巻号一覧
61 巻, 5 号
選択された号の論文の18件中1～18を表示しています
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I. Crystallization and PropertiesTOMOHIRO MATSUDA, YASUMI YUGARI1967 年 61 巻 5 号 p. 535-540
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーGlucose-6-phosphate dehydrogenase [EC 1. 1. 1. 49] was purified from rat liver and crystallized.
The crystalline enzyme was ultracentrifugally pure and its molecular weight was determined by ultracentrifugation to be 110, 000.
The differences between the enzymes from the liver and the erythro-cytes in their dietary responses, kinetics and immunochemical properties were discussed.抄録全体を表示PDF形式でダウンロード (1370K) -
II. Effect of Diet on Enzyme Activity in vivo, and Inhibition by Long Chain Fatty Acids in vitroYASUMI YUGARI, TOMOHIRO MATSUDA1967 年 61 巻 5 号 p. 541-549
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーThe rat liver glucose-6-phosphate dehydrogenase [EC 1. 1. 1. 49] activity was increased on re-feeding animals after two days of fasting. The extent of the increment in the enzyme activity was inversely related to the fat content of the diet. Dietary experiments indicated that unsaturated fatty acids were more effective than saturated fatty acids in suppressing the enzyme induction.
Glucose-6-phosphate dehydrogenase purified from rat liver was in-hibited by the free fatty acids, myristic, lauric and palmitic acids in decreasing order.
Glucose-6-phosphate dehydrogenase was specifically protected from the inhibition by free fatty acids in the presence of NADP, and, to a lesser extent, in the presence of glucose 6-phosphate. ATP, GTP and ITP facilitated the inhibitory effect of fatty acids, and the effect of ATP was abolished by ADP or AMP. The facilitatory effect of ATP was more significant at high pH values. The transition temperature of glucose-6-phosphate dehydrogenase was markedly lowered by free fatty acids or ATP and elevated by NADP. Free fatty acid disaggregated the active enzyme into inactive subunits.
The inhibition of glucose-6-phosphate dehydrogenase in vivo by free fatty acids was discussed and it was suggested that the fatty acid synthesis was controlled in two ways by free fatty acids: one by inhibiting acetyl-CoA carboxylase [EC 6. 4. 1. 2], and the other by restricting the supply of NADPH through the inhibition of glucose-6-phosphate dehydrogenase.抄録全体を表示PDF形式でダウンロード (711K) -
MASACHIKA IRIE1967 年 61 巻 5 号 p. 550-554
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリー1. Kinetic parameters, Km and Vmax, of RNase T1 [EC 2. 7. 7. 26] were obtained using G-cyclic-p as substrate at various pH's. From the pKm-, log Vmax- pH profile, two pKa's of free enzyme (pKe) and pKa of enzyme-substrate complex (pKes) were estimated (pKe 5.7 and about 7.5; pKes 3.7, 6.7 and about 7.4).
2. From the pKi pH profile of RNase T1 using G-2'-p as competitive inhibitor, the pKe values of 5.7 and about 7.5 were also obtained.
3. Based on the values obtained above, the possibility of the presence of histidine residues in the active site of the enzyme was discussed.
4. From the pKi- and pKm-pH profile, the preferable binding form of G-2'-p with the enzyme was presumed to be monoanionic species.抄録全体を表示PDF形式でダウンロード (394K) -
TOHRU KANAZAWA, MASAYUKI SAITO, YUJI TONOMURA1967 年 61 巻 5 号 p. 555-566
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリー1. The dependence of Na+-K+ sensitive ATPase [EC 3. 6. 1. 3] ac-tivity on temperature was investigated between 0° and 40°C. The Arrhenius plot of the total activity of a system containing Mg++, Na+ and K+ ions consisted of two linear portions which intersected at about 25°C. The experimental activation energies calculated from the plot were 29.5 kcal per mole in the low temperature range (0°-25°C) and 18.4 kcal per mole in the high temperature range (25°-40°C). The Arrhenius plot of the system containing Mg++ and Na+ ions was linear with an activation energy of 16.3 kcal per mole over the entire temperature range (0°-40°C).
