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141.
Cell protein isolates were prepared from yeast (S. cerevisiae) by alkali-extraction followed by acid precipitation. The relationships between alkali-treatment and nucleic acid contents in cell protein isolates were examined.The isolate which was precipitated at pH 4.5 following extraction with 0.20 n NaOH at 80°C contained small amounts (less than 1 % of the isolate) of nucleic acids. However, the content of nucleotides in the isolate which was precipitated at pH 4.5 following extraction with 0.20 n NaOH at 37°C was 9.13% of the product. Treatment by washing or dialysis of the isolate had little effect in removing the nucleotides in the isolate.This finding was explained by the interaction of nucleotide to cell protein isolate. The binding energy was measured by Hummel’s method. 相似文献
142.
Masaaki Yoshikawa Etsuro Sugimoto Hideo Chiba 《Bioscience, biotechnology, and biochemistry》2013,77(5):1005-1013
It was indicated from ultraviolet difference spectra and ultracentrifugal experiments that associations occurred between two casein components (αs- and κ-caseins, β- and κ-caseins and αs- and β-caseins) at lower CaCl2 concentrations (2~3 mm) and that aromatic amino acid residues participated in the associations. Chemical modification studies with 2-hydroxy-5-nitrobenzylbromide indicated that tryptophane residues of each casein component were not essential for these associations. It was also demonstrated by nitration of tyrosine residues with tetranitromethane that tyrosine residues of κ-casein were essential for αs·κ-association and for β·κ-association and that tyrosine residues of αs-casein were important to αs·β-association.Interactions between casein components were also studied at higher CaCl2 concentration (10 mm) which is enough for micelle formation. It was found that tyrosine residues of κ- casein played an important role for the stabilization of αs- and β-caseins. Properties of the nitrated-β-casein were almost the same as that of the native β-casein except the absorption spectrum. αs·β-Interaction in the presence of 10 mm CaCl2 was investigated by use of the nitrated-β-casein instead of the native β-casein. It was proved that αs-casein was stabilized by the nitrated-β-casein and that precipitation of the nitrated-β-casein increased in the presence of αs-casein.The mechanism of interactions between casein components at higher CaCl2 concentration (10 mm) are discussed in connection with the associations at lower CaCl2 concentrations (2~3 mm). 相似文献
143.
Shizuko Yamaguchi Tomoko Yoshikawa Shingo Ikeda Tsunehiko Ninomiya 《Bioscience, biotechnology, and biochemistry》2013,77(7):797-802
Taste effects of six newly synthesized ribonucleotide derivatives, i.e., disodium salts of 2-methyl-5′-inosinic acid · 6H2O, 2-ethyl-5′-inosinic acid · 1.5H2O, 2-N-methyl-5′-guanylic acid · 5.5H2O, 2-N-dimethyl-5′-guanylic acid · 2.5H2O, 2-methylthio-5′-inosinic acid · 6H2O and 2-ethylthio-5′-inosinic acid · 2H2O, were studied. Stimulus thresholds (detection thresholds) of these derivatives ranged from about 0.02 to 0.006 g/100ml. Flavor-enhancing activities of them were 2.3 to 8.0 times larger than that of disodium 5′-inosinate · 7.5H2O IMP) in the synergistic effect with monosodium glutamate. Furthermore, the quality of taste of all the derivatives was recognized to be the same kind to that of IMP. 相似文献
144.
Mika Takai Yoshiyuki Miyazaki Hirofumi Tachibana 《Bioscience, biotechnology, and biochemistry》2013,77(10):1743-1747
In this study, we revealed that a Mekabu (Udaria pinnantifida) extract enhanced immunoglobulin (Ig) production of mouse spleen lymphocytes. Furthermore, it was suggested that water-soluble and high molecular weight ingredients in the Mekabu extract have significant enhancing effect on Ig production. Therefore, fucoidan was estimated as the active component. 相似文献
145.
Hirofumi Sakoguchi Tomoya Shintani Hironobu Ishiyama Ryo C. Yanagita Yasuhiro Kawanami 《Bioscience, biotechnology, and biochemistry》2013,77(12):2194-2197
ABSTRACTThe nematocidal activities of the fatty acid esters of d-allose were examined using the larvae of C. elegans. Among the fatty acid esters, 6-O-octanoyl-d-allose (3) showed significant activity. 6-O-octanoyl-d-glucose (5) showed no activity, indicating that the D-allose moiety is essential for the nematocidal activity of 3. A nonhydrolyzable alkoxy analog 6-O-octyl-d-allose (6) also showed activity equivalent to that of 3. 相似文献
146.
Satoshi Fujita Jaromir Pytela Takashi Hotta Takehide Kato Takahiro Hamada Rie Akamatsu Yasumasa Ishida Natsumaro Kutsuna Seiichiro Hasezawa Yuko Nomura Hirofumi Nakagami Takashi Hashimoto 《Current biology : CB》2013,23(20):1969-1978
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147.
