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41.
Ishiguro T Ono T Nakasato K Tsukamoto C Shimada S 《Bioscience, biotechnology, and biochemistry》2003,67(4):752-757
The phytate content in soymilk is known to affect tofu curdling. A rapid measurement of phytate from a water extract of soybean (raw soymilk) in an early stage of tofu processing was investigated using mid-infrared spectroscopy (IR) with an ATR accessory. IR absorption of phytate was observed from 1200 cm-1 to 900 cm-1, and saccharide and protein in the extract also had IR absorption in the same region. In order to separate phytate from other components, the phytate was precipitated completely by the addition of calcium under alkaline condition (pH 11.5). The precipitate was dissolved in citrate buffer (pH 6.0) and then used for IR measurement. The absorbance at 1070 cm-1 correlated well with the phytate content of the soymilk. The measurement of phytate in raw soymilk can be done rapidly by FT-IR measurement with an ATR accessory and gives reproducible values, which can be used for the measurement of phytate content in various soybeans for tofu making. 相似文献
42.
Zhi-Hui Su Osamu Tominaga Takeshi Ohama Eiji Kajiwara Ryoshuke Ishikawa Tokindo S. Okada Keiko Nakamura Syozo Osawa 《Journal of molecular evolution》1996,43(6):662-671
Molecular phylogenetic analyses using mitochondrial NADH dehydrogenase subunit 5 (ND5) gene sequences representing all 15 species and the majority of subspecies or races of theOhomopterus ground beetles from all over the Japanese archipelago have uncovered a remarkable evolutionary history. Clustering of the species in the molecular phylogenetic tree is linked to their geographic distribution and does not correlate with morphological characters. Taxonomically the same species or the members belonging to the same species-group fall out in more than two different places on the ND5 tree. Evidence has been presented against a possible participation of ancestral polymorphism and random lineage sorting or of hybrid individuals for the observed distribution of mitochondrial DNA haplotypes. The most plausible explanation of our results is that parallel evolution took place in different lineages. Most notably,O. dehaanii, O. yaconinus, andO. japonicus in a lineage reveal almost identical morphology with those of the same species (or subspecies) but belonging to the phylogenetically remote lineages.The nucleotide sequence data reported in this paper will appear in the DDBJ, EMBL, and GenBank nucleotide sequence databases with accession numbers D50711-DD-50733 and D87131-D87186. 相似文献
43.
Shigeo Aibara Takahiro Inakuma Yuhei Morita 《Bioscience, biotechnology, and biochemistry》2013,77(11):3051-3052
Penicillium strains (n=394) preserved at NBRC (the NITE Biological Resource Center) were compared as to groupings (11 species-clusters) based on phylogeny and the production of bioactive compounds. The strains in two clusters, of which P. chrysogenum and P. citrinum are representative, showed higher rates of positive strains with multi-biological activities. 相似文献
44.
Ki-Sung Kim Yuichiro Arima Taro Kitazawa Koichi Nishiyama Rieko Asai Yasunobu Uchijima Takahiro Sato Giovanni Levi Sachiko Kitanaka Takashi Igarashi Yukiko Kurihara Hiroki Kurihara 《Mechanisms of development》2013,130(11-12):553-566
Endothelin-1 (Edn1), originally identified as a vasoconstrictor peptide, is involved in the development of cranial/cardiac neural crest-derived tissues and organs. In craniofacial development, Edn1 binds to Endothelin type-A receptor (Ednra) to induce homeobox genes Dlx5/Dlx6 and determines the mandibular identity in the first pharyngeal arch. However, it remains unsolved whether this pathway is also critical for pharyngeal arch artery development to form thoracic arteries. Here, we show that the Edn1/Ednra signaling is involved in pharyngeal artery development by controlling the fate of neural crest cells through a Dlx5/Dlx6-independent mechanism. Edn1 and Ednra knock-out mice demonstrate abnormalities in pharyngeal arch artery patterning, which include persistent first and second pharyngeal arteries, resulting in additional branches from common carotid arteries. Neural crest cell labeling with Wnt1-Cre transgene and immunostaining for smooth muscle cell markers revealed that neural crest cells abnormally differentiate into smooth muscle cells at the first and second pharyngeal arteries of Ednra knock-out embryos. By contrast, Dlx5/Dlx6 knockout little affect the development of pharyngeal arch arteries and coronary arteries, the latter of which is also contributed by neural crest cells through an Edn-dependent mechanism. These findings indicate that the Edn1/Ednra signaling regulates neural crest differentiation to ensure the proper patterning of pharyngeal arch arteries, which is independent of the regional identification of the pharyngeal arches along the dorsoventral axis mediated by Dlx5/Dlx6. 相似文献
45.
