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91.
Electrolyzed strong acid water (ESW) containing free chlorine at various concentrations is becoming to be available in clinical settings as a disinfectant. ESW is prepared by electrolysis of a NaCl solution, and has a corrosive activity against medical instruments. Although lower concentrations of NaCl and free chlorine are desired to eliminate corrosion, the germicidal effect of ESW with low NaCl and free-chlorine concentrations (ESW-L) has not been fully clarified. In this study, we demonstrated that ESW-L possesses bactericidal activity against Mycobacteria and spores of Bacillus subtilis. The effect was slightly weaker than that of ESW containing higher NaCl and free-chlorine concentrations (ESW-H), but acceptable as a disinfectant. To clarify the mechanism of the bactericidal activity, we investigated ESW-L-treated Pseudomonas aeruginosa by transmission electron microscopy, a bacterial enzyme assay and restriction fragment length polymorphism pattern (RFLP) assay. Since the bacterium, whose growth was completely inhibited by ESW-L, revealed the inactivation of cytoplasmic enzyme, blebs and breaks in its outer membrane and remained complete RFLP of DNA, damage of the outer membrane and inactivation of cytoplasmic enzyme are the important determinants of the bactericidal activity.  相似文献   
92.
4-Dimethylaminoazobenzene-2-carboxylic acid (DMBC) was utilized as a necessary carbon and nitrogen source by Pseudomonas stutzeri IAM 12097. o-Aminobenzoic acid (o-ABA), N,N-dimethyl-p-phenylenediamine (DMPA) and cathecol were identified as intermediates of DMBC degradation. DMBC was degraded at a concentration below 70 mol dm–3. The ability to utilize DMBC in P. stutzeri was lost spontaneously to some extent. When P. stutzeri was cured of plasmid DNA (approximately 8 MDal) by treatment with mitomycin C, acridine orange, and chloramphenicol, DMBC was not utilized by the resultant strain. These facts suggest that the degradative ability on DMBC in P. stutzeri is controlled by plasmid DNA. Correspondence to: C. Yatome  相似文献   
93.
Crystal Violet (BV3), a typical triphenylmethane dye, was degraded by growing cells of Nocardia corallina IAM 12121, although their growth was inhibited at the initial stage of incubation. The dye was degraded at a low concentration, below 5 mol dm–3. The growth of the cells was completely inhibited at a dye concentration of 7 mol dm–3. A degradation product of BV3 was identified as 4,4-bis(dimethylamino) benzophenone (Michler's ketone; MK) by gas chromatography-mass spectrometry. The product was obtained in a reasonable yield since it was not further metabolized by N. corallina IAM 12121. Correspondence to: C. Yatome  相似文献   
94.
Differential centrifugation of the subcellular particles oftomato fruit was carried out after brief homogenization of thetomato fruit with a blendor in 0.5 M sucrose, containing 0.2M Tris-HCl buffer, pH 8.0. About 60% of the catalase activitywas detected in the peroxisomal fraction. However, most of theacid phosphatase and carboxypeptidase, which are marker enzymesfor lysosomes, were detected in the soluble fraction, as wasglucose-6-phosphate dehydrogenase, a marker enzyme for solublecytosol. Similar results were obtained from differential centrifugationof the tomato leaf homogenate. This absence of the lysosomalparticles in the tomato fruit and leaves is discussed, particularlyas an indication of the presence of hydrolytic enzymes in thecentral vacuoles of mature plant cells. (Received February 3, 1975; )  相似文献   
95.
R factors fi(+) and fi(-), with various combinations of drug-resistance markers and isolated from independent sources, were transduced by phage P1kc in Escherichia coli and by phage P22 in Salmonella typhimurium. Usually the entire R factor was transduced by P1kc in E. coli, as indicated by the absence of segregation of the drug-resistance markers from their conjugal transferability. In contrast, the patterns of segregation of the drug-resistance markers and their conjugal transferability differed considerably among various R factors after transduction by P22 in S. typhimurium. Transduction frequencies varied among R factors in both transduction systems.  相似文献   
96.
