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391.
The basidiomycete Lyophyllum decastes was transformed by means of particle bombardment. We isolated five transformants under twelve conditions differing in the
two parameters of target distance and helium pressure. The transformation frequency was one transformant/μg DNA. In the transformants,
plasmid DNAs were integrated into the genomic DNA and stably maintained. This is the first report on transformation of L. decastes by particle bombardment. 相似文献
392.
Toru Matsui Yasumasa Dekishima Makoto Ueda 《Applied microbiology and biotechnology》2014,98(18):7699-7706
Chiral organic sulfoxides (COSs) are important compounds that act as chiral auxiliaries in numerous asymmetric reactions and as intermediates in chiral drug synthesis. In addition to their optical resolution, stereoselective oxidation of sulfides can be used for COS production. This reaction is facilitated by oxygenases and peroxidases from various microbial resources. To meet the current demand for esomeprazole, a proton pump inhibitor used in the treatment of gastric-acid-related disorders, and the (S)-isomer of an organic sulfoxide compound, omeprazole, a successful biotechnological production method using a Baeyer-Villiger monooxygenase (BVMO), was developed. In this review, we summarize the recent advancements in COS production using biocatalysts, including enzyme identification, protein engineering, and process development. 相似文献
393.
394.
S-isorobinal as the female sex pheromone from an alarm pheromone emitting mite, Rhizoglyphus setosus
Atsuko Mizoguchi Kenjiro Murakami Nobuhiro Shimizu Naoki Mori Ritsuo Nishida Yasumasa Kuwahara 《Experimental & applied acarology》2005,36(1):107-117
The female sex pheromone of Rhizoglyphus setosus Manson (Astigmata: Acaridae) was identified as S-isorobinal (4S-4-isopropenyl-3-oxo-1-cyclohexene-1-carboxyaldehyde), which stimulated males sexually and enhanced the frequency of the male’s tapping and mounting behavior. Although the female hexane extract indicated no sign of sex pheromone activity against tested males, possibly due to the presence of the alarm pheromone neryl formate, an SiO2 column fraction containing isorobinal elicited sex pheromone activity at a dose of one female equivalent. The stereochemistry of natural isorobinal was identified as S by an HPLC using a chiral column. Both S- and R-isorobinals exhibited maximum activity at the same dose of 1 and 10 ng with a convex dose–response relationship. Amounts of S-isorobinal were determined to be 11.7 ± 1.0 ng per female and 6.4 ± 1.3 ng per male by GLC. This is the second example of two pheromones (the alarm pheromone neryl formate, and the sex pheromone S-isorobinal) demonstrated to be components of the same opisthonotal gland secretion. 相似文献
395.
The CO2 absorption rate of the leaves and the CO2 evolutionrate of the roots of Cattleya were determined simultaneouslyduring alternate light and dark periods. The CO2 evolution rateof the roots decreased as the CO2 absorption rate of leavesincreased in the dark period and increased as the absorptionrate of the leaves decreased in the light period. Severing theleaves in the dark increased the CO2 evolution rate in rootsto the value found in the light. (Received April 16, 1984; Accepted September 7, 1984) 相似文献
396.
Tetsuro Ito Ryosuke Hoshino Yasumasa Hara Masayoshi Oyama Munekazu Iinuma 《Phytochemistry letters》2013,6(2):193-197
In this study, we isolated a new glucoside of the resveratrol trimer (hopeaside E) from the stem wood of Hopea utilis. The glucoside structure is partially composed of balanocarpol (resveratrol dimer) after oxidative condensation of the (E)-resveratrol-10-C-β-glucopyranoside. The structure elucidation was achieved by spectroscopic analysis including NMR experiments, and the absolute configuration was determined on the basis of the comparative configurational analysis with the β-d-glucopyranosyl group. Conformational analysis was also performed by considering deshielding effects due to aromatic rings using computational methods of molecular modeling. The aglycone has six asymmetric carbons with two aliphatic hydroxyl groups attached to them that has not been reported in any other resveratrol derivative studies. 相似文献
397.