Masaki Honda Tatsuya Kudo Takahiro Kuwa Takuma Higashiura Tetsuya Fukaya Yoshinori Inoue 《Bioscience, biotechnology, and biochemistry》2017,81(2):365-371
Lycopene has a large number of geometric isomers caused by E/Z isomerization at arbitrary sites within the 11 conjugated double bonds, offering varying characteristics related to features such as antioxidant capacity and bioavailability. However, the geometric structures of only a few lycopene Z-isomers have been thoroughly identified from natural sources. In this study, seven multi-Z-isomers of lycopene, (9Z,13′Z)-, (5Z,13Z,9′Z)-, (9Z,9′Z)-, (5Z,13′Z)-, (5Z,9′Z)-, (5Z,9Z,5′Z)-, and (5Z,9Z)-lycopene, were obtained from tomato samples by thermal isomerization, and then isolated by elaborate chromatography, and fully assigned using proton nuclear magnetic resonance. Moreover, the theoretically preferred pathway from (all-E)-lycopene to di-Z-isomers was examined with a computational approach using a Gaussian program. Fine-tuning of the HPLC separation conditions led to the discovery of novel multi-Z-isomers, and whose formation was supported by advanced theoretical calculations. 相似文献
46.
Arikuni Uchimura Yuko Hidaka Takahiro Hirabayashi Masumi Hirabayashi Takeshi Yagi 《PloS one》2009,4(1)
Background
In eukaryotic cells, DNA polymerase δ (Polδ), whose catalytic subunit p125 is encoded in the Pold1 gene, plays a central role in chromosomal DNA replication, repair, and recombination. However, the physiological role of the Polδ in mammalian development has not been thoroughly investigated.Methodology/Principal Findings
To examine this role, we used a gene targeting strategy to generate two kinds of Pold1 mutant mice: Polδ-null (Pold1 −/−) mice and D400A exchanged Polδ (Pold1 exo/exo) mice. The D400A exchange caused deficient 3′–5′ exonuclease activity in the Polδ protein. In Polδ-null mice, heterozygous mice developed normally despite a reduction in Pold1 protein quantity. In contrast, homozygous Pold1 −/− mice suffered from peri-implantation lethality. Although Pold1 −/− blastocysts appeared normal, their in vitro culture showed defects in outgrowth proliferation and DNA synthesis and frequent spontaneous apoptosis, indicating Polδ participates in DNA replication during mouse embryogenesis. In Pold1 exo/exo mice, although heterozygous Pold1 exo/+ mice were normal and healthy, Pold1 exo/exo and Pold1 exo/− mice suffered from tumorigenesis.Conclusions
These results clearly demonstrate that DNA polymerase δ is essential for mammalian early embryogenesis and that the 3′–5′ exonuclease activity of DNA polymerase δ is dispensable for normal development but necessary to suppress tumorigenesis. 相似文献47.
Y Takahashi T Koyanagi Y Suzuki Y Saga N Kanomata T Moriya M Suzuki Y Sato 《Molecular cancer research : MCR》2012,10(9):1135-1146
Vasohibin-1 (VASH1) is a VEGF-inducible endothelium-derived angiogenesis inhibitor and VASH2 is its homolog. Our previous analysis revealed that VASH1 is expressed in endothelial cells to terminate angiogenesis, whereas VASH2 is expressed in infiltrating mononuclear cells mobilized from bone marrow to promote angiogenesis in a mouse model of hypoxia-induced subcutaneous angiogenesis. To test the possible involvement of VASH2 in the tumor, we examined human ovarian cancer cells for the presence of VASH2. Immunohistochemical analysis revealed that VASH2 protein was preferentially detected in cancer cells of serous ovarian adenocarcinoma. We then used SKOV-3 and DISS, two representative human serous adenocarcinoma cell lines, and examined the role of VASH2 in the tumor. The knockdown of VASH2 showed little effect on the proliferation of cancer cells in vitro but notably inhibited tumor growth, peritoneal dissemination, and tumor angiogenesis in a murine xenograft model. Next, we stably transfected the human VASH2 gene into two types of murine tumor cells, EL-4 and MLTC-1, in which endogenous VASH2 was absent. When either EL-4 or MLTC-1 cells were inoculated into VASH2 (-/-) mice, the VASH2 transfectants formed bigger tumors when compared with the controls, and the tumor microvessel density was significantly increased. VASH2 stimulated the migration of endothelial cells, and its increased expression in cancer cells is related to the decrease of mir-200b. These results indicate that VASH2 expressed in serous ovarian carcinoma cells promoted tumor growth and peritoneal dissemination by promoting angiogenesis. Mol Cancer Res; 10(9); 1135-46. ?2012 AACR. 相似文献
48.
