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101.
102.
Shohei Yamaoka Yuki Shimono Makoto Shirakawa Yoichiro Fukao Takashi Kawase Noriyuki Hatsugai Kentaro Tamura Tomoo Shimada Ikuko Hara-Nishimura 《The Plant cell》2013,25(8):2958-2969
The adaptor protein-2 (AP-2) complex is a heterotetramer involved in clathrin-mediated endocytosis of cargo proteins from the plasma membrane in animal cells. The homologous genes of AP-2 subunits are present in the genomes of plants; however, their identities and roles in endocytic pathways are not clearly defined in plants. Here, we reveal the molecular composition of the AP-2 complex of Arabidopsis thaliana and its dynamics on the plasma membrane. We identified all of the α-, β-, σ-, and μ-subunits of the AP-2 complex and detected a weak interaction of the AP-2 complex with clathrin heavy chain. The μ-subunit protein fused to green fluorescent protein (AP2M-GFP) was localized to the plasma membrane and to the cytoplasm. Live-cell imaging using a variable-angle epifluorescence microscope revealed that AP2M-GFP transiently forms punctate structures on the plasma membrane. Homozygous ap2m mutant plants exhibited abnormal floral structures, including reduced stamen elongation and delayed anther dehiscence, which led to a failure of pollination and a subsequent reduction of fertility. Our study provides a molecular basis for understanding AP-2–dependent endocytic pathways in plants and their roles in floral organ development and plant reproduction. 相似文献
103.
Kawauchi Hiroshi Kadooka Katuyuki Tanaka Makoto Tuzimura Katura 《Bioscience, biotechnology, and biochemistry》2013,77(11):1720-1726
The separation and identification of fluorescein-thiocarbarnyl (FTC-) amino acid II were accomplished by one- and two-dimensional thin-layer chromatography. The authentic samples for identification of amino acids were synthesized with fluorescein-isothiocyanate II (FITC II) and 21 amino acids. These FTC-amino acids were studied spectrometrically.For quantitative estimation of FTC-amino acids, the fluoroscopy was used. It was found that the fluorescence intensity was proportional to the concentration of FTC-amino acids in 2 pmole/ml to 20 nmole/ml range. Recovery of FTC-derivatives on silica gel plate was about 80%. 相似文献
104.
Soichi Arai Makoto Abe Michiko Yamashita Hiromichi Kato Masao Fujimaki 《Bioscience, biotechnology, and biochemistry》2013,77(4):552-559
An indole derivative having blue fluorescence was produced in cooked soybean digested at 37°C for 24 hr with an acid proteinase Molsin (optimum pH: 2.8) from Aspergillus saitoi or a usual acid proteinase pepsin (optimum pH: 1.6) from beef stomach. This indole derivative was identical with a condensation product from l-tryptophan and n-hexanal. Based on MS, NMR, IR and UV spectrometry, the condensation product was identified as l-pentyl-2, 3, 4, 9-tetrahydro-lH-pyrido [3, 4-b]-indole-3-carboxylic acid [trivial name: 1-pentyl-l, 2, 3, 4-tetrahydro-2-carboline carboxylic acid-(3)].Data were presented of the formation of the above indole derivative and of the resulting consumption of l-tryptophan and n-hexanal.The possible ocurrence of the formation of Harmala alkaloids, i.e. 2-carboline derivatives, through in vitro digestion of soybean with acid proteinases was discussed.A carbonyl-trapping ability of l-tryptophan was suggested. 相似文献
105.
Shin Sato Kin-ichi Nakamura Makoto Tadenuma 《Bioscience, biotechnology, and biochemistry》2013,77(3):308-313
Coloring reaction of sake caused by exposure to sun-light was investigated. There is one of the coloring reactions in which deferri-ferrichrysin participate. The reaction was named Reaction I.Deferri-ferrichrysin, tyrosine, Mn2+ and unknown nitrogenous compound named conveniently compound X were essential for Reaction I and citric acid was stimulative.Compound X was purified by using Amberlite IR 120 (H type) column, active carbon column, silicic acid column and alumina column, and crystallized from methanol-water (1 : 1).The crystals decomposed at 288~290°C. The ultraviolet and infrared spectra of the compound X were essentially identical with those of authentic kynurenic acid.From these results the compound X was identified as kynurenic acid.Since kynurenic acid alone did not cause the color development and riboflavin could be substituted for kynurenic acid in Reaction I, kynurenic acid may act as photosensitizer in Reaction I. 相似文献
106.