doi: 10.1111/j.1741‐2358.2012.00664.x Relationship between behavioral and psychological symptoms of dementia and oral health status in the elderly with vascular dementia Objectives: The aim of this study was to clarify the relationship between behavioral and psychological symptoms of dementia (BPSD) and oral status in the elderly with vascular dementia. Background: There have been some reports of a relationship between disease symptoms and oral status in the elderly with Alzheimer’s disease, but few reports have been conducted in the elderly with vascular dementia. Until now, the relationship between BPSD and oral status has been unknown. Materials and methods: An investigation was conducted concerning BPSD and oral status among 57 subjects with vascular dementia (mean age, 85.7 ± 5.5 years). The wearing of dentures and oral activities of daily living (oral ADL) were examined. Results: Subjects with activity disturbances and those with aggressiveness had significantly lower rates of denture wearing than those without these two symptoms (p < 0.05). Significantly lower oral ADL scores were obtained from subjects with delusional ideas, hallucinations, activity disturbances and diurnal rhythm disturbances (p < 0.05), as well as those with affective disturbances (p < 0.01). Conclusion: This study indicated a relationship between BPSD and the wearing of dentures in the elderly with vascular dementia. The study also demonstrated relationships between BPSD and oral ADL. 相似文献
398.
Microscopic characterization of charge carriers in solar cells is useful for high‐performance cell fabrication because the formation and accumulation of charges in cells greatly affect the device performance. Electron spin resonance (ESR) is suitable for such characterization because it can directly observe charge carriers with spins in these cells. In this work, the ESR method is applied to organic thin‐film solar cells to investigate charge formation in such devices. Heterojunction cells of indium tin oxide (ITO)/poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS)/pentacene/C60/bathocuproine (BCP)/Al are investigated. Clear ESR signals are observed by inserting a typical PEDOT:PSS hole buffer layer. From analysis of the dependence of the ESR characteristics on the external magnetic field direction, the bias voltage, and the duration of solar‐simulated irradiation, the charges (mobile holes) in pentacene layers are successfully identified and it can be deduced that these holes are formed at the PEDOT:PSS/pentacene interface during device fabrication. This ESR analysis provides useful knowledge for understanding device operation and improving device performance at the microscopic level. 相似文献
399.
Akira Matsumoto Yasumasa Arai Tomu Kouki Sakae Kikuyama 《Developmental neurobiology》1995,28(1):126-132
Differences in Mauthner (M) cell size were examined in sexually developed and undeveloped male red-bellied newts, Cynops pyrrhogaster. The mean areas of nuclei and cell bodies of M cells and mean maximum and minimum diameters of the cell bodies in the sexually developed males were significantly larger than those in the sexually undeveloped ones. In the hypophysectomized male newts, all these parameters were not significantly different from those in the sexually undeveloped ones. These values were significantly increased by treatment with both bovine prolactin and human chorionic gonadotropin every other day for 3 weeks after hypophysectomy, and these measures were comparable to those in the sexually developed males. These findings suggest that differences in M cell size between sexually developed and undeveloped male newts are due to alteration in hormonal milieu. © 1995 John Wiley & Sons, Inc. 相似文献
400.
Yasumasa Koyama Fumio Kato Shigenobu Oshibi Takeshi Takamatsu Saburo Yamagishi 《Microbiology and immunology》1975,19(5):387-393
The effect of light on the pigmentation of various strains belonging to the genus Streptomyces was investigated. It was revealed that six species of streptomycetes, S. massasporeus, S. phaeopurpureus, S. chibaensis, S. salmonicida, S. fluvissimus and S. longispororuber, were photochromogenic, i.e., these strains can be photoinduced to synthesize pigments. On the basis of these results, pigmentation in Streptomyces is discussed. 相似文献