2. The dependence of ATPase activity at the steady state on the ATP concentration was measured at 10°C. At high ATP concentrations, the activity of the system containing Mg++, Na+ and K+ ions (Mg-Na-K ATPase activity) was much higher than that of the system containing Mg++ and Na+ ions (Mg-Na ATPase activity). But the former decreased rapidly with reduction in the ATP concentration, becoming much lower than the latter, and reached the level of the activity of the system containing Mg++ alone (Mg ATPase activity) at extremely low concen-trations of ATP.
3. The Na+-dependent ATPase activity at the steady state (the difference between Mg-Na ATPase activity and Mg ATPase activity) and the amount of Na+-dependent P32-incorporation from ATP32 (γ-P32) into the enzyme were measured simultaneously in the presence of various concentrations of ATP (0.33-10 μM) at 0°C. The amount of P32-in-corporation was 1.23 moles per 107g. of protein at 101μM ATP and diminished with decrease in the concentration of ATP. The rate of ATPase activity was always lower than the initial rate of P32-incorporation. The difference between these two rates became greater as the ATP concentration became lower. Furthermore, the apparent Michaelis con-stant of the ATPase activity (1.8μM) was very different from that of P32-incorporation (0.31μM). From these results, it was concluded that the P32-incorporation observed at 0°C cannot be due to an intermediate of the Na+-dependent ATPase reaction at this temperature.
4. The rate of the ATPase reaction at the steady state (v) and the amount of Pat-incorporation ([E_??_P]) were measured simultaneously in the presence of various concentrations of KCl (0-28mM) and a fixed concentration of NaCl (140mM) at 37°C. The following two relations were observed:
Here, V and A are constants and s indicates the molar concentration of phosphorylation site. Next, the values of v and [E_??_P] were measured simultaneously in the presence of various concentrations of NaCl (0-140mM) and a fixed concentration of KCl (1mM) at 37°C. The value of v was found to be in proportion to [E_??_P] over a wide range of NaCI concentrations. These facts can be explained quantitatively if phosphory-lated enzyme (E_??_P) is an intermediate of the ATPase reaction at 37°C and the ATPase reaction occurs according to the following mechanism:
_??_
5. By comparing the properties of Na+-K+ sensitive ATPase with those of myosin B-ATPase, the following new reaction mechanism is suggested: the Na+-K+ sensitive ATPase is a double headed enzyme, which can hydrolyze ATP by two routes, simple hydrolysis through the Michaelis complex and hydrolysis via phosphorylated enzyme抄録全体を表示PDF形式でダウンロード (800K) -
KAZUKO SEKIYA, KIKUKO TAKEUCHI, YUJI TONOMURA1967 年 61 巻 5 号 p. 567-579
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーThe reaction of the H-meromyosin-F-actin-ATP system was in-vestigated in the presence of various concentrations of ATP, F-actin and KCl in 1mM MgCl2 and 10mM Tris-HCl at pH 7.5 and 25°C. The following results were obtained:
1. The binding ratio of H-meromyosin to F-actin was 3.3:1 by weight. When ATP was added to acto-H-meromyosin, the intensity of light scattered at high angles decreased to a level lower than the sum of those of H-meromyosin and F-actin. The weight average molecular weight of acto-H-meromyosin estimated from the angular distribution was slightly decreased but the z-average radius of gyration was increased markedly by the addition of ATP.
2. The ATP concentration necessary for obtaining half the maximum change in the intensity of light scattered at 90° by acto-H-meromyosin was increased by decrease in the ionic strength and by increase in the F-actin concentration. At a fixed ionic strength, the ATPase [EC 3. 6. 1. 3] activity of acto-H-meromyosin increased monotonously with ATP con-centration and the so called “substrate inhibition” was not observed. The activity in the presence of a sufficient amount of ATP was increased by increase in the F-actin concentration and by decrease in the ionic strength. The ATP concentration necessary for attaining half the maximum activity was increased by decrease in the ionic strength and by increase in the F-actin concentration, and was higher than that for inducing half the maximum change in the intensity of light-scattering. The effect of treatment of H-meromyosin with PCMB and β-mercapto-ethanol on the ATPase activity of acto-H-meromyosin was very similar to that observed when decreasing the ionic strength.
