregation assay, respectively, which correlated with their different activities in vivo. SAX-7 was localized on plasma membranes of neurons in vivo. Expression of SAX-7 only in a single neuron in sax-7 mutants cell-autonomously restored its normal neuronal position. Expression of SAX-7 in two different head neurons in sax-7 mutants led to the forced attachment of these neurons. We propose that both homophilic and heterophilic interactions of SAX-7 are essential for maintenance of neuronal positions in organized ganglia. 相似文献