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91.
Yasuo Kitagawa Etsuro Sugimoto Hideo Chiba 《Bioscience, biotechnology, and biochemistry》2013,77(1):199-206
The amino acid composition of beef liver d-glycerate dehydrogenase (EC 1.1.1.29) was determined. Results of sodium dodecyl sulfate gel electrophoresis and measurements of the number of NADH bound by the enzyme and the number of the essential sulfhydryl groups suggested that the enzyme was composed of two identical subunits with the molecular weight of 36,000. Close relation between the essential sulfhydryl groups and the coenzyme binding site was also suggested. Effect of an alkylating agent (bromopyruvate) with the structure similar to the substrate was studied. Effects of iodoacetate and iodoacetamide were also studied. It was suggested that these reagents behaved as active-site-directed irreversible inhibitors of the enzyme. Bromopyruvate exhibited a high affinity to the enzyme. Iodoacetate (anionic reagent) had a higher affinity than iodoacetamide (neutral reagent). 相似文献
92.
Etsuro Sugimoto Masaaki Yoshikawa Yutaka Nishida Hideo Chiba 《Bioscience, biotechnology, and biochemistry》2013,77(12):2497-2504
It was indicated from fluorescence spectra and fluorescence titration that a hydrophobic probe, 1-anilino-8-naphthalenesulfonate (ANS), binds to casein components (αs-, β- and κ-caseins). Fluorescence intensity and affinity of ANS-κ-casein complex were larger than that of ANS-αs- and ANS-β-casein complexes. Enhancements of fluorescence intensity of complexes of casein components were observed by the addition of KCI or CaCl2. Reason for the enhancement was postulated to be the increase of the quantum yield of the ANS fluorescence caused by the environmental change of ANS binding region of the casein components.Marked increase of sedimentation coefficient of β-casein in the presence of KCl or CaCl2 at 10°C was caused by the addition of ANS. This may be responsible for the stimulation of the Ca-dependent precipitation of β-casein by the addition of ANS.It was found that αs · κ-association was prevented by ANS and that hydrophobic interaction have an important role for αs · κ-association. 相似文献
93.
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
94.
Background
To induce potent epitope-specific T cell immunity by a peptide-based vaccine, epitope peptides must be delivered efficiently to antigen-presenting cells (APCs) in vivo. Therefore, selecting an appropriate peptide carrier is crucial for the development of an effective peptide vaccine. In this study, we explored new peptide carriers which show enhancement in cytotoxic T lymphocyte (CTL) induction capability.Methodology/Principal Findings
Data from an epitope-specific in vivo CTL assay revealed that phosphatidylserine (PS) has a potent adjuvant effect among candidate materials tested. Further analyses showed that PS-conjugated antigens were preferentially and efficiently captured by professional APCs, in particular, by CD11c+CD11b+MHCII+ conventional dendritic cells (cDCs) compared to multilamellar liposome-conjugates or unconjugated antigens. In addition, PS demonstrated the stimulatory capacity of peptide-specific helper T cells in vivo.Conclusions/Significance
This work indicates that PS is the easily preparable efficient carrier with a simple structure that delivers antigen to professional APCs effectively and induce both helper and cytotoxic T cell responses in vivo. Therefore, PS is a promising novel adjuvant for T cell-inducing peptide vaccines. 相似文献95.
