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51.
Masahiko Maekawa Megumu Munakata Takayoshi Kuroda-Sowa Koji Hachiya 《Inorganica chimica acta》1995,230(1-2):249-252
A novel hexanickel(II) complex [Ni6(NCCHCH2CH2CHCN)6] (2) with 1,4-dicyanobutane-1,4-diyl (L) which was produced by the metal-induced dimerization of acrylonitrile (AN) has been isolated and the structure has been determined crystallographically. Complex 2 is triclinic, space group . Each nickel atom is coordinated by two carbon atoms of L and two nitrogen atoms of the cyano group of two other L, providing a square-plenar geometry. The six nickel atoms are bridged by the cyano group and carbon atom to form the slightly distorted octahedral Ni6 core. 相似文献
52.
Mitsuyo Okazaki Makoto Kinoshita Chikayuki Naito Ichiro Hara 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1984,336(1)
A simple and rapid method for apolipoprotein analysis in serum high-density lipoproteins (HDL) has been developed using high-performance liquid chromatography (HPLC) with sodium phosphate buffer (pH 7.0) containing 0.1% sodium dodecyl sulphate (SDS) as eluent. In contrast to the use of urea solution as an eluent, apolipoproteins can be analysed by applying an incubation mixure of HDL and the eluent buffer. A TSK-GEL column of G3000SW was found to be more profitable than G2000SW or G4000SW for analysis of HDL apolipoproteins. Elution patterns monitored by absorbance at 280 nm using a G3000SW column can give precise quantitative as well as qualitative information about apolipoproteins of molecular weight between 104 and 105. HPLC patterns of HDL apolipoproteins were compared between individual human subjects with various diseases. Elution profiles for lipid components in an incubation mixture were also examined. 相似文献
53.
Abstract A lignin substructure model, 1-(4-ethoxy-3,5-dimethoxyphenyl)-2-(4-ethoxy-3-methoxyphenyl)-propane-1,3-diol(I), was actively metabolized by a white-rot fungus Coriolus versicolor in low nitrogen stationary cultures favouring the ligninolytic activity in the fungus. Cleavage of the dimer I between Cα and Cβ of the propanoid side chain was the major degradative reaction by the fungus. 相似文献
54.
55.
U Sankawa M Shibuya Y Ebizuka H Noguchi T Kinoshita Y Iitaka A Endo N Kitahara 《Prostaglandins》1982,24(1):21-34
Forty depsides and depsidones, the esters of phenolcarboxylic acids, were examined for their inhibitory effect against prostaglandin biosynthesis with rabbit renal microsomes. 4-0-Methylcryptochlorophaeic acid was the most active inhibitor so far tested and its IC50 value was 0.34 muM. Kinetic investigation has shown that this depside acts competitively with respect to arachidonic acid as most of the non - steroidal antiinflammatory drugs. X-Ray analysis has revealed that 4-0-methylcryptochlorophaeic acid maintains its rigid conformation by forming a strong hydrogen bond between the hydroxyl and methoxyl groups. Comparison of CPK models between 4-0-methylcryptochlorophaeic acid and non-steroidal antiinflammatory drugs revealed that the carboxyl group and the two rings of these drugs are almost superimposable to those of the depside. This finding led us to propose a new active site model based on the three dimentional structure of the depside. 相似文献
56.
An anticomplementary agent, K-76 monocarboxylic acid: its site and mechanism of inhibition of the complement activation cascade. 总被引:11,自引:0,他引:11
K Hong T Kinoshita W Miyazaki T Izawa K Inoue 《Journal of immunology (Baltimore, Md. : 1950)》1979,122(6):2418-2423
A monocarboxylic acid derivative (K-76 COOH) of K-76, purified from the culture filtrate of Stachybotrys complement I nov. sp. K-76, inhibits complement (C) activity. Its inhibitory action is mainly on C5 step. It strongly inhibits the generation of EAC1,4b,2a,3b,5b from C5 and EAC1,4b,2a,3b, and accelerates the decay of EAC1,4b,2a,3b,5b. It also causes some inhibition of the reactions of the reactions of C2,C3,C6,C7 and C9 with their respective preceding intermediate cells. It has no effect on the generation of EAC1,4b from C4 and EAC1, or of EAC-8 from C8 and EAC-7, and apparently increases the generation of EAC1,4b from C1 and EAC4b probably by inhibiting transfer or turnover of C1. It does not affect the rate of decay of EAC1,4b,2a or the T max of generation of EAC1,4b,2a, and it inhibits immune adherence only at high concentration. K-76 COOH also strongly inhibits hemolysis through the alternative pathway of C activation by cobra venom factor, but it does not seem to inhibit the early steps of the alternative pathway, because it has little affect on the consumption of C3 or the conversion of beta 1C to beta 1A on treatment of C serum with zymosan. K-76 COOH probably combines with C5 molecules, forming the inactive complexes, or it causes the structural alteration of C5. 相似文献
57.
