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211.
The NSm nonstructural protein of Rift Valley fever virus (family Bunyaviridae, genus Phlebovirus) has an antiapoptotic function and affects viral pathogenesis. We found that NSm integrates into the mitochondrial outer membrane and that the protein''s N terminus is exposed to the cytoplasm. The C-terminal region of NSm, which contains a basic amino acid cluster and a putative transmembrane domain, targeted the protein to the mitochondrial outer membrane and exerted antiapoptotic function. 相似文献
212.
A theory of the double layer interaction regulated by the Donnan potential between two ion-penetrable membranes in an electrolyte solution developed previously by Ohshima and Kondo is extended to the case in which the membranes consist of many layers having different thickness and densities of membrane-fixed charges. The interaction force is found to be determined mainly by the contributions from layers located within the depth of 1/kappa (kappa, Debye-Hückel parameter) from the membrane surface. It is also predicted that the interaction force may alter its sign with changing electrolyte concentration. 相似文献
213.
214.
Establishing different types of conservation zones is becoming commonplace. However, spatial prioritization methods that can accommodate multiple zones are poorly understood in theory and application. It is typically assumed that management regulations across zones have differential levels of effectiveness (“zone effectiveness”) for biodiversity protection, but the influence of zone effectiveness on achieving conservation targets has not yet been explored. Here, we consider the zone effectiveness of three zones: permanent closure, partial protection, and open, for planning for the protection of five different marine habitats in the Vatu-i-Ra Seascape, Fiji. We explore the impact of differential zone effectiveness on the location and costs of conservation priorities. We assume that permanent closure zones are fully effective at protecting all habitats, open zones do not contribute towards the conservation targets and partial protection zones lie between these two extremes. We use four different estimates for zone effectiveness and three different estimates for zone cost of the partial protection zone. To enhance the practical utility of the approach, we also explore how much of each traditional fishing ground can remain open for fishing while still achieving conservation targets. Our results show that all of the high priority areas for permanent closure zones would not be a high priority when the zone effectiveness of the partial protection zone is equal to that of permanent closure zones. When differential zone effectiveness and costs are considered, the resulting marine protected area network consequently increases in size, with more area allocated to permanent closure zones to meet conservation targets. By distributing the loss of fishing opportunity equitably among local communities, we find that 84–88% of each traditional fishing ground can be left open while still meeting conservation targets. Finally, we summarize the steps for developing marine zoning that accounts for zone effectiveness. 相似文献
215.
216.
Nobuya Katagiri Hideaki Kokufuda Masashi Makino Robert Vince Chikara Kaneko 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):81-89
Abstract The deamination of cyclaradine corresponding to a carbocyclic analogue of ara-A having anti-HSV activity by adenosine deaminase was examined under various pressure. The deamination of (+)- and (±)-cyclaradine was remarkably facilitated by high pressure, and the rate was increased with increasing of pressure. However, (-)-cyclaradine was not deaminated even under high pressure. 相似文献
217.
DNA polymerase preferentially inserts purine nucleotides opposite non-instructive lesions such as abasic sites during DNA replication. In order to elucidate the mechanism of the preferential insertion, a DNA template containing a model abasic site and primers containing 4 different nucleotides (A,G,C,T) at primer terminus were synthesized. The stability of the primer terminus nucleotide placed opposite the abasic site was evaluated on the basis of its sensitivity to 3'-5' exonuclease associated with DNA polymerase. 相似文献
218.
Hyperproduction of phosphate-binding protein, phoS, and pre-phoS proteins in Escherichia coli carrying a cloned phoS gene 总被引:11,自引:0,他引:11
T Morita M Amemura K Makino H Shinagawa K Magota N Otsuji A Nakata 《European journal of biochemistry》1983,130(3):427-435
A large amount of phosphate-binding protein, the phoS gene product, accumulated in the periplasmic space of the cells when an Escherichia coli strain carrying a multicopy plasmid containing a chromosomal fragment of the phoS-phoT region (pSN507) was grown in a low-phosphate medium. When the same strain carrying a plasmid containing only the phoS gene (pSN518 or pSN5182) was grown in low-phosphate medium, phosphate-binding protein accumulated in the periplasm, and in addition a larger protein accumulated in the non-periplasmic fraction. The apparent Mr of this protein and the phosphate-binding protein were 39000 and 35000 respectively, as judged by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. This larger protein showed immunological cross-reaction with the phosphate-binding protein. The 39000-Mr protein was also detected in cells carrying pSN507 when the proteins were pulse-labeled with radioactive amino acids. From these findings, together with the fact that this protein is recovered from the membrane fraction, we conclude that this protein is an unsecreted precursor protein of the phosphate-binding protein. Kinetics and regulation of accumulation of these proteins were studied. This system will be useful for preparation and purification of the precursor protein for biochemical studies in relation to the mechanism of protein secretion. 相似文献
219.
Yuki Kanase Takafumi Kitada Hidetsugu Tabata Kosho Makino Tetsuta Oshitari Hiromi Ohashi Takashi Yoshinaga Hideaki Natsugari Hideyo Takahashi 《Bioorganic & medicinal chemistry》2018,26(9):2508-2513
The physicochemical properties of 4-substituted carbamazepine derivatives were investigated. It was elucidated that the 4-substitution is not effective in reducing the rotations (E/Z) about the N—C1′ axes around the outer carbamoyl moiety. However, the atropisomers were isolated with high stereochemical stability, meaning that the 4-substitution reduced the butterfly motion of the tricyclic ring system efficiently. The Cl/CH3-substituted carbamazepine derivatives showed greater inhibitory effects on hNav1.2 channel currents compared with carbamazepine, although no difference in the activity between enantiomers was observed. 相似文献
220.
Akira Makino Anna Miyazaki Ayaka Tomoike Hiroyuki Kimura Kenji Arimitsu Masahiko Hirata Yoshiro Ohmomo Ryuichi Nishii Hidehiko Okazawa Yasushi Kiyono Masahiro Ono Hideo Saji 《Bioorganic & medicinal chemistry》2018,26(8):1609-1613
Tyrosine kinase inhibitors for epidermal growth factor receptor (EGFR-TKIs) are used as molecular targeted therapy for non-small cell lung cancer (NSCLC) patients. The therapy is applied to the patients having EGFR-primary L858R mutation, but drug tolerance caused by EGFR-secondary mutation is occurred within one and half years. For the non-invasive detection of the EGFR-TKIs treatment positive patients by positron emission tomograpy (PET) imagaing, fluorine-18 labeled thienopyrimidine derivative, [18F]FTP2 was newly synthesized. EGFR inhibition assay, cell uptake study, and blocking study indicated [18F]FTP2 binds with high and selective affinity for EGFR with L858R mutation, and not with L858R/T790M dual mutations. On animal PET study using tumor bearing mice, H3255 cells expressing L858R mutated EGFR was more clearly visualized than H1975 cells expressing L858R/T790M dual mutated EGFR. [18F]FTP2 has potential for detecting NSCLC which is susceptible to EGFR-TKI treatment. 相似文献