Masahiro Nakajima Ryuta Yoshida Akimasa Miyanaga Koichi Abe Yuta Takahashi Naohisa Sugimoto Hiroyuki Toyoizumi Hiroyuki Nakai Motomitsu Kitaoka Hayao Taguchi 《PloS one》2016,11(2)
Despite the presence of β-1,2-glucan in nature, few β-1,2-glucan degrading enzymes have been reported to date. Recently, the Lin1839 protein from Listeria innocua was identified as a 1,2-β-oligoglucan phosphorylase. Since the adjacent lin1840 gene in the gene cluster encodes a putative glycoside hydrolase family 3 β-glucosidase, we hypothesized that Lin1840 is also involved in β-1,2-glucan dissimilation. Here we report the functional and structural analysis of Lin1840. A recombinant Lin1840 protein (Lin1840r) showed the highest hydrolytic activity toward sophorose (Glc-β-1,2-Glc) among β-1,2-glucooligosaccharides, suggesting that Lin1840 is a β-glucosidase involved in sophorose degradation. The enzyme also rapidly hydrolyzed laminaribiose (β-1,3), but not cellobiose (β-1,4) or gentiobiose (β-1,6) among β-linked gluco-disaccharides. We determined the crystal structures of Lin1840r in complexes with sophorose and laminaribiose as productive binding forms. In these structures, Arg572 forms many hydrogen bonds with sophorose and laminaribiose at subsite +1, which seems to be a key factor for substrate selectivity. The opposite side of subsite +1 from Arg572 is connected to a large empty space appearing to be subsite +2 for the binding of sophorotriose (Glc-β-1,2-Glc-β-1,2-Glc) in spite of the higher Km value for sophorotriose than that for sophorose. The conformations of sophorose and laminaribiose are almost the same on the Arg572 side but differ on the subsite +2 side that provides no interaction with a substrate. Therefore, Lin1840r is unable to distinguish between sophorose and laminaribiose as substrates. These results provide the first mechanistic insights into β-1,2-glucooligosaccharide recognition by β-glucosidase. 相似文献
96.
Since the 1950s, the number of doctorate recipients has risen dramatically in the United States. In this paper, we investigate whether the longevity of doctorate recipients’ publication careers has changed. This is achieved by matching 1951–2010 doctorate recipients with rare names in astrophysics, chemistry, economics, genetics and psychology in the dissertation database ProQuest to their publications in the publication database Web of Science. Our study shows that pre-PhD publication careers have changed: the median year of first publication has shifted from after the PhD to several years before PhD in most of the studied fields. In contrast, post-PhD publication career spans have not changed much in most fields. The share of doctorate recipients who have published for more than twenty years has remained stable over time; the shares of doctorate recipients publishing for shorter periods also remained almost unchanged. Thus, though there have been changes in pre-PhD publication careers, post-PhD career spans remained quite stable. 相似文献
97.
Keisuke Sugimoto Shuhei Tsuchiya Masahiro Omori Ryo Matsuda Masahito Fujio Kensuke Kuroda Masazumi Okido Hideharu Hibi 《Biochemistry and Biophysics Reports》2016
Osseointegration is the structural and functional connection between bone tissues and implants such as titanium dioxide (TiO2). The bone-TiO2 interface is thought to contain proteoglycans. However, exhaustive analysis of the proteins in this layer has not been performed. In this study, we evaluated the bone protein adhered on the surface of TiO2 comprehensively. Pig bone protein was extracted by sequential elutions with guanidine, 0.1 M EDTA, and again with guanidine. The proteins obtained from these extractions were allowed to adhere to an HPLC column packed with TiO2 and were eluted with 0.2 M NaOH. The eluted proteins were identified by LC/MS/MS and included not only proteoglycans but also other proteins such as extracellular matrix proteins, enzymes, and growth factors. Calcium depositions were observed on TiO2 particles incubated with bone proteins, guanidine-extracted proteins adhered to TiO2 displayed significantly high amounts of calcium depositions. 相似文献
98.
99.
The plant‐specific CDKB1‐CYCB1 complex mediates homologous recombination repair in Arabidopsis
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100.
Mouse knockout of guanylyl cyclase C: Recognition memory deficits in the absence of activity changes
Elizabeth A. Mann Chiho Sugimoto Michael T. Williams Charles V. Vorhees 《Genes, Brain & Behavior》2019,18(5)
Guanylyl cyclase C (GC‐C) is found in brain regions where dopamine is expressed. We characterized a mouse in which GC‐C was knocked out (KO) that was reported to be a model of attention deficit hyperactivity disorder (ADHD). We re‐examined this model and controlled for litter effects, used 16 to 23 mice per genotype per sex and assessed an array of behavioral and neurochemical outcomes. GC‐C KO mice showed no phenotypic differences from wild‐type mice on most behavioral tests, or on striatal or hippocampal monoamines, and notably no evidence of an ADHD‐like phenotype. KO mice were impaired on novel object recognition, had decreased tactile startle but not acoustic startle, and females had increased latency on cued training trials in the Morris water maze, but not hidden platform spatial learning trials. Open‐field activity showed small differences in females but not males. The data indicate that the GC‐C KO mouse with proper controls and sample sizes has a moderate cognitive and startle phenotype but has no ADHD‐like phenotype. 相似文献