巻号一覧
67 巻, 5 号
選択された号の論文の15件中1～15を表示しています
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YOSHITAKE MANO, HIROSHI NAGANO1970 年 67 巻 5 号 p. 611-628
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリーAn RNA which stimulates protein synthesis was found to be present in the 12, 000×g precipitate from unfertilized sea urchin eggs when they were fractionated in the presence of Ca2+. Fertilization of the eggs caused translocation of the RNA from the precipitate to the microsomal fraction. A similar translocation was also observed on slight tryptic digestion of the homogenate of unfertilized eggs. In unfertilized eggs, the RNA was released from the precipitate by a brief treatment with trypsin [EC 3. 4. 4. 4] and then polyribosomes seemed to be formed as a result of combination of the RNA and ribo-somes. The RNA resided in specific particles which sedimented in the range of g-values between 8, 000 and 15, 000. The fraction contained also a trypsin-like protease whose activity manifested itself only after fertilization. Nucleic acid analysis revealed the particle to be different from ribosome. The particles were polydisperse and sedimented at 300-400S; they were found to be composed of vesicles in which electron dense particles of uniform size were enclosed. The release of the stored maternal messenger RNA unit from these specific particles by the activation of a trypsin-like protease seems to be a plausible cause of the immediate stimulation of protein synthesis induced by fertilization. The released maternal messenger RNA unit is believed to be a ribonucleo-protein particle which sediments in a polydisperse state at 20-60 S. The activation of the protease mentioned above was temporary, suggesting that it is an event triggering the chain of processes of protein synthesis that follows.抄録全体を表示PDF形式でダウンロード (2997K) -
YOICHI ENDO1970 年 67 巻 5 号 p. 629-633
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリーThe color reaction of orcinol reagent for DNA* has been investigated. DNA re-acted with the orcinol reagent much faster than RNA, and a color with an absorption maximum at 600mμ was developed within a few minutes. The color intensity at 600mμ became the maximum in 2 min after the reaction. The maximum of the absorption spectrum of the color developed in the early stage gradually shifted to 665 mμ. The reaction in the early stage was found to take place by the 2-deoxy-D-ribose in DNA molecules, and the color intensity was proportional to the amount of DNA. The ratio of EDNA665mμ, 15min to EDNA600mμ, 2min was constant. This constancy provides a simple method for an evaluation of purity of DNA preparations and it is applicable to the simultaneous estimation of DNA and RNA in the mixture of them. The mechanism of DNA-orcinol reaction is discussed.抄録全体を表示PDF形式でダウンロード (297K) -
TAKEO OHASHI, SHUJI UCHIDA, KAZUO NAGAI, HIROSHI YOSHIDA1970 年 67 巻 5 号 p. 635-641
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリーThe brain homogenate of guinea pig was fractionated and the nerve ending frac-tion (synaptosome) was separated. After the nerve ending fraction was treated with hypotonic medium, it was subfractionated into five components.
The activities of Na+, K+-ATPase [EC 3. 6. 1. 3], K+-phospharase and Mg2+, Ca2+-ATPase in each fraction were estimated, and it was found that the subcellular distribu-tion of these three enzymes was quite similar, the highest activities of all three being present in the same membraneous fraction which is considered to be mainly composed of the synaptic membrane. The optimal concentration of CaCl, for ATP hydrolysis in the presence of 2 msi MgCl2 and 10-4 M EGTA was about 8×10-5M. The physiological significance of these three enzymes in the membranes is discussed.抄録全体を表示PDF形式でダウンロード (1391K) -
MICHIO OGURA, KAZUMI YAMASAKI1970 年 67 巻 5 号 p. 643-653
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリー3β-Stearyl-7α-hydroxycholesterol labeled with 14C was prepared and its metabolic behavior in rats with a bile-fistula was compared with that of the free diol: i) The stearate, like the free diol was metabolized mainly to cholic and chenodeoxycholic acids and much a-muricholic acid was found in the cholic acid fraction of 6-hr bile samples in both cases; ii) the metabolic pattern, i.e., the ratio of these acids, however, was close to the natural one in short-term experiments.
The distributions of 14C in subcellular fractions of rat liver after administration of 14C-labeled diol and cholesterol were studied. The former was preferentially taken up by the mitochondrial fraction, whereas the latter was largely present in the microsomal fraction.
