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1.
Molecular and Biochemical Characterization of Three Anthocyanin Synthetic Enzymes from Gentiana triflora 总被引:5,自引:0,他引:5
Tanaka Yoshikazu; Yonekura Keiko; Fukuchi-Mizutani Masako; Fukui Yuko; Fujiwara Hiroyuki; Ashikari Toshihiko; Kusumi Takaaki 《Plant & cell physiology》1996,37(5):711-716
Full length cDNA clones of flavonoid 3',5'-hydroxylase, dihydroflavonol4-reductase and flavonoid 3-glucosyltransferase were clonedfrom petals of Gentiana triflora. Their sequences were homologousto counterparts from other plants. Flavonoid 3',5'-hydroxylaseand flavonoid 3-glucosyltransferase were enzymatically characterizedby expressing cDNAs in heterologous expression systems. (Received May 21, 1996; Accepted June 4, 1996) 相似文献
2.
Plants develop unorganized cell masses like callus and tumors in response to various biotic and abiotic stimuli. Since the historical discovery that the combination of two growth-promoting hormones, auxin and cytokinin, induces callus from plant explants in vitro, this experimental system has been used extensively in both basic research and horticultural applications. The molecular basis of callus formation has long been obscure, but we are finally beginning to understand how unscheduled cell proliferation is suppressed during normal plant development and how genetic and environmental cues override these repressions to induce callus formation. In this review, we will first provide a brief overview of callus development in nature and in vitro and then describe our current knowledge of genetic and epigenetic mechanisms underlying callus formation. 相似文献
3.
Yutaro Yamagata Yukiko Muramoto Sho Miyamoto Keiko Shindo Masahiro Nakano Takeshi Noda 《Microbiology and immunology》2019,63(5):164-171
Defective interfering (DI) influenza viruses carry a large deletion in a gene segment that interferes with the replication of infectious virus; thus, such viruses have potential for antiviral therapy. However, because DI viruses cannot replicate autonomously without the aid of an infectious helper virus, clonal DI virus stocks that are not contaminated with helper virus have not yet been generated. To overcome this problem, we used reverse genetics to generate a clonal DI virus with a PB2 DI gene, amplified the clonal DI virus using a cell line stably expressing the PB2 protein, and confirmed its ability to interfere with infectious virus replication in vitro. Thus, our approach is suitable for obtaining purely clonal DI viruses, will contribute to the understanding of DI virus interference mechanisms and can be used to develop DI virus‐based antivirals. 相似文献
4.
Sakayu Shimizu Keiko Inoue Yoshiki Tani Hideaki Yamada 《Biochemical and biophysical research communications》1981,103(4):1231-1237
The preparation of highly purified medium chain acyl-CoA synthetase (Acid: CoA ligase, AMP-forming (EC 6.2.1.2)) from the cell extracts of is described. The enzyme is inducibly formed in the cells of the microorganism, when it is grown with butyrate as a major carbon source. The purified enzyme is homogeneous on disc gel electrophoresis. Its molecular weight is approximately 142,000, and it is possibly composed of 4 identical subunits of approximately 37,000 molecular weight and has isoelectric point of 4.3. The enzyme catalyzes the stoichiometric conversion of butyrate and CoA to butyryl-CoA in the presence of ATP and Mg2+. It also activates fatty acids with carbon chain lengths of 3 to 5 well, but is inactive toward fatty acids with carbon chain lengths of more than 6. The enzyme is sulfhydryl dependent and inactivated by silver and mercury compounds. 相似文献
5.
Wakae Fujimaki Keiko Baba Katsunori Tatara Ryohji Umezu Sanji Kusakawa Yasushige Mashima 《Human genetics》1987,76(3):302-302
Summary A case of ring chromosome 15 passed on to the index patient's two children is reported, and possible reasons for the infrequent records of inheritance of ring chromosome are suggested. 相似文献
6.
Background
Sequence alignment is one of the most important techniques to analyze biological systems. It is also true that the alignment is not complete and we have to develop it to look for more accurate method. In particular, an alignment for homologous sequences with low sequence similarity is not in satisfactory level. Usual methods for aligning protein sequences in recent years use a measure empirically determined. As an example, a measure is usually defined by a combination of two quantities (1) and (2) below: (1) the sum of substitutions between two residue segments, (2) the sum of gap penalties in insertion/deletion region. Such a measure is determined on the assumption that there is no an intersite correlation on the sequences. In this paper, we improve the alignment by taking the correlation of consecutive residues. 相似文献7.
Guanethidine treatment or adrenal medullectomy significantly inhibited the elevation in blood pressure induced by Clostridium perfringens beta toxin, and the combination of the two drastically reduced the pressure rise, to less than 19% of that in control rats. When rats were pretreated with tetrodotoxin or hexamethonium, the toxin-evoked rise was significantly inhibited. Elevation in blood pressure induced by the toxin in spinal rats tended to be less than that in control rats. When investigated by a microscopical technique, arteriolar constriction in the mesenteric vasculature was observed after the blood pressure elevation induced by the toxin reached a maximum. Blood flow in the skin decreased with an increase in blood pressure following intravenous injection of the toxin. It is concluded that beta toxin acts on the autonomic nervous system and produces arterial constriction. 相似文献
8.
Separation and Determination of cis- and trans- dl-Chrysanthemumic Acid by Gas Liquid Chromatography
Junshi Miyamoto Yoshishige Sato Keiko Awano 《Bioscience, biotechnology, and biochemistry》2013,77(7):1095-1096
Macromolecular synthesis in M. radiodurans after irradiation with the wide range of doses has been investigated in connection with the mechanism for cell killing in radioresistant bacteria. Incorporations of 14C-amino acids into protein and 32Pi into RNA were considerably inhibited by gamma irradiation at higher doses as well as synthesis of DNA. From the results obtained, it is possible to consider that inhibition of RNA and protein synthesis may have an important role in primary events leading to radiation lethality of this radioresistant bacterium. 相似文献
9.
H. Akita Taeko Miyagi Keiko Hata Manabu Kagayama 《Histochemistry and cell biology》1997,107(6):495-503
Histochemical evidence is required to demonstrate the presence of biochemically defined cytosolic sialidase. To meet this
requirement, we examined the immunohistochemical localization of the enzyme in rat skeletal muscles. Sections of chemically
fixed tissues were incubated with a polyclonal antibody raised against a synthetic peptide which corresponded to a part of
the enzyme protein. After incubation with the primary antibody, cryosections for fluorescence microscopy and resin sections
for electron microscopy were incubated with a fluorochrome- and colloidal gold-labeled secondary antibody, respectively. Immunofluorescence
was diffusely distributed in the muscle fibers and was also found in the perimysium and blood vessels. Many immunogold particles
were scattered over the sarcoplasm, myofibrils, nucleoplasm, and matrix of mitochondria. The immunogold particles were also
found in the equivalent compartments of axons, Schwann cells, and cells of endomysium and blood vessels. The specificity of
the primary antibody was elucidated by immunoblotting and an immunoprecipitation test. These findings clearly indicate that
this type of sialidase is essentially located in the cytosolic compartment. Consequently, the name, cytosolic sialidase, will
be appropriate for this enzyme. Additionally it is indicated that this enzyme is also present in cells other than skeletal
muscle fibers.
Accepted: 29 January 1997 相似文献
10.