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71.
72.
Mitsutaka Ogawa Naosuke Nakamura Yoshiaki Nakayama Akira Kurosaka Hiroshi Manya Motoi Kanagawa Tamao Endo Koichi Furukawa Tetsuya Okajima 《Biochemical and biophysical research communications》2013
Hypoglycosylation is a common characteristic of dystroglycanopathy, which is a group of congenital muscular dystrophies. More than ten genes have been implicated in α-dystroglycanopathies that are associated with the defect in the O-mannosylation pathway. One such gene is GTDC2, which was recently reported to encode O-mannose β-1,4-N-acetylglucosaminyltransferase. Here we show that GTDC2 generates CTD110.6 antibody-reactive N-acetylglucosamine (GlcNAc) epitopes on the O-mannosylated α-dystroglycan (α-DG). Using the antibody, we show that mutations of GTDC2 identified in Walker–Warburg syndrome and alanine-substitution of conserved residues between GTDC2 and EGF domain O-GlcNAc transferase resulted in decreased glycosylation. Moreover, GTDC2-modified GlcNAc epitopes are localized in the endoplasmic reticulum (ER). These data suggested that GTDC2 is a novel glycosyltransferase catalyzing GlcNAcylation of O-mannosylated α-DG in the ER. CTD110.6 antibody may be useful to detect a specific form of GlcNAcylated O-mannose and to analyze defective O-glycosylation in α-dystroglycanopathies. 相似文献
73.
74.
Yoshiaki Kitamura Yuki Masegi Shunsuke Ogawa Remi Nakashima Yukihiro Akao Yoshihito Ueno Yukio Kitade 《Bioorganic & medicinal chemistry》2013,21(15):4494-4501
We have developed chemically modified siRNAs and miRNAs bearing urea/thiourea-bridged aromatic compounds at their 3′-end for RNAi therapy. Chemically modified RNAs possessing urea/thiourea-bridged aromatic compounds instead of naturally occurring dinucleotides at the 3′-overhang region were easily prepared in good yields and were more resistant to nucleolytic hydrolysis than unmodified RNA. siRNAs containing urea or thiourea derivatives showed the desired knockdown effect. Furthermore, modified miR-143 duplexes carrying the urea/thiourea compounds in the 3′-end of each strand were able to inhibit the growth of human bladder cancer T24 cells. 相似文献
75.
Humio Kurasawa Yoshiaki Kanauti Koji Takei Shiroshi Ogawa Tetsutaro Okabe Toshiro Hayakawa 《Bioscience, biotechnology, and biochemistry》2013,77(10):1809-1813
A screening was designed to isolate microorganisms having poly(γ-glutamic acid) (PGA) endohydrolase activity. Of the strains screened, TM-4222, from a soil sample, showed the highest viscosity decrement ability on PGA. It was identified to be a Myrothecium sp. The fungal production of the enzyme was slightly promoted with yeast extract and greatly promoted with· both yeast extract and PGA. The fungus was evaluated to produce PGA hydrolase of an endo-type specificity by analyzing of the reaction products. 相似文献
76.
Humio Kurasawa Yoshiaki Kanauchi Tadakatsu Wakayama Toshiro Hayakawa Ikuo Igaue 《Bioscience, biotechnology, and biochemistry》2013,77(12):2913-2916
Varoius piericidin analogues (PS-I, -II and -III in Fig. 2) were synthesized from three 4-acetoxy-6-formylpyridines by Wittig reaction to determine the structure-activity relationships. New type inhibitors, 5-alkenyl-2, 3-dimethoxy-4-hydroxy-6-methylpyridines (PS-IV) were synthesized by intramolecular cyclization. 相似文献
77.
In the course of investigation of alicyclic hydrocarbon-utilizing microorganisms, five strains of ethylcyclohexane-utilizing bacteria were isolated from soil samples.Among those bacteria, the strain S6B1 that was identified as Alcaligenes faecalis, showed the best growth in shaking culture.The strain S6B1 was found to produce 4-ethylcyclohexanol from ethylcyclohexane.This substance separated from culture broth was purified and identified to be trans-4-ethylcyclohexanol by the use of NMR. 相似文献
78.
Yoshiaki Nakahara Masanao Matsui Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(11):2243-2245
A novel synthetic method of 3-substituted furans was developed and syntheses of perillen and dendrolasin are described. 相似文献
79.
Yoshiaki Iwamuro Michiko Murata Koichiro Kanamaru Yoichi Mikami Takuro Kisaki 《Bioscience, biotechnology, and biochemistry》2013,77(2):525-526
The aroL gene, encoding shikimate kinase of Brevibacterium lactofermentum, a coryneform glutamic acid-producing bacterium, was cloned. Recombinant plasmids containing the aroL gene caused elevated levels of shikimate kinase synthesis in B. lactofermentum. It was found that in addition to the aroL gene, the aroB and aroE genes, encoding dehydroquinate synthase and shikimate dehydrogenase, respectively, also existed on these recombinant plasmids, in complementation tests with various Escherichia coli and B. lactofermentum aromatic amino acid auxotrophs. The aroL, aroB and aroE genes of B. lactofermentum are located closely on the cloned DNA fragment, in that order. It was shown that at least these three aro genes form a cluster on the chromosome of B. lactofermentum. 相似文献
80.
Michael J. Miller Yoshito Chikaraishi Nanako O. Ogawa Yoshiaki Yamada Katsumi Tsukamoto Naohiko Ohkouchi 《Biology letters》2013,9(1)
What eel larvae feed on in the surface layer of the ocean has remained mysterious. Gut contents and bulk nitrogen stable isotope studies suggested that these unusual larvae, called leptocephali, feed at a low level in the oceanic food web, whereas other types of evidence have suggested that small zooplankton are eaten. In this study, we determined the nitrogen isotopic composition of amino acids of both natural larvae and laboratory-reared larvae of the Japanese eel to estimate the trophic position (TP) of leptocephali. We observed a mean TP of 2.4 for natural leptocephali, which is consistent with feeding on particulate organic matter (POM) such as marine snow and discarded appendicularian houses containing bacteria, protozoans and other biological materials. The nitrogen isotope enrichment values of the reared larvae confirm that the primary food source of natural larvae is consistent only with POM. This shows that leptocephali feed on readily available particulate material originating from various sources closely linked to ocean primary production and that leptocephali are a previously unrecognized part of oceanic POM cycling. 相似文献