From these results, the significance of the esterified diol in the catabolism of cholesterol is discussed.抄録全体を表示PDF形式でダウンロード (599K) -
KAZUO NAGAI, NOBUO TANAKA, HAMAO UMEZANWA1970 年 67 巻 5 号 p. 655-660
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリーThe effect of pluramycin on nucleic acid synthesis in cell-free systems of Escherichia coli B was investigated. DNA synthesis was a little more susceptible to pluramycin than RNA synthesis. DNA polymerase [EC 2. 7. 7. 7] reaction was inhibited by plura-mycin and the effect of pluramycin was independent from the stage of the reaction where the pluramycin was added. The inhibition was reversed by increasing the amount of template DNA but not by magnesium ion, deoxyribonucleoside triphosphates or the enzyme. Difference spectra of pluramycin were obtained by adding DNA, sRNA and synthetic polyribonucleotides. The growth-inhibitory effect of pluramycin against Mycoplasma mycoides var. mycoides was reduced by the addition of DNA. Thus, plura-mycin was proved to bind with DNA and to inhibit DNA and RNA polymerase [EC 2. 7. 7. 7 and 6] reactions.抄録全体を表示PDF形式でダウンロード (326K) -
YOSHIKAZU KURASHINA, YOSHIKI OHBA, DEN'ICHI MIZUNO1970 年 67 巻 5 号 p. 661-665
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリー1. Histone was removed partially from calf thymus nucleohistone, and free phosphate groups not bound to histones on DNA were estimated by the toluidine blue method.
2. The template activities of nucleohistones containing different amounts of histone for DNA dependent RNA polymerase [EC 2. 7. 7. 6] from E. coli B (H) revealed the fact that the amount of RNA synthesized by RNA polymerase is proportional to the amount of free phosphate groups in the template but not to the amount of removed histone.
3. The nearest neighbour frequencies of the RNAs formed with these partially dehistonized nucleohistones using [32P] ATP and the base compositions were closely similar to each other. It was therefore suggested that histones distribute evenly along the DNA chains in the nucleohistone. Furthermore, there was found no remarkable difference in the inhibitory effect between lysine-rich and arginine-rich histones.抄録全体を表示PDF形式でダウンロード (345K) -
YASUO OGAWA1970 年 67 巻 5 号 p. 667-683
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリー1. Ca-accumulating activity of the fragmented frog sarcoplasmic reticulum was usually 160-200 mμmoles Ca/mg protein in its capacity and 3-5×106M-1 in its bind-ing constant. Occasionally, preparations with larger capacity, nearly 300 mμmoles Ca/ mg protein, which were more sensitive to caffeine, were obtained.
2. The properties of frog microsomes, which is mainly composed of the fragmented sarcoplasmic reticulum, were essentially the same as those of rabbit microsomes, although some differences were noticed in their responses to temperature, ADP, or pH. In the presence of high concentrations of ATP, Ca-uptake was carried out in two steps in the presence of an ATP regenerating system. The capacity became maximal at 1μM Mg-ATP and 1mM Mg2+, whereas the rate at 30μM Mg-ATP and 3mM Mg2+.
3. The minimum effective concentration of oxalate was 0.3-0.4mM. The time course of Ca-uptake in the presence of oxalate consisted of two phases. The first phase, the rate of which was the same as that in the absence of oxalate, was followed by the second phase with a constant rate determined by the oxalate concentration.
4. The effect of Pi on the Ca-uptake was not simply ascribed to the formation of insoluble salts.
5. Caffeine released Ca rapidly from fragmented frog sarcoplasmic reticulum. Careleasing action of caffeine was more effective in the heavier fraction (1, 200-7, 000×g) than the lighter fraction (7, 000-54, 500×g), and at lower temperatures. The effect of caffeine was counteracted by procaine. These agreed with the results of Weber and Herz. In contrast to the result of Weber there was no difference in the effect of caffeine between 10μM and 0.4mM ATP. The effect of caffeine was dependent on the time when caffeine was added.
6. Thymol showed essentially the same effect as that of caffeine, but was about thirty times as effective as caffeine.
7. The mechanism of action of caffeine was discussed. It was considered to be the releaser of accumulated Ca rather than the inhibitor of Ca-uptake.抄録全体を表示PDF形式でダウンロード (858K) -
I. Roles of the Pancreas and Adrenals in Regulation of Liver Serine Dehydratase ActivityEIJI ISHIKAWA, KATSUYUKI NAKAJIMA1970 年 67 巻 5 号 p. 685-692
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリーOn progressive removal of the pancreas, the liver serine dehydratase [EC 4. 2. 1. 13] activity decreased in parallel to about one-tenth of the normal level on total pancrea-tectomy. The enzyme activity in pancreatectomized rats was not increased in response to treatments such as fasting, force-feeding of amino acids and hydrocortisone adminis-tration, which all caused, more or less, enhancement of the enzyme activity in sham-operated rats. Thus a pancreatic hormone (s) seemed to be involved in control of liver serine dehydratase activity. Glucagon was demonstrated to participate in elevating the enzyme activity in pancreatectomized rats and hydrocortisone was shown to play a “permissive” role, potentiating the induction of serine dehydratase by glucagon.抄録全体を表示PDF形式でダウンロード (544K) -
TOHRU KANAZAWA, MASAYUKI SAITO, YUJI TONOMURA1970 年 67 巻 5 号 p. 693-711
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリーA simple mixing apparatus driven by solenoids was devised to follow a rapid reaction. The partial reactions of Na+-K+ dependent ATPase [ATP phosphohydrolase, EC 3. 6. 1. 3] were separately investigated in the presence of 1mM. MgCl2, and monovalent salts at pH 8.5 and 15°C, and the following results were obtained.
