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1.
A respiration-deficient (RD) mutant was isolated from the petite-negative, salt-tolerant yeast Zygosaccharomyces rouxii. One strain among sixteen glycerol-non-utilizing mutants exhibited vigorous liberation of CO2 but no uptake of O2. Furthermore, this strain lacked cytochrome aa3 and had a reduced level of cytochrome b. The few mitochondria found in cells of this strain contained few or no cristae. Salt tolerance and intracellular accumulation of glycerol by the RD strain were almost equal to that of the wild-type strain in media containing NaCl up to 2.5 M. In media with more than 3 M NaCl, the growth of the RD mutant was retarded and the intracellular accumulation of glycerol was depressed in spite of ample production. 相似文献
2.
Yukio Kitade Naohiro Saito Atushi Kozaki Kazumasa Takahashi Chizuko Yatome Yoshifumi Takeda 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):91-97
Abstract Reaction of 9-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-7-methylguaninium iodide (2a) with hydrogen peroxide in acetic acid gave the corresponding 7-methyl-8-oxoguanosine derivative (3a) in good yield. Deprotection of 3a easily gave 7-methyl-8-oxoguanosine (1), which is well-known as an immunomodulator. Substitution of acetyl group at the N-position of guanine ring accelerated the oxidation reaction of the 7-methylguaninium iodide. 相似文献
3.
Yokono Makio Umetani Ikumi Takabayashi Atushi Akimoto Seiji Tanaka Ayumi 《Photosynthesis research》2019,139(1-3):155-161
Photosynthesis Research - Recently, we isolated a complex consisting of photosystem II (PSII) and light-harvesting complexes (LHCs) from Nannochloropsis granulata (Umetani et al. Photosynth Res... 相似文献
4.
Hajime Sasaki Atushi Nemoto Hisae Kume Sonoko Narisawa Naommy Takahashi 《In vitro cellular & developmental biology. Animal》1998,34(1):68-73
Summary A factor with a molecular weight of less than 1 kDa in the mucosa of the bovine small intestine (low molecular weight factor
or LMW factor) stimulated DNA synthesis in rat hepatocytes in primary culture. This factor only showed its activity when it
was added with a larger factor with a molecular weight of 30 kDa that was also found in the same tissue (high molecular weight
factor or HMW factor). The LMW factor probably acts to enhance the action of a hepatotrophic growth factor, since EGF and
HGF can substitute for the HMW factor. The action of the LMW factor was not due to the actions of low molecular weight substances
such as norepinephrine, estradiol, triiodothyronine, and putrescine, which enhance the action of EGF or HGF, since substantial
amounts of these substances were not found in the extract. When intraperitoneally administered into rats, after two-thirds
hepatectomy, the LMW factor enhanced hepatocyte proliferation without the administration of the HMW factor. In the regenerating
liver, a hepatotrophic growth factor(s), which acts synergistically with the LMW factor, might be properly provided, but the
supply of the LMW factor might be below the level that maximally stimulates hepatocyte proliferation. 相似文献
5.
In the present study, the effect of constituting amino acid residue numbers of oligopeptide derivatives, which are candidate materials to construct molecular recognition sites, on chiral recognition ability was investigated. Chiral recognition sites were formed from oligopeptide derivatives, of which constituting amino acid residue numbers were three to six, by adopting an alternative molecular imprinting. It was made clear that the number four, in other words, the tetrapeptide derivative, is the best candidate material to form a chiral recognition site. 相似文献
6.
Atushi Ushimaru Satoshi Kikuchi Ryuji Yonekura Atsushi Maruyama Nao Yanagisawa Maiko Kagami Michiko Nakagawa Suzuki Mahoro Yukihiko Kohmatsu Aya Hatada Shumpei Kitamura Kensuke Nakata 《Nordic Journal of Botany》2004,24(5):593-598
We compared the amount of variation in flower size between autogamous and insect-pollinated species to examine the hypothesis that pollinator-mediated selection stabilizes flower size in plant populations. One would expect the flower size variation to be larger in selfing species that are less affected by pollinator-mediated stabilizing selection than in insect-pollinated species. The results of phylogenetic comparisons between autogamous and insect-pollinated flowers supported the pollinator-mediated stabilizing selection hypothesis, although the non-phylogenetic comparison did not. According to our results, we discuss the factors influencing the flower size variation. 相似文献
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8.