Hitomi Yatsuki Ken Higashimoto Kosuke Jozaki Kayoko Koide Junichiro Okada Yoriko Watanabe Nobuhiko Okamoto Yoshinobu Tsuno Yoko Yoshida Kazutoshi Ueda Kenji Shimizu Hirofumi Ohashi Tsunehiro Mukai Hidenobu Soejima 《Genes & genomics.》2013,35(2):141-147
Beckwith-Wiedemann syndrome (BWS) is an imprinting-related human disease that is characterized by macrosomia, macroglossia, abdominal wall defects, and variable minor features. BWS is caused by several genetic/epigenetic alterations, such as loss of methylation at KvDMR1, gain of methylation at H19-DMR, paternal uniparental disomy of chromosome 11, CDKN1C mutations, and structural abnormalities of chromosome 11. CDKN1C is an imprinted gene with maternal preferential expression, encoding for a cyclin-dependent kinase (CDK) inhibitor. Mutations in CDKN1C are found in 40 % of familial BWS cases with dominant maternal transmission and in ~5 % of sporadic cases. In this study, we searched for CDKN1C mutations in 37 BWS cases that had no evidence for other alterations. We found five mutations—four novel and one known—from a total of six patients. Four were maternally inherited and one was a de novo mutation. Two frame-shift mutations and one nonsense mutation abolished the QT domain, containing a PCNA-binding domain and a nuclear localization signal. Two missense mutations occurred in the CDK inhibitory domain, diminishing its inhibitory function. The above-mentioned mutations were predicted by in silico analysis to lead to loss of function; therefore, we strongly suspect that such anomalies are causative in the etiology of BWS. 相似文献
148.
Small G proteins of the Rho family are pivotal regulators of several signaling networks. The Ras homolog family (Rho) and one of its targets, Rho-associated protein kinase (ROCK), participate in a wide variety of biological processes, including bone formation. A previous study has demonstrated that the ROCK inhibitor Y-27632 enhanced bone formation induced by recombinant human bone morphogenetic protein-2 (BMP-2) in vivo and in vitro. However, the effect of other Rho family members, such as Ras-related C3 botulinum toxin substrate 1 (Rac1) and cell division cycle 42 (Cdc42), on bone formation remains unknown. In this study, we investigated whether Rac1 also participates in BMP-2-induced osteogenesis. Expression of a dominant-negative mutant of Rac1 enhanced BMP-2-induced osteoblastic differentiation in C2C12 cells, whereas a constitutively active mutant of Rac1 attenuated that effect. Knockdown of T-lymphoma invasion and metastasis 1 (Tiam1), a Rac-specific guanine nucleotide exchange factor, enhanced BMP-2-induced alkaline phosphatase activity. Further, we demonstrated that BMP-2 stimulated Rac1 activity. These results indicate that the activation of Rac1 attenuates osteoblastic differentiation in C2C12 cells. 相似文献
149.
Yusuke K. Kawai Kensuke P. Watanabe Akihiro Ishii Aiko Ohnuma Hirofumi Sawa Yoshinori Ikenaka Mayumi Ishizuka 《Comparative biochemistry and physiology. Part D, Genomics & proteomics》2013,8(3):201-208
The cytochrome P450 (CYP) 1–3 families are involved in xenobiotic metabolism, and are expressed primarily in the liver. Ostriches (Struthio camelus) are members of Palaeognathae with the earliest divergence from other bird lineages. An understanding of genes coding for ostrich xenobiotic metabolizing enzyme contributes to knowledge regarding the xenobiotic metabolisms of other Palaeognathae birds. We investigated CYP1–3 genes expressed in female ostrich liver using a next-generation sequencer. We detected 10 CYP genes: CYP1A5, CYP2C23, CYP2C45, CYP2D49, CYP2G19, CYP2W2, CYP2AC1, CYP2AC2, CYP2AF1, and CYP3A37. We compared the gene expression levels of CYP1A5, CYP2C23, CYP2C45, CYP2D49, CYP2G19, CYP2AF1, and CYP3A37 in ostrich liver and determined that CYP2G19 exhibited the highest expression level. The mRNA expression level of CYP2G19 was approximately 2–10 times higher than those of other CYP genes. The other CYP genes displayed similar expression levels. Our results suggest that CYP2G19, which has not been a focus of previous bird studies, has an important role in ostrich xenobiotic metabolism. 相似文献
150.
Kazuma?Takahashi Takashi?Kondo Yasunaga?Yoshikawa Kiyotaka?Watanabe Koichi?OrinoEmail author 《Acta veterinaria Scandinavica》2013,55(1):70