Sato T Nakamura Y Shiimura Y Ohgusu H Kangawa K Kojima M 《Journal of biochemistry》2012,151(2):119-128
Ghrelin is a stomach hormone that acts as an endogenous ligand of orphan G-protein-coupled receptor. Ghrelin is a 28-amino acid peptide existing in two major forms: n-octanoyl-modified ghrelin, which possesses an n-octanoyl modification on serine-3 and des-acyl ghrelin. Fatty acid modification of ghrelin is essential for ghrelin-induced growth hormone release from the pituitary and appetite stimulation. This acyl-modification of ghrelin is catalysed by ghrelin-O-acyl transferase recently identified. Despite the number of innovative advancements in this field of research, there are still many aspects of ghrelin function and biosynthesis process that remain to be clarified. Here, we review the current understanding of the structure, regulation and function of ghrelin; this review is intended for researchers who will be involved in this field in the future. 相似文献
49.
Daisuke Yamane-Koshizawa Sotaro Fujii Takahiro Maruno Yuji Kobayashi Masaru Yamanaka Satoshi Wakai 《Bioscience, biotechnology, and biochemistry》2018,82(2):304-311
AVCP cytochrome c′ from mesophilic Allochromatium vinosum exhibits lower stability than a thermophilic counterpart, Hydrogenophilus thermoluteolus cytochrome c′ (PHCP), in which the six specific amino acid residues that are not conserved in AVCP are responsible for its stability. Here we measured the stability of AVCP variants carrying these specific residues instead of the original AVCP ones. Among the six single AVCP variants, all of which formed a dimeric structure similar to that of the wild-type, three were successfully stabilized compared with the wild-type, while one showed lower stability than the wild-type. In addition, the most stabilized and destabilized AVCP variants could bind CO, similar to the wild-type. These results indicated that mesophilic AVCP could be stabilized through specific three mutations modeled by the thermophilic counterpart, PHCP, without changing the CO binding ability. 相似文献
50.
Ikuko Kusaba Takahiro Nakao Hiroko Maita Shusei Sato Ryota Chijiiwa Emi Yamada Susumu Arima Mareshige Kojoma Kanji Ishimaru Ryo Akashi Akihiro Suzuki 《Plant Biotechnology》2021,38(1):57
Licorice (Glycyrrhiza uralensis) is a medicinal plant that contains glycyrrhizin (GL), which has various pharmacological activities. Because licorice is a legume, it can establish a symbiotic relationship with nitrogen-fixing rhizobial bacteria. However, the effect of this symbiosis on GL production is unknown. Rhizobia were isolated from root nodules of Glycyrrhiza glabra, and a rhizobium that can form root nodules in G. uralensis was selected. Whole-genome analysis revealed a single circular chromosome of 6.7 Mbp. This rhizobium was classified as Mesorhizobium by phylogenetic analysis and was designated Mesorhizobium sp. J8. When G. uralensis plants grown from cuttings were inoculated with J8, root nodules formed. Shoot biomass and SPAD values of inoculated plants were significantly higher than those of uninoculated controls, and the GL content of the roots was 3.2 times that of controls. Because uninoculated plants from cuttings showed slight nodule formation, we grew plants from seeds in plant boxes filled with sterilized vermiculite, inoculated half of the seedlings with J8, and grew them with or without 100 µM KNO3. The SPAD values of inoculated plants were significantly higher than those of uninoculated plants. Furthermore, the expression level of the CYP88D6 gene, which is a marker of GL synthesis, was 2.5 times higher than in inoculated plants. These results indicate that rhizobial symbiosis promotes both biomass and GL production in G. uralensis. 相似文献