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91.
92.
Tsujikawa K Kuwayama K Miyaguchi H Kanamori T Iwata Y Inoue H Yoshida T Kishi T 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,852(1-2):430-435
A reliable analytical method was developed for the quantification and identification of muscimol (MUS) and ibotenic acid (IBO), the toxic constituents of Amanita muscaria and Amanita pantherina. MUS and IBO were extracted from mushrooms by aqueous methanol and derivatized with dansyl chloride (DNS-Cl). After extraction with ethyl acetate and evaporation of the solvent, the residue was ethylated with 1.25 M hydrogen chloride in ethanol. The resulting derivatives were quantified by high-performance liquid chromatography with UV detection and identified by liquid chromatography electrospray ionization tandem mass spectrometry. Calibration curves were linear in the range of 25-2500 ppm for MUS and 40-2500 ppm for IBO, respectively. This method was successfully applied to identify and quantify MUS and IBO in Amanita mushrooms naturally grown and circulated in the drug market. 相似文献
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94.
Naohiro Nishikawa Yoshitake Sakae Takuya Gouda Yuichiro Tsujimura Yuko Okamoto 《Biophysical journal》2019,116(5):781-790
A peptide -, which is a fragment from residue 21 to residue 31 of -microgloblin, is experimentally known to self-assemble and form amyloid fibrils. In order to understand the mechanism of amyloid fibril formations, we applied the replica-exchange molecular dynamics method to the system consisting of three fragments of -. From the analyses on the temperature dependence, we found that there is a clear phase transition temperature in which the peptides aggregate with each other. Moreover, we found by the free energy analyses that there are two major stable states: One of them is like amyloid fibrils and the other is amorphous aggregates. 相似文献
95.
Shoichiro Horita Michihiko Kataoka Nahoko Kitamura Takuya Miyakawa Jun Ohtsuka Yuko Maejima 《Bioscience, biotechnology, and biochemistry》2019,83(3):456-462
Old yellow enzymes (OYEs) are potential targets of protein engineering for useful biocatalysts because of their excellent asymmetric reductions of enone compounds. Two OYEs from different yeast strains, Candida macedoniensis AKU4588 OYE (CmOYE) and Pichia sp. AKU4542 OYE (PsOYE), have a sequence identity of 46%, but show different substrate preferences; PsOYE shows 3.4-fold and 39-fold higher catalytic activities than CmOYE toward ketoisophorone and (4S)-phorenol, respectively. To gain insights into structural basis of their different substrate preferences, we have solved a crystal structure of PsOYE, and compared its catalytic site structure with that of CmOYE, revealing the catalytic pocket of PsOYE is wider than that of CmOYE due to different positions of Phe246 (PsOYE)/Phe250 (CmOYE) in static Loop 5. This study shows a significance of 3D structural information to explain the different substrate preferences of yeast OYEs which cannot be understood from their amino acid sequences.
Abbreviations: OYE: Old yellow enzymes, CmOYE: Candida macedoniensis AKU4588 OYE, PsOYE: Pichia sp. AKU4542 OYE 相似文献
96.
Akihiro Kuno Yoshihisa Ikeda Shinya Ayabe Kanako Kato Kotaro Sakamoto Sayaka R. Suzuki Kento Morimoto Arata Wakimoto Natsuki Mikami Miyuki Ishida Natsumi Iki Yuko Hamada Megumi Takemura Yoko Daitoku Yoko Tanimoto Tra Thi Huong Dinh Kazuya Murata Michito Hamada Masafumi Muratani Atsushi Yoshiki Fumihiro Sugiyama Satoru Takahashi Seiya Mizuno 《PLoS biology》2022,20(1)
Genome editing can introduce designed mutations into a target genomic site. Recent research has revealed that it can also induce various unintended events such as structural variations, small indels, and substitutions at, and in some cases, away from the target site. These rearrangements may result in confounding phenotypes in biomedical research samples and cause a concern in clinical or agricultural applications. However, current genotyping methods do not allow a comprehensive analysis of diverse mutations for phasing and mosaic variant detection. Here, we developed a genotyping method with an on-target site analysis software named Determine Allele mutations and Judge Intended genotype by Nanopore sequencer (DAJIN) that can automatically identify and classify both intended and unintended diverse mutations, including point mutations, deletions, inversions, and cis double knock-in at single-nucleotide resolution. Our approach with DAJIN can handle approximately 100 samples under different editing conditions in a single run. With its high versatility, scalability, and convenience, DAJIN-assisted multiplex genotyping may become a new standard for validating genome editing outcomes.Genome editing can introduce designed mutations into a target genomic site, but also into unintended off-target sites. DAJIN, a novel nanopore sequencing data analysis tool, identifies and quantifies allele numbers and their mutation patterns, reporting consensus sequences and visualizing mutations in alleles at single-nucleotide resolution. 相似文献
97.
Tetsuya Hirata Atsushi Kobayashi Tamio Furuse Ikuko Yamada Masaru Tamura Hiroyuki Tomita Yuko Tokoro Akinori Ninomiya Yoshitaka Fujihara Masahito Ikawa Yusuke Maeda Yoshiko Murakami Yasuhiko Kizuka Taroh Kinoshita 《The Journal of biological chemistry》2022,298(3)
Glycosylphosphatidylinositol (GPI) is a posttranslational glycolipid modification of proteins that anchors proteins in lipid rafts on the cell surface. Although some GPI-anchored proteins (GPI-APs), including the prion protein PrPC, have a glycan side chain composed of N-acetylgalactosamine (GalNAc)−galactose−sialic acid on the core structure of GPI glycolipid, in vivo functions of this GPI-GalNAc side chain are largely unresolved. Here, we investigated the physiological and pathological roles of the GPI-GalNAc side chain in vivo by knocking out its initiation enzyme, PGAP4, in mice. We show that Pgap4 mRNA is highly expressed in the brain, particularly in neurons, and mass spectrometry analysis confirmed the loss of the GalNAc side chain in PrPC GPI in PGAP4-KO mouse brains. Furthermore, PGAP4-KO mice exhibited various phenotypes, including an elevated blood alkaline phosphatase level, impaired bone formation, decreased locomotor activity, and impaired memory, despite normal expression levels and lipid raft association of various GPI-APs. Thus, we conclude that the GPI-GalNAc side chain is required for in vivo functions of GPI-APs in mammals, especially in bone and the brain. Moreover, PGAP4-KO mice were more vulnerable to prion diseases and died earlier after intracerebral inoculation of the pathogenic prion strains than wildtype mice, highlighting the protective roles of the GalNAc side chain against prion diseases. 相似文献
98.
Utsumi M Tohno S Minami T Okazaki Y Moriwake Y Yamada M Tohno Y 《Biological trace element research》1999,67(2):165-171
On age relationships of mineral contents in human bones, the contents of the sixth rib and a piece of its compact bone were determined by inductively coupled plasma atomic emission spectrometry (ICPS). The ribs were resected from 21 subjects (14 men and 7 women) who died in age ranging from 65 to 93 yr. There were no age-dependent decreases in Ca and P contents of the ribs in the age range on ICPS. It was found that there were no age-dependent decreases in Ca and P in compact bones of ribs. 相似文献
99.
100.