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81.
Saccharomycodes ludwigii, supposed to be petite-negative, gave rise to respiration-deficient mutants when acriflavine and ultraviolet irradiation, respectively, were applied to this yeast, strain IFO 1194. The frequency of such mutants was very low as compared with that in Saccharomyces cerevisiae and other petite-positive yeasts. Cytochrome composition was characterized by spectrophotometry at the temperature of liquid nitrogen. The respiratory mutants examined contained cytochrome c unaltered in quality and quantity. Cytochrome b was often present only in small amounts though never absent, while cytochrome a+a3 was either present or absent. The respiratory mutants could form zygotes after conjugation with a wild-type culture of opposite mating type ( vs. a). The hybridization and segregation analysis of spore tetrads showed the inheritance of respiratory mutant character to be either Mendelian or non-Mendelian and similar to that of pet (nuclear) and rho- (cytoplasmic) mutants, respectively, in Saccharomyces cerevisiae. 相似文献
82.
Histone, protamine, poly-L-arginine, and poly-L-lysine enhance the binding of adenosine 3′,5′-monophosphate (cyclic AMP) to rat liver cyclic AMP-dependent protein kinase as determined by Millipore filtration assay. Poly-L-glutamic acid and poly-L-aspartic acid suppress cyclic AMP-binding stimulated by histone. Poly-L-glutamic acid and poly-L-aspartic acid are effective against protein kinase and result in decrease in initial reaction velocity when histone is used as a protein substrate. Incubation of cyclic AMP-dependent protein kinase with 6 μg poly-L-glutamic acid produces half-maximal inhibition of cyclic AMP-dependent protein kinase when 30 μg histone is used as substrate. 相似文献
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84.
Tetsuya Kawai Iwase Kazuhiko Noriko Takaya Yuko Yamaguchi Ryuta Kishii Yasushi Kohno Haruaki Kurasaki 《Bioorganic & medicinal chemistry letters》2017,27(4):1045-1049
We attempted to optimize sulfonamide-based non-alkyne LpxC inhibitors by focusing on improvements in enzyme inhibitory and antibacterial activity. It was discovered that inhibitors possessing 2-aryl benzofuran as a hydrophobe exhibited good activity. In particular, compound 21 displayed impressive antibacterial activity (E. coli MIC = 0.063 μg/mL, K. pneumoniae MIC = 0.5 μg/mL, and P. aeruginosa MIC = 0.5 μg/mL), and is a promising lead for further exploration as an antibacterial agent. 相似文献
85.
Kinji Endo Yōko Umeyama Junko Nakajima Hiroyasu Kawai 《Bioscience, biotechnology, and biochemistry》2013,77(7):1545-1551
Three kinds of nuclease preparations, each of which having both endonuclease activity that formed 5′-mononucleotides and 3′-nucleotidase activity, were separated and partially purified from Shii-take, Lentinus edodes. Both enzyme activities of each preparation showed a similar thermostability and electrophoretic mobility on Polyacrylamide gel, and a competitive relationship was observed between RNA and 3′-AMP in their enzyme reactions. From these results, it is concluded that both enzyme activities of these three preparations reside in a single protein, respectively. They resemble one another in substrate specificity, cleavage pattern of RNA and thermostability, but are distinguishable from one another by molecular weight, electrophoretic mobility and optimum pH for degradation of RNA. 相似文献
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Ohara Chisato Sekiguchi Atsushi Takakura Shu Endo Yuka Tamura Naho Kikuchi Hiroe Maruo Kazushi Sugawara Norio Hatano Kenji Kawanishi Hitomi Funaba Misako Sugawara Ayako Nohara Nobuhiro Kawai Keisuke Fukudo Shin Sudo Nobuyuki Cooper Zafra Yoshiuchi Kazuhiro Ando Tetsuya 《BioPsychoSocial medicine》2020,14(1):1-3
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017. 相似文献
88.
Hashem Shaharior Kawai Koichiro Fatsi Patrick Senam Kofi Kodama Atsuya Saito Hidetoshi 《Limnology》2020,21(1):151-163
Limnology - The purpose of this study was to estimate the genetic distance, diversity and relationship of two large groups of Malawian cichlid, ‘mbuna’ living in rocky area and feeding... 相似文献
89.
Taxonomy of the little‐studied brown algal species Punctaria mageshimensis (Ectocarpales s.l.) was reexamined by molecular phylogeny and morphology. In the genetic analyses of newly collected specimens using plastid rbcL and psaA gene sequences, the specimens morphologically referable to P. mageshimensis were phylogenetically distant from Ectocarpales s.l. and were included in the clade of Spatoglossum (Dictyotales). Morphological reexamination of the type specimen and newly collected specimens confirmed its systematic position in Dictyotales: Branched thallus; cushion‐shaped rhizoidal holdfast occasionally forming secondary holdfast at the bottom of the thallus; many discoidal plastids without pyrenoid per cell; tetrasporangium‐like reproductive structures with dark, homogeneous cell content; occurrence of hair tufts. Genetically P. mageshimensis was most related to a reported sequence of Spatoglossum asperum, but P. mageshimensis was considerably different from S. asperum as well as other known Spatoglossum species in the deep habitat and in having scarcely‐branched lanceolate and considerably thickened thallus. In conclusion, we propose the transfer of P. mageshimensis to Spatoglossum as S. mageshimense comb. nov. 相似文献