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21.
Three growth inhibitors which might be involved in phototropism of Sakurajima radish (Raphanus sativus var. hortensis f. gigantissimus Makino) hypocotyls, were isolated as crystalline forms from light-exposed radish seedlings and identified as cis- and trans-raphanusanins and 6-methoxy-2,3,4,5-tetrahydro-1,3-oxazepin-2-one (designated raphanusamide). The cis- and trans-raphanusanins inhibited growth of etiolated radish hypocotyls at concentrations higher than 1.5 micromolar, raphanusamide at concentrations higher than 20 micromolar. 相似文献
22.
Ryuji Fukuda Ryoji Yano Toshikazu Fukui Toshiharu Hase Akira Ishihama Hiroshi Matsubara 《Molecular & general genetics : MGG》1985,201(2):151-157
Summary In order to clone the Escherichia coli gene for the stringent starvation protein (SSP), we determined its N-terminal sequence as well as the sequence of two peptide fragments obtained by cyanogen bromide cleavage of the protein. We then chemically synthesized four sets of oligodeoxyribonucleotide mixtures that represented possible codon combinations for parts of these amino acid sequences. The synthetic oligonucleotides were labelled with 32P at their 5-termini and used as hybridization probes to detect DNA fragments containing the complementary sequences. Genomic Southern hybridization of E. coli chromosomal DNA gave up to ten DNA fragments hybridizing with each probe but only a few hybridized with two or more of the probes. The latter fragments were coloned in pBR322. By determining partial base sequences with a rapid method and examining proteins encoded by the DNA fragments, we were able to show that we had isolated a clone containing the complete SSP structural gene.Abbreviations SSP
stringent starvation protein
- PTH
phenylthiohydantoin 相似文献
23.
Human C3, the third component of human complement, contained mannose and N-acetylglucosamine as sugar components. The sugar chains were liberated from the polypeptide chains by hydrazinolysis, and the free amino groups were N-acetylated. The reducing end residues of the sugar chains thus obtained were tagged with 2-aminopyridine, and the pyridylamino (PA-) derivatives of sugar chains were separated by high-performance liquid chromatography. The structures of purified PA-sugar chains were analyzed by a combination of stepwise exoglycosidase digestions, size determination by paper electrophoresis, methylation analysis, Smith degradation, and partial acetolysis. These results showed that C3 contained two high-mannose type sugar chains ranging from Man5GlcNAc2 to Man9GlcNAc2. Analyses of the sugar chains of alpha- and beta-chains of C3 indicated that the alpha-chain contained mainly Man8GlcNAc2 and Man9GlcNAc2, while the beta-chain contained mainly Man5GlcNAc2 and Man6GlcNAc2. 相似文献
24.
Akira Inokuchi Yasunobu Tomida Chizuko Yanaihara Ryogo Yui Yutaka Oomura Hiroshi Kimura Takanobu Hase Tomoaki Matsumoto Noboru Yanaihara 《Cell and tissue research》1986,246(1):71-75
Summary Immunohistochemically, nerve fibers and terminals reacting with anti-N-terminal-specific but not with anti-C-terminal-specific glucagon antiserum were observed in the following rat hypothalamic regions: paraventricular nucleus, supraoptic nucleus, anterior hypothalamus, arcuate nucleus, ventromedial hypothalamic nucleus and median eminence. Few fibers and terminals were demonstrated in the lateral hypothalamic area and dorsomedial hypothalamic nucleus. Radioimmunoassay data indicated that the concentration of gut glucagon-like immunoreactivity was higher in the ventromedial nucleus than in the lateral hypothalamic area. In food-deprived conditions, this concentration increased in both these parts. This was also verified in immunostained preparations in which a marked enhancement of gut glucagon-like immunoreactivity-containing fibers and terminals was observed in many hypothalamic regions. Several immunoreactive cell bodies were found in the ventromedial and arcuate nuclei of starved rats. Both biochemical and morphological data suggest that glucagon-related peptides may act as neurotransmitters or neuromodulators in the hypothalamus and may be involved in the central regulatory mechanism related to feeding behavior and energy metabolism. 相似文献
25.
