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991.
Summary Changes in nuclear histone content in differentiating root cells of barley and garlic have been studied by cytochemical methods. The results obtained indicate that the nuclear histones in cell nuclei found in their terminal stages of cellular differentiation or elongation contain histones rich in arginine, whereas the nuclear histones of cell nuclei found in meristem contain histones rich in lysine. Intermediate or transitional types of nuclear histones were also observed in cell nuclei which were undergoing differentiation or elongation and in chromosomes of mitotic cells.Contribution from the Division of Genetics and Cytology, Department of Botany, University of Tokyo, No. 395. 相似文献
992.
Akio Suemori Kenji Nakajima Ryuichiro Kurane Yoshihiro Nakamura 《FEMS microbiology letters》1994,120(1-2):177-181
Abstract p-Hydroxybenzoate 3-hydroxylase from Rhodococcus erythropolis was inactivated by 2,3-butanedione (BD), phenylglyoxal (PGO), and other chemical reagents. p -Hydroxybenzoate and NADH protected the enzyme from inactivation by BD. Judging from the amino acid composition of BD-treated enzyme in the presence and absence of p -hydroxybenzoate, one essential arginine residue in substrate-binding domain of the enzyme was shown to be essential to the binding of p -hydrozybenzoate to the enzyme. Salicylate 5-hydroxylase and m -hydroxybenzoate 6-hydroxylase from R. erythropolis were hardly inactivated. Neither of these two enzymes was considered to have a functional arginine residue required for interaction with the substrate. 相似文献
993.
Akio Tada Hiroshi Sasaki Junji Nakamura Makoto Yoshihama Yoshiteru Terashima 《The Journal of steroid biochemistry and molecular biology》1993,44(4-6):661-666
Human endometrial and breast carcinoma cell lines were examined for aromatase activity and the effects of sex steroids (estradiol and testosterone) on DNA synthesis. Aromatase activity was high (greater than 500 fmol/107 cells/24 h) in the cell lines MCF-7 and OMC-2, moderate (100–499 fmol/107 cells/24 h) in the cell lines HEC-59 and Ishikawa, and low (less than 100 fmol/107 cells/24 h) in the HHUA cell line. A substantial stimulation of DNA synthesis by estradiol (10−9M) was observed in cell lines HEC-59, OMC-2, and MCF-7, with an increase in [3H]thymidine uptake of over 250%. The Ishikawa cell line was stimulated moderately (115–249%). No estradiol-induced increase in DNA synthesis was observed in HHUA. Responsiveness of DNA synthesis to testosterone was observed in cell lines that showed the greatest response to estradiol, namely HEC-59, OMC-2, and MCF-7. Otherwise, estrogen-responsiveness did not always correlate with a significant aromatase activity. These data suggest that some but not all endometrial carcinomas may possess an aromatase-dependent growth stimulating system. 相似文献
994.
995.
996.
Eri Imagawa Hitoshi Osaka Akio Yamashita Masaaki Shiina Eihiko Takahashi Hideo Sugie Mitsuko Nakashima Yoshinori Tsurusaki Hirotomo Saitsu Kazuhiro Ogata Naomichi Matsumoto Noriko Miyake 《Human genetics》2014,133(2):225-234
Leigh syndrome (LS) is an early-onset progressive neurodegenerative disorder characterized by unique, bilateral neuropathological findings in brainstem, basal ganglia, cerebellum and spinal cord. LS is genetically heterogeneous, with the majority of the causative genes affecting mitochondrial malfunction, and many cases still remain unsolved. Here, we report male sibs affected with LS showing ketonemia, but no marked elevation of lactate and pyruvate. To identify their genetic cause, we performed whole exome sequencing. Candidate variants were narrowed down based on autosomal recessive and X-linked recessive models. Only one hemizygous missense mutation (c.665G>C, p.W222S) in glycogenin-2 (GYG2) (isoform a: NM_001079855) in both affected sibs and a heterozygous change in their mother were identified, being consistent with the X-linked recessive trait. GYG2 encodes glycogenin-2 (GYG2) protein, which plays an important role in the initiation of glycogen synthesis. Based on the structural modeling, the mutation can destabilize the structure and result in protein malfunctioning. Furthermore, in vitro experiments showed mutant GYG2 was unable to undergo the self-glucosylation, which is observed in wild-type GYG2. This is the first report of GYG2 mutation in human, implying a possible link between GYG2 abnormality and LS. 相似文献
997.