1. When the phosphorylation reaction was stopped by adding excess EDTA to the reaction medium, the concentration of phosphorylated protein, [EP], decreased exponentially with time. The first-order rate constant of the decrease in EP, kd, increased with increase in KC1 concentration (0.50 and 2.26 sec-1, respectively, in the absence and presence of 0.6 mM KCl), and was independent of the concentrations of NaCl and ATP. The rate constant, kd, of the decrease in E32P after the addition of excess unlabelled ATP was essentially the same as that observed after the addition of EDTA.
2. The ratio of the rate of ATP hydrolysis to the EP concentration in the steady state, vo/[EP], increased markedly with increase in KCl concentration (0.57 and 4.43 sec-1, respectively, in the absence and presence of 0.6mM KCl), but was unaffected by changing the ATP concentration. In general, the ratio, vo/[EP], differed from kd . It was nearly equal to kd in the absence of KCl, but it increased more rapidly than ka with increase in the KCl concentration. In the presence of 0.6 met KCl, it was twice kd.
3. The amounts of Pi liberated after the interruption of the phosphorylation reaction by the addition of EDTA were about 1.2 and 2.2 times those of the decrease in EP concentration in the absence and presence of 0.6mM KCl, respectively.
4. The observed time-course of Pi-liberation in the initial phase was in good agreement with that calculated from the observed time-course of EP formation, assuming that EP is an intermediate in the reaction and that its specific turnover rate is equal to the observed value of vo/[EP] in the steady state.
5. Guggenheim plots of EP formation in the presence of 140mM NaCl gave straight lines at a moderate concentration of ATP. The first-order rate constants calculated from the slopes were 2.6 and 4.3 sec-1, respectively, in the absence and presence of 0.6 met KCl. Even at fairly low concentrations of ATP (0.17 and 0.057μs), EP formation proceeded linearly with time without showing any measurable lag phase (less than 0.05 sec). A Lineweaver-Burk plot of the initial rate of EP formation gave a straight line over a low concentration range of ATP. The maximum rate of EP formation, Vf and the Michaelis constant, Kf, obtained from the line were 2.36 moles EP/107g sec and 3.6μM, respectively, in the presence of 140mM NaCl. At higher concentrations of ATP, the double reciprocal plot of the initial rate against [ATP] showed downward deviation from a straight line. The initial rate with 500μM ATP was higher than 15.7 moles EP/107g sec.
6. The rate of EP formation decreased markedlyith decrease in NaCl concentration. The maximum rate of EP formation, Vf, in the presence of 0.5mM NaCl was 0.15 moles EP/107g see, which was much lower than the value, 2.36 moles/107g sec, in the presence of 140mM NaCl. The value of Kf remained constant over a wide range of the NaCl concentrations.
7. The enzyme was incubated with AT32P in the absence of NaCl, and then an NaCl-EDTA mixture was added. The amount of EP increased only slightly after addition of the NaCl-EDTA mixture, though it increased significantly in the presence of NaCl without EDTA抄録全体を表示PDF形式でダウンロード (1160K) -
MICHIKO MURAMATSU, KAICHI AMBO, TSUNEYUKI TSUDA1970 年 67 巻 5 号 p. 727-729
発行日: 1970/05/25
公開日: 2008/11/18
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TOSHIO ASAKURA, KAZUHIKO ADACHI, HARUHISA YOSHIKAWA1970 年 67 巻 5 号 p. 731-733
発行日: 1970/05/25
公開日: 2008/11/18
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TAKAYUKI OZAWA, NAOKI YAMANAKA, MASAKO HAGIHARA, KUNIO YAGI1970 年 67 巻 5 号 p. 737-739
発行日: 1970/05/25
公開日: 2008/11/18
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Incorporation of Radioactive Heme to the Cytochrome in vitroTOSHIHIKO HARA, SHIGEKI MINAKAMI1970 年 67 巻 5 号 p. 741-743
発行日: 1970/05/25
公開日: 2008/11/18
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MASAHIKO NEGISHI, TSUNEO OMURA1970 年 67 巻 5 号 p. 745-747
発行日: 1970/05/25
公開日: 2008/11/18
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NAOKI HIGASHI, HIROHUMI SHOUN, KEITARO HIROMI, KEIJI YANO, KEI ARIMA1970 年 67 巻 5 号 p. 749-752
発行日: 1970/05/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (817K)
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