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1.
The defatted sclerotia powder was partially hydrolyzed with dilute acid, and the material obtained was fractionated by carbon column chromatography, separated into two disaccharides, three trisaccharides and three tetrasaccharides, respectively. In these hydrolyzates α, α-trehalose, Iaminaribiose, and gentiobiose were identified. 相似文献
2.
Identification of heterogeneous and microheterogeneous subunits of glutathione S-transferase in rat liver cytosol 总被引:3,自引:0,他引:3
Subunits of multiple molecular forms of dimeric glutathione S-transferase in rat liver cytosol were analyzed by two-dimensional gel electrophoresis (isoelectric focusing/sodium dodecyl sulfate-electrophoresis) followed by staining with Coomassie blue dye. The five subunits, Ya, Yb, Yb', Yc, and Yp (Mr's 26,500, 27,500, 27,500, 28,500, and 26,000, respectively) of seven molecular forms, A2, AC, C2, B2, BL, L2, and GST-P, were identified by comparison of molecular weights and pI values with those of purified molecular forms and by immunoadsorption of the molecular forms in the cytosol as well as those synthesized in vitro using antibodies against the seven forms. Yp is the subunit of placental glutathione S-transferase, GST-P (YpYp), which is markedly increased in carcinogen-treated rat livers [A. Kitahara et al. (1984) Cancer Res. 44, 2698-2703; K. Satoh et al. (1985) Proc. Natl. Acad. Sci. USA 82, 3964-3968]. Microheterogeneity was detectable within Yb, Yb', and Yp subunits, the different forms, termed Yb1, Yb2, Yb'1, Yb'2, and Yp1, Yp2, being similar in size but differing by approx. 0.3 pI unit within each subunit. These microheterogeneous forms were also detectable in the polypeptides translated in vitro in a rabbit reticulocyte lysate translation system from liver poly(A)-containing RNAs, suggesting that they are translatable from distinct mRNAs. 相似文献
3.
As a quantitative approach to the life histories of fishes, the present paper attempted to predict a relation among reproduction, growth and mortality numerically with a technique of control theory, the discrete maximum principle. A method for predicting the relation was derived on the postulate that natural selection maximized the net reproductive rate subject to a few constraints. The derived method was applied to Atlantic cod and Atlantic herring populations in the Southern Gulf of St. Lawrence as numerical examples. The examples demonstrated that the theoretical reproductive effort and body weight were well consistent with the observed ones every age but the theoretical survival rates were slightly different from the observed ones. For the reasons mentioned below, however, it should be interpreted that the examples rather support the adopted postulate to a certain degree. First, in general, it is very difficult to obtain good estimates of the rates with traditional methods. Second, intense fishing pressure possibly changes the life history parameters to some extent in fish populations. Moreover, the examples also suggested that, to examine the postulate in further detail, similar analyses had to be made with the data of many fish populations on which intense fishing pressure had not been exerted. 相似文献
4.
5.
A novel photoaffinity ligand for the phencyclidine site of the N-methyl-D-aspartate receptor labels a Mr 120,000 polypeptide 总被引:2,自引:0,他引:2
M S Sonders P Barmettler J A Lee Y Kitahara J F Keana E Weber 《The Journal of biological chemistry》1990,265(12):6776-6781
A radiolabeled photoaffinity ligand has been developed for the N-methyl-D-aspartate (NMDA)-preferring excitatory amino acid receptor complex. [3H]3-Azido-(5S, 10R)(+)-5-methyl-10,11-dihydro-5H- dibenzo[a,d]cyclohepten-5,10-imine [3H]3-azido-MK-801 demonstrated nearly identical affinity, density of binding sites, selectivity, pH sensitivity, and pharmacological profile in reversible binding assays with guinea pig brain homogenates to those displayed by its parent compound, MK-801. When employed in a photo-labeling protocol designed to optimize specific incorporation, [3H]3-azido-MK-801 labeled a single protein band which migrated in sodium dodecyl sulfate-polyacrylamide gels with Mr = 120,000. Incorporation of tritium into this band was completely inhibited when homogenates and [3H]3-azido-MK-801 were coincubated with 10 microM phencyclidine. These data suggest that the phencyclidine site of the NMDA receptor complex is at least in part comprised of a Mr = 120,000 polypeptide. 相似文献
6.
Koichi Suzuki Misa Iwata Shigenori Ito Kiyoshi Matsui Atsuko Uchida Yasuhiko Mizoi 《Human genetics》1994,94(2):129-135
The “a” subunit of human coagulation factor XIII (F13A) exhibits genetic polymorphism defined by four common alleles, F13A*1A, *1B, *2A, and *2B. We have previously suggested on the basis of the isoelectric focusing patterns of the four allele products that point mutations at two separate sites and one intragenic crossing over might be involved in the genes of F13A polymorphism. Here, we report nucleotide substitutions associated with F13A polymorphism. A C/T transition of the second nucelotide of codon 564 in exon 12 is responsible for the difference between F13A*1A and *1B and that between F13A*2A and *2B, and a set of two base changes in codons 650 and 651 in exon 14 leads to the differences between F13A*1A and *2A and those between F13A*1B and *2B. The four combinations of the point mutations at the two exons thus correspond to the four alleles, two of which were generated by the point mutations from ancestral monomorphic gene. The results suggest strongly that intragenic crossing over must be involved in the genesis of the fourth allele. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods discriminating these base changes in exons 12 and 14 are also presented. 相似文献
7.
Kohei Irifune Kanji Ono Misa Takahashi Hideko Murakami Hiromichi Morikawa 《Transgenic research》1996,5(5):337-341
Suspension-cultured cells (A-18 line) of the liverwortMarchanta polymorpha were bombarded by a pneumatic particle gun with plasmid pCH harbouring the hygromycin phosphotransferase (HPT) gene (hpt) under the control of the cauliflower mosaic virus (CaMV) 35 S promoter and the nopaline synthase polyadenylation region. Nine weeks after bombardments, 128 hygromycin-resistant calluses were obtained from an approximate total of 7×106 cells. Ten cell lines chosen randomly were analysed further. Southern blot analysis showed that all of the ten lines contain thehpt gene in the genome, demonstrating that these lines are transformants. An HPT enzyme activity assay confirmed the expression of the gene in all of the transformant lines. 相似文献
8.
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
9.
(+)-Abscisic acid was isolated as the methyl ester from Pinus densiflora pollen and identified spectroscopically. 相似文献
10.
Solvent-extractable lipids in Pinus densiflora pollen were investigated. The cis- and trans-isomers of 1,16-dioxo-, 1-hydroxy-16-oxo- and 1, 16-dihydroxyhexadecan-7-yl p-coumarates were identified. 相似文献