3. The ATPase activity of acto-H-meromyosin was unaffected by the addition of EGTA, but inhibited by the addition of EDTA. The inhibition was restored by the further addition of MgCl2. About 40-80 per cent of ADP of F-actin were exchanged with nucleotide in the medium, when H-meromyosin and ATP were added to F-actin.
4. From these results the following reaction scheme is proposed for the reaction between H-meromyosin, F-actin and ATP:
_??_
where M and A are the binding units of H-meromyosin and F-actin, and S is MgATP--; k1 and k2 are the rate constants of ATP splitting by the myosin type and the actomyosin type ATPase, respectively. AMS* is a complex of acto-H-meromyosin with ATP, which has a weight average molecular weight almost equal to that of AM but a radius of gyration much larger than AM. Furthermore, the polymerization state of F-actin in AMS* is different from F-actin itself.抄録全体を表示PDF形式でダウンロード (973K) -
I. Further Purification of Hog Kidney D-Amino Acid Oxidase and Its Hydrodynamic and Optical Rotatory PropertiesKUNIO YAGI, MAKOTO NAOI, MINORU HARADA, KENTARO OKAMURA, HIROYOSHI HID ...1967 年 61 巻 5 号 p. 580-597
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリー1. Methods for the preparation of the pure benzoate complex, holoenzyme, and apoenzyme of D-amino acid oxidase [EC 1. 4. 3. 3] are described. Chromatography with Sephadex G-75 at pH 8.3 is a satisfactory procedure for further purification of the crystalline benzoate complex prepared by the previous method. Crystalline enzyme is prepared from the gel-eluate by repeated expulsion of benzoate from the complex with an excess amount of D-alanine. The cleavage of the holoenzyme into apoenzyme and FAD is performed on a TEAE-cellulose column equilibrated at pH 5.3.
2. The physico-chemical properties of three species of the oxidase prepared by the method described above are as follows : For the benzoate complex, s020, w=6.3×10-13 sec.-1 D20, w=5.3×10-7cm.2 sec.-1; [η]=0.033 dl. g.-1;_??_=0.742ml. g.-1. For the holoenzyme, s020=7.1×10-13 sec.-1; D020, w=5.8ηl0-7 cm.2sec.-1; [η]=0.026 dl. g. 1. For the apoenzyme, s020, w=3.6×10-13 sec.-1; D20, w=6.2×10-7 cm.2 sec.-1.
From these results, the molecular weights of both the holoenzyme and the benzoate complex are calculated to be 103, 000-134, 000 and that of the apoenzyme to be about 55, 000. These results are not incon-sistent with the minimal molecular weight calculated from the amount of bound FAD, provided the holoenzyme and benzoate complex exist in a dimeric form. It is concluded that the enzyme is a basic protein bearing one molecule of FAD per 50, 000g. of protein.