Shiina T Dijkstra JM Shimizu S Watanabe A Yanagiya K Kiryu I Fujiwara A Nishida-Umehara C Kaba Y Hirono I Yoshiura Y Aoki T Inoko H Kulski JK Ototake M 《Immunogenetics》2005,56(12):878-893
Salmonid fishes are among the few animal taxa with a probable recent tetraploid ancestor. The present study is the first to compare large (>100 kb) duplicated genomic sequence fragments in such species. Two contiguous stretches with major histocompatibility complex (MHC) class I genes were detected in a rainbow trout BAC library, mapped and sequenced. The MHC class I duplicated regions, mapped by fluorescence in situ hybridization (FISH), were shown to be located on different metaphase chromosomes, Chr 14 and 18. Gene organization in both duplications is similar to that in other fishes, in that the class I loci are tightly linked with the PSMB8, PSMB9, PSMB10 and ABCB3 genes. Whereas one region, Onmy-IA, has a classical MHC class I locus (UBA), Onmy-IB encodes only non-classical class Ib proteins. The nucleotide diversity between the Onmy-IA and Onmy-IB noncoding regions is about 14%. This suggests that the MHC class I duplication event has occurred about 60 mya close to the time of an hypothesized ancestral tetraploid event. The present article is the first convincing report on the co-existence of two closely related MHC class I core regions on two different chromosomes. The interchromosomal duplication and the homology levels are supportive of the tetraploid model.Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank database under the accession numbers AB162342, AB162343 and from AY525774 to AY525776. 相似文献
9.
Takahiro Kuragano Kenichiro Kitamura Osamu Matsumura Akihiko Matsuda Taiga Hara Hideyasu Kiyomoto Toshiaki Murata Shouichi Fujimoto Hiroki Hase Nobuhiko Joki Atushi Fukatsu Toru Inoue Yukihiro Itakura Takeshi Nakanishi 《PloS one》2016,11(3)
Objective
It has been reported that hyporesponsiveness to erythropoiesis-stimulating agent (ESA) is associated with adverse events in patients on maintenance hemodialysis (MHD). However, it has not been determined whether higher iron storage is associated with an improved response, including better survival, to ESA.Design and Method
We measured serum ferritin, hemoglobin (Hb), and transferrin saturation (TSAT) levels every three months for two years in 1,095 MHD patients. The weekly dose of ESA to Hb ratio was also calculated as an index of ESA responsiveness (ERI).Results
A significant correlation (p<0.001, R = 0.89) between ferritin and Hb was only observed in the patients with ferritin levels <50 ng/mL. High-dose (≥50 mg/week) intravenous iron administration, female sex, low serum albumin, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use were significant predictors of a high ERI value (>280); however, serum ferritin and TSAT levels did not predict a higher ERI. In the time-dependent Cox hazard model, the risk for a composite event in the patients with a high ERI (≥280) and a high ferritin level (≥100 ng/mL) was significantly greater (hazard ratio [HR], 2.09, P = 0.033) than that for patients with a high ERI and a low ferritin (<100 ng/mL) level.Conclusion
Hb was dependent upon ferritin levels in patients with ferritin levels <50 ng/mL but not in patients with ferritin levels ≥50 ng/mL. Patients with hyporesponsiveness to ESA had a greater risk of composite events, but ERI was unrelated to iron storage. 相似文献10.
Keimei Oh Tadashi Matsumoto Ayumi Yamagami Atushi Ogawa Kazuhiro Yamada Ryuichiro Suzuki Takayuki Sawada Shozo Fujioka Yuko Yoshizawa Takeshi Nakano 《PloS one》2015,10(3)
Plant hormone brassinosteroids (BRs) are a group of polyhydroxylated steroids that play critical roles in regulating broad aspects of plant growth and development. The structural diversity of BRs is generated by the action of several groups of P450s. Brassinazole is a specific inhibitor of C-22 hydroxylase (CYP90B1) in BR biosynthesis, and the application use of brassinazole has emerged as an effective way of complementing BR-deficient mutants to elucidate the functions of BRs. In this article, we report a new triazole-type BR biosynthesis inhibitor, YCZ-18. Quantitative analysis the endogenous levels of BRs in Arabidopsis indicated that YCZ-18 significantly decreased the BR contents in plant tissues. Assessment of the binding affinity of YCZ-18to purified recombinant CYP90D1 indicated that YCZ-18 induced a typical type II binding spectrum with a Kd value of approximately 0.79 μM. Analysis of the mechanisms underlying the dwarf phenotype associated with YCZ-18 treatment of Arabidopsis indicated that the chemically induced dwarf phenotype was caused by a failure of cell elongation. Moreover, dissecting the effect of YCZ-18 on the induction or down regulation of genes responsive to BRs indicated that YCZ-18 regulated the expression of genes responsible for BRs deficiency in Arabidopsis. These findings indicate that YCZ-18 is a potent BR biosynthesis inhibitor and has a new target site, C23-hydroxylation in BR biosynthesis. Application of YCZ-18 will be a good starting point for further elucidation of the detailed mechanism of BR biosynthesis and its regulation. 相似文献