To clarify the process of avian sex chromosome differentiation in palaeognathous birds, we performed molecular and cytogenetic characterization of W chromosome-specific repetitive DNA sequences for elegant crested tinamou (Eudromia elegans, Tinamiformes) and constructed comparative cytogenetic maps of the Z and W chromosomes with nine chicken Z-linked gene homologues for E. elegans and ostrich (Struthio camelus, Struthioniformes). A novel family of W-specific repetitive sequences isolated from E. elegans was found to be composed of guanine- and cytosine-rich 293-bp elements that were tandemly arrayed in the genome as satellite DNA. No nucleotide sequence homologies were found for the Struthioniformes and neognathous birds. The comparative cytogenetic maps of the Z and W chromosomes of E. elegans and S. camelus revealed that there are partial deletions in the proximal regions of the W chromosomes in the two species, and the W chromosome is more differentiated in E. elegans than in S. camelus. These results suggest that a deletion firstly occurred in the proximal region close to the centromere of the acrocentric proto-W chromosome and advanced toward the distal region. In E. elegans, the W-specific repeated sequence elements were amplified site-specifically after deletion of a large part of the W chromosome occurred.  相似文献   
97.
98.
Anthocyanin synthesis in the broom sorghum, Sorghum bicolor Moench cvs. Acme Broomcorn and Sekishokuzairai-Fukuyama, is mediated separately or synergistically by an ultraviolet light-B (UV-B) photoreceptor and phytochrome. When seedlings were exposed to moderate low temperatures ranging from 12 to 20° C before irradiation, only the phytochrome-mediated anthocyanin synthesis was markedly enhanced compared with the control, which was kept throughout at 24° C; synthesis mediated by the UV-B photoreceptor was unaffected. The effectiveness of an exposure to 20° C increased as the duration of exposure increased up to 24 h and as the time of exposure became closer to the time of irradiation. However, when seedlings were exposed to 20° C from after irradiation until harvest, anthocyanin syntheses induced by both UV-B and red light were equally suppressed, probably due to the general reduction of metabolism involved in anthocyanin synthesis that is a consequence of lower temperature. The results support the view that the signal transduction of the pyhtochrome system is different from that of the UV-B photoreceptor, and indicate that the phytochrome system may involve a step or steps which are amplified by a previous exposure to the moderate low temperature.Abbreviations FR far-red light - LT low temperature - MLT moderate low temperature - Pfr far-red-light-absorbing form of phytochrome - R red light - UV ultraviolet light - UV-B ultraviolet light-B We thank Drs. Y. Takeuchi (Shionogi Pharmaceutical Company, Aburahi, Shiga) and K. Hosaka (the Experimental Farm, Kobe University, Kasai) for seeds; Dr. M. Watanabe and Mr. M. Kubota (the National Institute for Basic Biology, Okazaki) for operation of the spectrograph. This work was supported by grants from the Yamada Science Foundation, Ministry of Education (No. 63480015 and 03454048), and the National Institute for Basic Biology (Large Spectrograph grant No. 91-523).  相似文献   
99.
Mitochondrial DNA D-loop sequences (472 bases) for endangered Japanese golden eagles (Aquila chrysaetos japonica) were investigated to evaluate-intrapopulational genetic variations. Among 23 golden eagles, including origin-known eagles caught in the wild and origin-unknown eagles, 10 variable sites were found in the 472 base-sequences. From the nucleotide substitutions, five haplotypes of D-loop sequences were identified, indicating the occurrence of at least three maternal lineages in golden eagles around Japan. Distribution patterns of D-loop haplotypes suggested a wide genetic communication between local populations around Japan prior to a recent habitat fragmentation and a decrease in the population size. In addition, cytogenetic analysis showed that a karyotype specific to the Japanese golden eagle is consistently 2n=62 including eight microchromosomes. Based on mitochondrial DNA and karyotype data, it is likely that golden eagle populations from Japan and the Korean Peninsula together form a common conservation unit. These results provide an important framework for conservation actions for Japanese golden eagle populations in zoos, and in situ reintroduction and translocation programs. Zoo Biol 17:111–121, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
100.
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