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731.
732.
Interaction between new N atom-containing tumor inhibitors (1-9) and nucleic acids has been investigated utilizing the spectroscopic methods efficiently. On the basis of their data, it is well suggested that FNT-4 (4) and benzo[c]phenanthridine alkaloids (6-8) bind to nucleic acids by a fashion involving intercalation of aromatic molecule(s).  相似文献   
733.
734.
735.
Pleurotus salmoneostramineus is a pink mushroom. This pink color is a protein and forms a complex with 3H-indol-3-one. The gene encoding the pink-colored protein from P. salmoneostramineus (PsPCP) was cloned, and its sequence was elucidated as a 681-bp. The ORF encodes 226 amino acid residues. The amino acid sequence of the protein did not show any significant homology in the DDBJ/EMBL/GenBank databases. Recombinant PsPCP was expressed as the soluble form in E. coli. The reaction mixture of purified recombinant PsPCP and 3H-indol-3-one showed a pink color as the native pigment. A real-time PCR analysis revealed the strong expression of PsPCP in the primordium formation stage of the life cycle of the fungus; however, its expression decreased with the maturation of the fruit body. A comparison of PsPCP gene expression profiles between two strains revealed high levels in the dark-colored strain.  相似文献   
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Yeast responds to alterations in plasma membrane lipid asymmetry and external alkalization via the sensor protein Rim21 in the Rim101 pathway. However, the sensing mechanism used by Rim21 remains unclear. Here, we found that the C-terminal cytosolic domain of Rim21 (Rim21C) fused with GFP was associated with the plasma membrane under normal conditions but dissociated upon alterations in lipid asymmetry or external alkalization. This indicates that Rim21C contains a sensor motif. Rim21C contains multiple clusters of charged residues. Among them, three consecutive Glu residues (EEE motif) were essential for Rim21 function and dissociation of Rim21C from the plasma membrane in response to changes in lipid asymmetry. In contrast, positively charged residues adjacent to the EEE motif were required for Rim21C to associate with the membrane. We therefore propose an “antenna hypothesis,” in which Rim21C moves to or from the plasma membrane and functions as the sensing mechanism of Rim21.  相似文献   
738.
A total of 518 fecal samples collected from 183 apparently healthy cattle, 180 pigs and 155 broilers throughout Japan in 1999 were examined to determine the prevalence and antimicrobial susceptibility of Salmonella. The isolation rates were 36.1% in broilers, 2.8% in pigs and 0.5% in cattle. S. enterica Infantis was the most frequent isolate, found in 22.6% of broiler fecal samples. Higher resistance rates were observed against oxytetracycline (82.0%), dihydrostreptomycin (77.9%), kanamycin (41.0%) and trimethoprim (35.2%). Resistance rates to ampicillin, ceftiofur, bicozamycin, chloramphenicol and nalidixic acid were <10%. CTX-M-2 β-lactamase producing S. enterica Senftenberg was found in the isolates obtained from one broiler fecal sample. This is the first report of cephalosporin-resistant Salmonella directly isolated from food animal in Japan.  相似文献   
739.
The red alga Laurencia nipponica comprises various chemical races distributed relative to the ocean current in Japanese coastal areas. We investigated the chemical compositions and chemical races of L. nipponica distributed from the Kunashiri and Etorofu Islands, the confluence of the Soya warm current and Oya-shio cold current. Two new halogenated secondary metabolites, deacetylneonipponallene ( 1 ) and neopacifenol ( 2 ), along with four known compounds, deoxyprepacifenol ( 3 ), pacifenol ( 4 ), halo-chamigrene diether ( 5 ), and isolaurallene ( 6 ) were isolated from L. nipponica collected at Chikappunai, Kunashiri Island, while Zaimokuiwa (Kunashiri Island) and Sana (Etorofu Island) populations contained 3 , 7-hydroxylaurene ( 7 ), 2,10-dibromo-3-chloro-9-hydroxy-α-chamigrene ( 8 ), and (3Z)-laurefucin ( 9 ). The structures of 1 and 2 were established using spectroscopic methods. The chemical races of L. nipponica distributed in this area were divided into 6 - and 9 -producing races. Interestingly, both races contained 4 as an additional race-index, as well as its derivatives, 2 and 5 . To the best of our knowledge, this is the first example of a race comprising a mixture of two race-index compounds, suggesting that the convergence of two currents causes the production of new and diverse chemical races in this species.  相似文献   
740.
Journal of Plant Research - The article Sucrose affects the developmental transition of rhizomes in Oryza longistaminata, written by Kanako Bessho-Uehara, Jovano Erris Nugroho, Hirono Kondo,...  相似文献   
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