Takayoshi Shotake Yoshiko Ohkura Goichi Ishimoto 《Primates; journal of primatology》1977,18(2):285-290
The electrophoretic variations of erythrocyte phosphohexose isomerase (PHI) were examined in 1433 blood samples from 37 troops
of Japanese macaques in order to clarify the gene dynamics of this species. The genetic polymorphisms were observed in several
troops. The troops showing the variation of PHI were Fukushima, Shiga A, Shiga C, Ryozenyama, Mikata I and II, Kawara, Takasakiyama
A, B, and C, Itsuki, Koshima and Kushima. The variant alleles found in these troops were PHI
2
mac
, PHI
7
mac
, PHI
8
mac
, and PHI
10
mac
alleles, and the PHI
10
mac
allele was newly found in the present work. 相似文献
58.
Microbial Production of Ursodeoxycholic Acid from Lithocholic Acid by Fusarium equiseti M41 总被引:2,自引:2,他引:0
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Haruji Sawada Songsri Kulprecha Naline Nilubol Toshiomi Yoshida Shinichi Kinoshita Hisaharu Taguchi 《Applied microbiology》1982,44(6):1249-1252
A fungus identified as Fusarium equiseti was isolated from soil and found to carry out 7β-hydroxylation of lithocholic acid to ursodeoxycholic acid (35% yield; 350 mg/liter) in 112 h. 相似文献
59.
Crystallization and main-chain structure of neutral protease from Streptomyces caespitosus 总被引:1,自引:0,他引:1
A neutral protease, i.e., a zinc-containing metalloendoprotease from Streptomyces caespitosus, has been crystallized using acetone as a precipitating agent. The crystals diffract to better than 1.5 A resolution when a rotating anode X-ray generator is used as an X-ray source. Protein phase angles were calculated by the multiple isomorphous replacement method using two heavy-atom derivatives (HgCl2 and CH3HgCl). A 6 A resolution electron density map clearly showed molecular boundaries. Although its amino acid sequence is not known, the folding pattern of the polypeptide chain could be traced on a 2.5 A resolution electron density map. A large cleft, which is located on the molecular surface, was proved to be the active site of the enzyme by structure analyses of inhibitor-complex crystals. The highest electron density peak, which corresponds to the cleft, was assigned to a catalytically essential zinc atom on difference Fourier synthesis between native and EDTA-soaked crystals. 相似文献
60.
M Kawaichi C Oka R Reeves M Kinoshita T Honjo 《The Journal of biological chemistry》1991,266(27):18387-18394
We have constructed a plasmid, pLTR100, which contains human interleukin 2 receptor light (IL-2R L) chain cDNA in the inverted orientation relative to the upstream SV40 promoter. The cDNA segment is flanked by the immunoglobulin gene recombination signal sequences so that the cDNA segment can invert and the human IL-2R L chain is subsequently expressed under the control of the SV40 promoter. A murine pre-B cell line, 38B9, transfected with pLTR100 began to express the human IL-2R L chain on the cell surface. The frequency of human IL-2R L chain positive cells increased almost linearly up to 50% for 60 days of culture after transfection. Southern blot analysis and sequencing of the DNA fragments at the recombination junction confirmed that the cDNA segment was inverted in a signal sequence-dependent manner by the variable-diversity-joining recombination process. Transgenic mice bearing the recombination substrate DNA similar to pLTR100 expressed the human IL-2 L chain in the spleen, thymus, and bone marrow, but not in the other tissues examined at the detectable level. Both IgM- and CD3-positive cells expressed the human IL-2R L chain, indicating that this artificial DNA can serve as a substrate for recombination both in B- and T-cells and that another DNA segment may be necessary to confer the cell-type specificity on the substrate DNA. 相似文献