Makoto Kiso Hisao Nishiguchi Akira Hasegawa Hiroyuki Okumura Ichiro Azuma 《Bioscience, biotechnology, and biochemistry》2013,77(6):1523-1525
In the initial stage of hydrolysis, exo-ß-(l-→3)-d-glucanase from Basidiomycetes sp. QM 806 cleaved laminaran from Eisenia bicyclis with a pattern resembling an endo-hydrolase. Five kinds of intermediate gluco-oligosaccharides were separated by a combination of gel filtration and HPLC. They were shown to be 32-O-ß-d-glucosyl-gentiobiose, 32-O-ß-d-gentiobiosyl-gentiobiose, 33O-ß-d-glucosyl-gentiotriose, 34-ß-d-glucosyl-32-O-gentiobiosyl-gentiobiose, and 33-O-ß-d-gentio-biosylgentiotriose by enzymic hydrolysis and methylation analysis as well as by 13C NMR spectroscopy. As a result, such kinds of ß-(l → 3)-ß-(l→6)-linked oligosaccharides could be accounted for in the initial cleavage, and they were hydrolyzed ultimately to glucose, gentiobiose, and gentio-triose. It suggests that a single (1 → 3)-linkage on a block of (1 → 6)-links show some resistance to attack by this enzyme. 相似文献
107.
Makoto Shimosaka Yasuki Fukuda Kousaku Murata Akira Kimura 《Bioscience, biotechnology, and biochemistry》2013,77(5):1303-1310
An adenosine-sensitive mutant was isolated from Escherichia coli K12 derivative strain C600. This mutant (designated as PS100) grew slower than parental strain C600in a minimal medium, and its growth was completely inhibited by addition of all kinds of purine bases, nucleosides and nucleotides tested. On the other hand, this growth inhibitory effect of purine derivatives was reversed by co-addition of uridine to the medium. Other pyrimidine derivatives such as uracil, UMP,cytosine, cytidine, CMP and thymidine were also effective for this reversal. The mutant strain, PS100, showed a lower level (7%) of activity for orotate phosphoribosyltransferase than strain C600 did, and accumulated orotic acid in the growth medium. Lysogenization of strain PS100 with λ transducing phage containing the gene for orotate phosphoribosyltransferase (pyrE) resulted in restoration of the activity for orotate phosphoribosyltransferase and removal of growth inhibition by purine derivatives. 相似文献
108.
Phyu Phyu Khine Zar Satoshi Yano Kozue Sakao Fumio Hashimoto Takayuki Nakano Makoto Fujii 《Bioscience, biotechnology, and biochemistry》2013,77(10):1731-1737
Fresh loquat leaves have been used as folk health herb in Asian countries for long time, although the evidence supporting their functions is still minimal. This study aimed to clarify the chemopreventive effect of loquat tea extract (LTE) by investigating the inhibition on proliferation, and underlying mechanisms in human promyelocytic leukemia cells (HL-60). LTE inhibited proliferation of HL-60 in a dose-dependent manner. Molecular data showed that the isolated fraction of LTE induced apoptosis of HL-60 as characterized by DNA fragmentation; activation of caspase-3, -8, and -9; and inactivation of poly(ADP)ribose polymerase. Moreover, LTE fraction increased the ratio of pro-apoptotic Bcl-2-associated X protein (Bax)/anti-apoptotic myeloid cell leukemia 1 (Mcl-1) that caused mitochondrial membrane potential loss and cytochrome c released to cytosol. Thus, our data indicate that LTE might induce apoptosis in HL-60 cells through a mitochondrial dysfunction pathway. These findings enhance our understanding for chemopreventive function of loquat tea. 相似文献
109.