K Nakahama K Yoshimura R Marumoto M Kikuchi I S Lee T Hase H Matsubara 《Nucleic acids research》1986,14(14):5843-5855
The gene encoding an extracellular metalloproteinase from Serratia sp. E-15 has been cloned, and its complete nucleotide sequence determined. The amino acid sequence deduced from the nucleotide sequence reveals that the mature protein of the Serratia protease consists of 470 amino acids with a molecular weight of 50,632. The G+C content of the coding region for the mature protein is 58%; this high G+C content is due to a marked preference for G+C bases at the third position of the codons. The gene codes for a short pro-peptide preceding the mature protein. The Serratia protease gene was expressed in Escherichia coli and Serratia marcescens; the former produced the Serratia protease in the cells and the latter in the culture medium. Three zinc ligands and an active site of the Serratia protease were predicted by comparing the structure of the enzyme with those of thermolysin and Bacillus subtilis neutral protease. 相似文献
26.
Takahashi Yasuhiro; Hase Toshiharu; Wada Keishiro; Matsubara Hiroshi 《Plant & cell physiology》1983,24(2):189-198
An antibody for ferredoxin was used to investigate the developmentof ferredoxin during the greening of spinach cotyledons. Ferredoxinwas present in 8-day-old etiolated cotyledons and increasedwith illumination, which means that the synthesis of ferredoxinwas both light dependent and independent. The ferredoxin purified from etiolated cotyledons, greeningcotyledons, and mature leaves was a mixture of two chemicallydistinct molecular species; ferredoxin I and II. The relativecontents of these two species varied with the stage of developmentand the conditions used. Ferredoxin I was identical with that isolated previously asvalidated by its amino acid sequence [Matsubara and Sasaki (1968)J. Biol. Chem. 243: 1732]. The complete amino acid sequenceof the second component, ferredoxin II, was determined as well.It was composed of 97 amino acid residues and differed fromferredoxin I by 25 residues. (Received October 16, 1982; Accepted December 14, 1982) 相似文献
27.
28.
Social changes of Japanese monkey troops in the Takasakiyama 总被引:1,自引:0,他引:1
Hiroki Mizuhara 《Primates; journal of primatology》1964,5(1-2):27-52
29.
Immunogold Localization of Ribulose-1,5-Bisphosphate Carboxylase with Reference to Pyrenoid Morphology in Chloroplasts of Synchronized Euglena gracilis Cells 总被引:1,自引:0,他引:1 下载免费PDF全文
Euglena gracilis strain (Z) cells were synchronized under photoautotrophic conditions using a 14 hour light:10 hour dark regimen. The cells grew during the light period (growth phase) and divided during the following 10 hour period either in the dark or in the light (division phase). Changes in morphology of the pyrenoid and in the distribution of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) within the chloroplasts were followed by immunoelectron microscopy during the growth and division phases of Euglena cells. Epon-embedded sections were labeled with an antibody to the holoenzyme followed by protein A-gold. The immunoreactive proteins were concentrated in the pyrenoid, and less densely distributed in the stroma during the growth phase. During the division phase, the pyrenoid could not be detected and the gold particles were dispersed throughout the stroma. Toward the end of the division phase, the pyrenoid began to form in the center of a chloroplast, and the immunoreactive proteins started to concentrate over that rudimentary pyrenoid. During the growth phase, small areas rich in gold particles, called `satellite pyrenoid,' were observed, in addition to the main pyrenoid. From a comparison of photosynthetic CO2-fixation with the total carboxylase activity of Rubisco extracted from Euglena cells in the growth phase, it is suggested that the carboxylase in the pyrenoid functions in CO2-fixation in photosynthesis. 相似文献
30.
K Miyamoto K Hase Y Taketani H Minami T Oka Y Nakabou H Hagihira 《Biochemical and biophysical research communications》1992,183(2):626-631
Developmental changes in glucose transporter mRNA levels in the jejunum of rats of different ages were examined by using slot blot RNA analysis. The level of SGLT1 mRNA did not change significantly through life. The GLUT5 mRNA level was highest in 10-day-old rats and then decreased reaching the adult level by day 20 after birth. The GLUT2 mRNA level was low in rats of 5 and 10 days old, but then increased progressively reaching the adult value by day 25 after birth. These results indicate that the expressions of intestinal facilitative glucose transporter genes change markedly in the third week after birth. 相似文献