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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
84.
Yasuhiro Yamada Hirobumi Motoi Shinichi Kinoshita Nobuo Takada Hirosuke Okada 《Applied microbiology》1975,29(3):400-404
An organism isolated from soil and identified as Arthrobacter sp. was studied for its squalene degradation. The degradation product from squalene, which accumulated in the culture broth, was isolated and identified as trans-geranylacetone by mass spectrometry, gas chromatography, infrared spectrometry, and nuclear magnetic resonance spectrometry. Addition of a high concentration of K2HPO4 to the culture medium resulted in accumulation of fairly large amounts of carboxylic acids in addition to geranylacetone. These carboxylic acids were identified as isovaleric, β,β′-dimethylacrylic, geranic, and (+)-(R)-citronellic acids. Among these acids, α,β-saturated carboxylic acids were found to be predominant in quantity. 相似文献
85.
Attempts were made to isolate and identify the unit chemical structure essential for manifestation of the immunoadjuvant activities characteristic of bacterial cell walls. The N-acetylmuramyl-peptide subunit monomers, Nalpha-(N-acetylmuramyl-L-alanyl-D-isoglutaminyl)-Nepsilon-(glycylglycyl)-L-lysyl-D-alanine from the cell walls of Staphylococcus aureus (FDA 209P) and N-acetylmuramyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelic acid and/or N-acetylmuramyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelyl-D-alanine from those of Lactobacillus plantarum (ATCC 8014), were shown to be unit chemical entities with definite adjuvant activity both in stimulation of antibody production and in induction of delayed-type hypersensitivity to ovalbumin when administered to guinea-pigs as water-in-oil emulsions. 相似文献
86.
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
87.
Kenji Yamamoto Hiroshi Yoshikura Noriko Takahashi Ichizo Kobayashi 《Molecular & general genetics : MGG》1988,212(3):393-404
Summary Gene conversion, the non-reciprocal transfer of sequence information between homologous DNA sequences, has been reported in lower eukaryotes, mammals and in Escherichia coli. In an E. coli rec
+ strain, we established a plasmid carrying two different deleted neo genes (neoDL and neoDR) in an inverted orientation and then selected for homologous recombination events that had reconstructed an intact neo
+ gene. We found some plasmids that had apparently experienced intramolecular gene conversion. Further evidence, however, suggests that they are products of multiple rounds of reciprocal crossing-over,apparently involving two plasmid molecules. First, most of the Neo+ clones contained multiple types of Neo+ plasmids, although the frequency of producing the neo
+ clones was low. Second, all the neo
+ clones also contained, as a minority, one particular form of dimer, which can be formed by reciprocal crossing-over between neoDL of one plasmid molecule and neoDR of another plasmid molecule. Third, in reconstruction experiments, we cloned and purified this dimer and transferred it back into the rec
+ cells. The dimer gave rise to clones containing multiple types of neo
+ recombinant monomers, including those apparent gene conversion types, and containing only few molecules of this dimer plasmid. 相似文献
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Takimoto Yuki Monkawa Akira Nagata Kohki Kobayashi Masahiro Kinoshita Mariko Gessei Tomoko Mori Toshiya Kagi Hiroyuki 《Plasmonics (Norwell, Mass.)》2020,15(3):805-811
Plasmonics - Detection and monitoring of SO2 is important because it is a representative toxic gas in the atmospheric environment that is emitted from industrial and natural processes. Localized... 相似文献
90.
Tsuchiya Kenji Tomioka Noriko Sano Tomoharu Kohzu Ayato Komatsu Kazuhiro Imai Akio Hayakawa Kazuhide Nagata Takamaru Okamoto Takahiro Hirose Yoshinori 《Limnology》2020,21(1):87-96
Limnology - In Lake Biwa, the largest lake in Japan, external pollutant loads have decreased since the 1980s, leading to improved water quality, such as reduction in biochemical oxygen demand (BOD)... 相似文献