3. The optical rotatory properties of the apoenzyme in M/60 pyrophosphate buffer (pH 8.3) at 25°C are found to be [α]25D=-47°; λc=236mμ; a0=-240; and b0=-72. These values indicate that it contains about 12% helices. This content is confirmed by the measurement of amplitude of the trough at 233mμ. No significant differences are found in the helical contents of the apoenzyme, the holoenzyme and its benzoate complex.抄録全体を表示PDF形式でダウンロード (3752K) -
II. Terminal Structure and Amino Acid Composition of Hog Kidney D-Amino Acid OxidaseAKIRA KOTAKI, MINORU HARADA, KUNIO YAGI1967 年 61 巻 5 号 p. 598-605
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーGross structure of hog kidney D-amino acid oxidase [EC 1. 4. 3. 3] has been characterized by analyzing both N- and C-terminal residues and amino acid composition. The enzyme has been found to be composed of two methionine chains and two FAD per 100, 000g., and to be fairly rich in tyrosine and tryptophan residues. The C-terminal residue of these methionine chains has been identified to be leucine from the results of hydrazinolysis and carboxypeptidase A digestion. The partial specific volume of the enzyme calculated from the amino acid compo-sition was 0.73 ml./g. which fairly agreed with the value of 0.742ml./g. of the enzyme-benzoate complex previously measured by the usual pycnometer method. The results presented here and in the previous paper were likely to suggest that the enzyme is made up of two identical polypeptide chains.抄録全体を表示PDF形式でダウンロード (1261K) -
BYEONG-KUK SEON1967 年 61 巻 5 号 p. 606-614
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーWhen Taka-amylase A [EC 3. 2. 1. 1] containing one masked sulfhydryl and four disulfide groups was incubated with sodium borohydride at 29_??_30°C in an aqueous solution, titrable sulfhydryl groups increased stepwise as a function of the reduction time. At the first and the second plateaus, two sulfhydryl groups and an additional one group were concluded to be derived from the most labile disulfide bond out of the four and from the masked sulfhydryl group, respectively. The above conclusion was confirmed by preparing radioautograms of the peptic digests of the S-carboxymethylated reduced-amylases, in which the substituent was labeled with C14. Such a stepwise appearance of the sulfhydryl groups was quite sensitive to the protein conformation, and could not be observed when the reduction was carried out at higher temperatures or in the presence of denaturants.抄録全体を表示PDF形式でダウンロード (715K) -
KAYOKO IKEDA1967 年 61 巻 5 号 p. 615-622
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリー1. Mitomycin C-induced formation of pyocin R in Pseudomonas aeruginosa, strain R, is inhibited by low concentrations of p-fluorophenyl-alanine (FPA**). Cell growth proceeds apparently normally in the pres-ence of FPA and mitomycin C, but neither pyocin R nor a protein cross-reacting with anti-pyocin R antibody is accumulated in the cells.
2. FPA inhibits the early stage of induction and this inhibition is reversed by phenylalanine or tyrosine.
3. In the cells treated with both FPA and mitomycin C, DNA synthesis is almost completely inhibited as in the mitomycin C-treated cells. However, RNA and protein synthesis take place almost normally in the former cells. The presence of an FPA-sensitive mechanism specific for pyocin R formation is therefore suggested.
4. Neither the induction of λ phage nor the multiplication of phage in E. coli K12 is inhibited by such concentrations of FPA.抄録全体を表示PDF形式でダウンロード (1362K) -
YOSHIHO NAGATA, ISAO SHIBUYA, BUNJI MARUO1967 年 61 巻 5 号 p. 623-632
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーA membrane system was prepared from Escherichia coli K12 by the treatment with lysozyme [EC 3. 2. 1. 17] and EDTA, followed by osmotic disruption in the presence of 0.005M MgCl2. Electron microscopic observation revealed that the system was composed of cytoplasmic membranes to which an appreciable amount of ribosomes was attached. The ribosomes were released from the system upon washing with a Mg++-free medium.
The system prepared with 0.005M MgCl2 contained about 50% protein, 40% RNA, 30% DNA and 80% phosphatide of the cells. These values, except that of phosphatide, were, however, continuous functions of the concentration of magnesium ions with which the membrane systems were prepared.
The membrane system actively incorporated 3H-leucine into the protein and 32Pi into the RNA and the DNA fractions. Chloramphenicol, actinomycin D and mitomycin C strongly inhibited the incorporation into protein, RNA and DNA, respectively.
Qualitative difference in the membrane-bound and soluble components was investigated. Succinate oxidase system was localized specifically in the membrane, while glucose-6-phosphate dehydrogenase [EC 1. 1. 1.49] was detected only in the supernatant fraction. Hatch's polarity ratios of the bulk proteins were found to be 1.32 for the membrane and 1.57 for the supernatant. As much as 78% of the total phosphatides was found in the membrane system. The major lipids were phosphatidyl ethanolamine and phosphatidyl glycerol in both fractions.
