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101.
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Poly(L -lysine) having dansyl (5-dimethylamino-1-naphthalene-sulfonyl) groups to its side chains was prepared. The fluorescence spectra and fluorescence anisotropy ratios of the dansyl (DNS) group were measured in various conditions. In aqueous solution the increase in emission intensity was observed reflecting the alkali-induced coil-to-helix transition. In aqueous-methanolic solutions with methanol content above 60 wt %, the poly(L -lysine) with DNS group (DNS-PLL) was probed to show α-helical conformation from CD spectra. With addition of alkali, the increase in fluorescence intensity of α-helical DNS-PLL and the drastic change in fluorescence anisotropy ratio were observed. In this case the rotational mobility of DNS probe decreases, gives a minimum at a certain concentration of added alkali, and then increases again up to approximately the initial level. At the concentration where the rotational mobility gives the minimum, intensity of scattered light gives a maximum. This shows that suppression of the mobility of DNS side chains is caused by the intermolecular aggregation of α-helical DNS-PLL. This concentration of added alkali corresponds to the midpoint of neutralization to charged side chains of the DNS-PLL. The interaction that causes aggregate of α-helical DNS-PLL is suggested to be the intermolecular hydrogen bonding between neutralized and unneutralized side chains. © 1994 John Wiley & Sons, Inc. 相似文献
103.
In the livers of fasted rats, the activity of peroxisomal palmitocyl-CoA oxidation (NADH production) was increased more rapidly and markedly than that of mitochondrial carnitine palmitoyltransferase, which is the rate limiting enzyme of mitochondrial beta-oxidation. The peroxisomal oxidizing activity was about twice that of the control throughout the period of fasting (1-7 days). carnitine acetyltransferase activity was increased to a similar extent in both peroxisomes and mitochondria. A possible physiological role of liver peroxisomes may thus be as an effective supply of NADH2, acetyl residues and short and medium-length fatty acyl-CoA in the cells on the enhancement of peroxisomal beta-oxidation of the animals under starvation; these substances thus produced may be transported into the mitochondria as energy sources. 相似文献
104.
Kan Fujino Masayuki Horie Tomoyuki Honda Shoko Nakamura Yusuke Matsumoto Ivo M. B. Francischetti Keizo Tomonaga 《PloS one》2012,7(12)
Bornavirus, a non-segmented, negative-strand RNA viruses, is currently classified into several genetically distinct genotypes, such as Borna disease virus (BDV) and avian bornaviruses (ABVs). Recent studies revealed that bornavirus genotypes show unique sequence variability in the putative 5′ untranslated region (5′ UTR) of X/P mRNA, a bicistronic mRNA for the X protein and phosphoprotein (P). In this study, to understand the evolutionary relationship among the bornavirus genotypes, we investigated the functional interaction between the X and P proteins of four bornavirus genotypes, BDV, ABV genotype 4 and 5 and reptile bornavirus (RBV), the putative 5′ UTRs of which exhibit variation in the length. Immunofluorescence and immunoprecipitation analyses using mammalian and avian cell lines revealed that the X proteins of bornaviruses conserve the ability to facilitate the export of P from the nucleus to the cytoplasm via interaction with P. Furthermore, we showed that inter-genotypic interactions may occur between X and P among the genotypes, except for X of RBV. In addition, a BDV minireplicon assay demonstrated that the X and P proteins of ABVs, but not RBV, can affect the polymerase activity of BDV. This study demonstrates that bornaviruses may have conserved the fundamental function of a regulatory protein during their evolution, whereas RBV has evolved distinctly from the other bornavirus genotypes. 相似文献
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Takashi Misawa Genichiro Tsuji Takeo Takahashi Eiji Ochiai Ken-ichiro Takagi Kyohei Horie Shinji Kakuda Midori Takimoto-Kamimura Masaaki Kurihara Yosuke Demizu 《Bioorganic & medicinal chemistry》2018,26(23-24):6146-6152
Non-secosteroidal VDR ligands without any assymmetric carbon were designed and synthesized based on the structure of the previously reported non-secosteroidal VDR agonist LG190178. The VDR-agonistic activity of all synthesized compounds was evaluated, and 7b emerged as a potent agonist activity with an EC50 value of 9.26?nM. Moreover, a docking simulation analysis was also performed to determine the binding mode of 7b with VDR-LBD. 相似文献
107.
Yasuhito Sakuraba Akihiro Yamasato Ryouichi Tanaka Ayumi Tanaka 《Plant Physiology and Biochemistry》2007,45(10-11):740-749
Higher plants acclimate to various light environments by changing the antenna size of a light-harvesting photosystem. The antenna size of a photosystem is partly determined by the amount of chlorophyll b in the light-harvesting complexes. Chlorophyllide a oxygenase (CAO) converts chlorophyll a to chlorophyll b in a two-step oxygenation reaction. In our previous study, we demonstrated that the cellular level of the CAO protein controls accumulation of chlorophyll b. We found that the amino acids sequences of CAO in higher plants consist of three domains (A, B, and C domains). The C domain exhibits a catalytic function, and we demonstrated that the combination of the A and B domains regulates the cellular level of CAO. However, the individual function of each of A and B domain has not been determined yet. Therefore, in the present study we constructed a series of deleted CAO sequences that were fused with green fluorescent protein and overexpressed in a chlorophyll b-less mutant of Arabidopsis thaliana, ch1-1, to further dissect functions of A and B domains. Subsequent comparative analyses of the transgenic plants overexpressing B domain containing proteins and those lacking the B domain determined that there was no significant difference in CAO protein levels. These results indicate that the B domain is not involved in the regulation of the CAO protein levels. Taken together, we concluded that the A domain alone is involved in the regulatory mechanism of the CAO protein levels. 相似文献
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Separation of novel phosphoproteins of Porphyromonas gingivalis using phosphate‐affinity chromatography 下载免费PDF全文
Masashi Izumigawa Yoshiaki Hasegawa Ryota Ikai Toshi Horie Megumi Inomata Takeshi Into Noriyuki Kitai Fuminobu Yoshimura Yukitaka Murakami 《Microbiology and immunology》2016,60(10):702-707
Phosphorylation of serine, threonine and tyrosine is a central mechanism for regulating the structure and function of proteins in both eukaryotes and prokaryotes. However, the action of phosphorylated proteins present in Porphyromonas gingivalis, a major periodontopathogen, is not fully understood. Here, six novel phosphoproteins that possess metabolic activities were identified, namely PGN_0004, PGN_0375, PGN_0500, PGN_0724, PGN_0733 and PGN_0880, having been separated by phosphate‐affinity chromatography. The identified proteins were detectable by immunoblotting specific to phosphorylated Ser (P‐Ser), P‐Thr, and/or P‐Tyr. These results imply that novel phosphorylated proteins might play an important role for regulation of metabolism in P. gingivalis. 相似文献