Effects of Different Types of Bedding Materials on Behavioral Development in Laboratory CD1 Mice (Mus musculus) 下载免费PDF全文
Toyohito Tanaka Akio Ogata Akiko Inomata Dai Nakae 《Birth defects research. Part B, Developmental and reproductive toxicology》2014,101(5):393-401
Male and female mice were housed in cages, containing different types of bedding materials (wood flakes or pulp chips), from 4 weeks of age in the F0 generation to 11 weeks of age in the F1 generation; selected reproductive and neurobehavioral parameters were measured in the F1 generation. There were no adverse effects of bedding materials on litter size, litter weight, or sex ratios at the time of birth. With regard to behavioral development parameters, bedding materials did not influence any variables (p > 0.05) in both sexes. Regarding exploratory behavior in the F1 generation, number of defecations significantly varied (p = 0.0203) with bedding materials in males at 3 weeks of age. The number of horizontal activities also significantly varied (p = 0.0342) with bedding materials in males at 8 weeks of age. Multiple‐T water maze performance data indicated that the time required was significantly shortened across trials in pulp chips group than wood flakes group in males (p = 0.0211). Moreover, all spontaneous behavior variables in males significantly varied with bedding materials, particularly the average time of movement was significantly different (p = 0.0037) in distance between parallel lines of types of bedding materials in the F1 generation. The present study shows that bedding materials influence the neurobehavioral development in mice 相似文献
998.
Upasana Sridharan Akio Ebihara Seiki Kuramitsu Shigeyuki Yokoyama Thirumananseri Kumarevel Karthe Ponnuraj 《Extremophiles : life under extreme conditions》2014,18(6):973-985
Dihydrodipicolinate synthase (DHDPS, E.C.4.2.1.52) catalyzes the first committed step in the lysine biosynthetic pathway: the condensation of (S)-aspartate semialdehyde and pyruvate to form (4S)-4-hydroxy-2,3,4,5-tetrahydro-(2S)-dipicolinic acid. Since (S)-lysine biosynthesis does not occur in animals, DHDPS is an attractive target for rational antibiotic and herbicide design. Here, we report the crystal structure of DHDPS from a hyperthermophilic bacterium Aquifex aeolicus (AqDHDPS). l-Lysine is used as an important animal feed additive where the production is at the level of 1.5 million tons per year. The biotechnological manufacture of lysine has been going for more than 50 years which includes over synthesis and reverse engineering of DHDPS. AqDHDPS revealed a unique disulfide linkage which is not conserved in the homologues of AqDHDPS. In silico mutation of C139A and intermolecular ion-pair residues and the subsequent molecular dynamics simulation of the mutants showed that these residues are critical for the stability of AqDHDPS tetramer. MD simulations of AqDHDPS at three different temperatures (303, 363 and 393 K) revealed that the molecule is stable at 363 K. Thus, this structural and in silico study of AqDHDPS likely provides additional details towards the rational and structure-based design of hyper-l-lysine producing bacterial strains. 相似文献
999.
Olefin saturation and acid reduction of 3,4-dimethoxycinnamic acid and derivatives by Phanerochaete chrysosporium 总被引:1,自引:0,他引:1
The white rot fungus Phanerochaete chrysosporium metabolized 3,4-dimethoxycinnamic acid in shaking and nitrogen sufficient cultures. Metabolites identified included 3-(3,4-dimethoxyphenyl)propionic acid, dimethoxycinnamyl alcohol and 3-(3,4-dimethoxyphenyl)- 1-propanol. Significantly smaller amounts of veratryl and vanillyl alcohol were also present. The abundance of the propionic acid and the propanol as metabolic products indicate that olefin saturation and acid reduction are important reactions catalysed under these conditions. Metabolites identified from the metabolism of 3-(3,4-dimethoxyphenyl)-propionic acid included the above 1-propanol as well as veratryl and vanillyl alcohol; the identification of these benzyl alcohol derivatives as metabolites suggests that α,β-bond cleavage of this substrate was preceded by alkane hydroxylation at the α-position. 相似文献
1000.
Effect of inositol hexaphosphate on hemoglobin oxidation by nitrite and ferricyanide 总被引:1,自引:0,他引:1
Akio Tomoda Shigeru Matsukawa Masazumi Takeshita Yoshimasa Yoneyama 《Biochemical and biophysical research communications》1977,74(4):1469-1474
In the presence of inositol hexaphosphate (IHP), the rate of hemoglobin oxidation by nitrite was much inhibited; however, that of the hemoglobin oxidation by ferricyanide was much accelerated. The difference in the reaction mode was discussed in relation to the interaction of hemoglobin with IHP. The dissociation constant of IHP to oxyhemoglobin was estimated from the rate of the hemoglobin oxidation by ferricyanide in different concentrations of IHP under oxygen saturated conditions. 相似文献