Possibility that the activity of the membrane system would have been attributed to the contaminated intact cells and/or undisrupted spheroplasts was eliminated from several evidences including viable cell counts of the system.抄録全体を表示PDF形式でダウンロード (1856K) -
IXC. Fate of the 4β-Hydrogen of Cholesterol during the Biogenesis of 5α-Bile AlcoholsTAKAHIKO HOSHITA1967 年 61 巻 5 号 p. 633-635
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーThe fate of tritium during the conversion of 4β-3H-4-14C-cholesterol to 5α-bile alcohols in the carp was investigated. The labeled 5a-cyprinol and 27-deoxy-5α-cyprinol isolated from the gall bladder bile had lost most of the administered tritium. This result indicates that the reduc-tion of the double bond of cholesterol takes place after its isomerization from the Δ5 to the Δ4 position.抄録全体を表示PDF形式でダウンロード (173K) -
I. Purification and Properties of Particle-bound Fructose DehydrogenaseYUZO YAMADA, KÔ AIDA, TEIJIRO UEMURA1967 年 61 巻 5 号 p. 636-646
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーAn enzyme, fructose dehydrogenase which catalyzes the oxidation of D-fructose to 5-keto-D-fructose was obtained from fructose-grown cells of Gluconobacter cerinus. The enzyme present in particulate fraction was solubilized by deoxycholate-butanol extraction, and purified about 40-50 fold by acetone precipitation and DEAE-cellulose column chromatography.
2, 6-Dichlorophenol indophenol was the most effective electron acceptor but neither NAD nor NADP was required. The optimal pH was 5.0 and Michaelis constant for D-fructose was 1.0×10-2M in the presence of 6.7×10-4M of 2, 6-dichlorophenol indophenol. p-Chloromercuribenzoate, phenylmercuric nitrate, as well as silver and mercuric ions inhibited most of the activity. L-Sorbose, sucrose and polyols were inactive as a substrate. The partially purified enzyme preparation still has an activity toward D-glucose, D-gluconate, and several aldoses. It was proved, however, that this fructose dehydrogenase was different from either glucose or gluconate dehydrogenase. It was, therefore, proposed that the enzyme is a new type of the so-called Bertrand-Hudson enzyme.抄録全体を表示PDF形式でダウンロード (711K) -
HIROMI MITSUI, KAZUKO HARA1967 年 61 巻 5 号 p. 647-653
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーChanges induced by T2 phage infection in the deoxyribonucleoprotein of Escherichia coli was studied, and rapid decreases in the protein content and DNA-dependent RNA polymerase [EC 2. 7. 7. 6] activity in the deoxyribonucleoprotein were observed.
The activity of host DNA as a primer for RNA polymerase was not altered at least 10 minutes after the phage infection. No restoration of the reduced level of the enzyme activity was achieved by purification of the enzyme. It was suggested that immediately after phage infection, a part of RNA polymerase in the deoxyribonucleoprotein was released together with the other proteins and the liberated enzyme was rapidly inactivated by degradation.抄録全体を表示PDF形式でダウンロード (505K) -
KEITARO HIROMI, SÔZABURO ONO1967 年 61 巻 5 号 p. 654-656
発行日: 1967/05/25
公開日: 2008/11/18
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JUN-ICHI FUKUDA, EIICHI MIZUKAMI, KUNITARO IMAICHI1967 年 61 巻 5 号 p. 657-658
発行日: 1967/05/25
公開日: 2008/11/18
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YOETSU HACHISUKA, KUNIO TOCHIKUBO, YOSHIKAZU YOKOI, TAKASHI MURACHI1967 年 61 巻 5 号 p. 659-661
発行日: 1967/05/25
公開日: 2008/11/18
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KIYOMICHI HANABUSA, HISAYO KOBAYASHI1967 年 61 巻 5 号 p. 662-664
発行日: 1967/05/25
公開日: 2008/11/18
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MASAMICHI KUSUNOSE, JUNJIRO MATSUMOTO, KOSUKE ICHIHARA, EMI KUSUNOSE, ...1967 年 61 巻 5 号 p. 665-667
発行日: 1967/05/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (184K)
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