巻号一覧
70 巻, 3 号
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Tosiki NISIZAWA, Hiroshi SUZUKI, Masashi NAKAYAMA, Kazutosi NISIZAWA1971 年 70 巻 3 号 p. 375-385
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーVarious compounds such as glycerol, glucose and its derivatives, glucodisaccharides including sophorose and gentiobiose, cellooligosaccharides, cellulose, and derivatives of sophorose were shaken with washed mycelia of Trichoderma viride. Among these substances, only sophorose and gentiobiose enhanced the extracellular cellulase [EC 3. 2. 1. 4] formation by the washed mycelia, although the degree of stimulation by the latter disaccharide was approximately one seventh that of sophorose. The cellulase induction by sophorose was optimal at a concentration of 1×10-3M, and seemed to be independent of the fungal age. It was completely but in a different way inhibited by actinomycin D as well as puromycin of a suitable amount. Furthermore, various substances related to the catabolites of this fungus inhibited competitively this inductive cellulase formation. On the basis of these results, the mode of cellulase synthesis in this microorganism was discussed.抄録全体を表示PDF形式でダウンロード (705K) -
Tosiki NISIZAWA, Hiroshi SUZUKI, Kazutosi NISIZAWA1971 年 70 巻 3 号 p. 387-393
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーThe formation of cellulase [EC 3. 2. 1. 4], β-glucosidase (possibly an exo-type cellulase) [EC 3. 2. 1. 21] and xylanase [EC 3. 2. 1. 8] in washed mycelia of Trichoderma viride was markedly stimulated by sophorose. By contrast, the formation of amylase [EC 3. 2. 1. 1], acid phosphatase [EC 3. 1. 3. 2] and protease was not affected by sophorose.
Extracellular and cell-bound enzyme solutions, which were prepared from mycelial suspensions after shaking them with sophorose and L-leucine-14C and only with L-leucine-3H, were fractionated by column chromatography. The major fractions of cellulase and amylase activities from the extracellular enzyme preparations overlapped with each other, and they were chromatographed on a starch column to separate from each other. Almost all of the cellulase activity was recovered in the eluates, and seemed to be labelled only with 14C-radioactivity, while amylase was labelled with both 14C and 3H. The formation of the cell-bound cellulase was similarly affected by sophorose.抄録全体を表示PDF形式でダウンロード (404K) -
IV. Dietary Control of Some Liver Enzymes Unique to Amino Acid Metabolism and Gluconeogenesis and Its Dependence on Pancreatic HormonesHisako MATSUTAKA, Katsuyuki NAKAJIMA, Eiji ISHIKAWA1971 年 70 巻 3 号 p. 395-405
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーThe adaptability of rat liver enzymes involved in amino acid catabolism and gluco-neogensis was examined in response to feeding glucogenic substrates. Feeding of lactate and glycerol inhibited an increase in serine dehydratase [EC 4. 2. 1. 13] activity caused by starvation. Phosphoenolpyruvate carboxykinase [EC 4. 1. 1. 32] and tyrosine transaminase [EC 2. 6. 1. 5] activities remained low on feeding glycerol but not lactate. Feeding of glucogenic amino acids did not differentially depress the enzyme activities tested. Serine dehydratase activity was markedly enhanced by feeding alanine rather than lowered. Thus the effects of glucogenic substrates on enzymes catalyzing amino acid degradation and gluconeogenesis are partly differential but not strictly.
Then it was tested whether pancreatic hormones are involved in enzyme regulation by nutrients. Serine dehydratase was not induced by amino acid-feeding in pancreatectomized rats. Tyrosine transaminase could be induced by amino acid-feeding even in the absence of all of the pancreatic, adrenocortical, and hypophyseal hormones. The role of pancreas in this connection was demonstrated by pancre-atectomy of hypophysectomized rats to be in the maintenance of the enzyme levels and stimulation of the enzyme induction by amino acid-feeding. The effects of glucagon and an amino acid mixture on tyrosine transaminase were additive in hypophysectomized-pancreatectomized rats. Phosphoenolpyruvate carboxykinase activity in pancreatectomized rats was depressed by feeding of glycerol and more consistently by combined administration of glycerol and insulin.抄録全体を表示PDF形式でダウンロード (719K) -
Susumu YASUOKA, Setsuro FUJII1971 年 70 巻 3 号 p. 407-415
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリー(1) When rat epididymal fat pads were incubated in buffer under physiological conditions at 37°C, release of lipase [EC 3. 1. 1. 3] from the tissue was only slight in the absence of heparin, but significant on addition of heparin. Release of glucose-6-phosphate dehydrogenase [EC 1. 1. 1. 49] under these conditions was not stimulated by addition of heparin.
When epididymal fat pads were incubated in unphysiological buffer such as 0.015M sodium phosphate buffer, pH 8.0, considerable lipase was released, and addition of heparin had no significant effect on the release. These results suggest that heparin specifically stimulates release of lipase in vitro, and that intact tissue is required for this stimulation.
(2) Serum is required both for optimal activity of lipase released from adipose tissue by heparin in vitro and for optimal activity of purified clearing factor lipase which appears in the blood stream following intravenous injection of heparin. The former enzyme was completely precipitated by antibody to the latter.抄録全体を表示PDF形式でダウンロード (591K) -
I. Activation of Brain Mitochondrial Phosphotransferases by Magnesium IonTsukasa SUGANO, Otoji NAGAI1971 年 70 巻 3 号 p. 417-427
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーThe mechanism of respiratory control by ADP in brain mitochondria was analyzed from both respiratory activity and interconversion of adenine nucleotides. The respiration of tightly coupled brain mitochondria was stimulated by added magnesium. The experiments performed under various metabolic conditions indicated that the stimulatory effect of added magnesium ion on state 4 respiration depended on the activation of adenylate kinase [EC 2. 7. 4. 3] and creatine kinase [EC 2. 7. 3. 2], whereas, various other factors participated in the stimulation of state 3 respiration. The influence of hexokinase [EC 2. 7. 1. 1] or ATPase [EC 3. 6. 1. 3] on the stimulation of the state 4 respiration by added magnesium was not observed in the experimental condition studied. These results indicate that, in brain mitochondria, the reactions catalyzed by adenylate kinase and creatine kinase act as a secondary mechanism of respiratory control, and that the reaction catalyzed by creatine kinase competes with the oxidative phosphorylation system for ADP.抄録全体を表示PDF形式でダウンロード (661K) -
Hidehiko NAKANO, Katsuyuki SASAKI, Yasuhiro KUROKAWA, Hirohiko KATSUKI1971 年 70 巻 3 号 p. 429-440
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリー1. A bacterium which grows in a medium containing β-methylmalic acid as a sole carbon source was isolated from soil, and the metabolism of β-methylmalic acid by this bacterium was investigated.
2. β-Methylmalic acid was metabolized without adaptation and was converted to α-ketobutyric acid by the resting cells grown in a complex medium.
3. Cell-free extracts of this bacterium contained an enzyme which catalyzes the conversion of β-methylmalic acid to α-ketobutyric acid. This enzyme was partially purified and some of its properties were investigated. The results of DEAE-Sephadex column chromatography and gel electrophoresis supported the view that this enzyme activity is due to broad substrate specificity of β-isopropylmalate dehydrogenase, a member of the enzyme system for leucine biosynthesis.抄録全体を表示PDF形式でダウンロード (1530K) -
Katsuyuki SASAKI, Hidehiko NAKANO, Hirohiko KATSUKI1971 年 70 巻 3 号 p. 441-449
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーA cell-free extract of a Bacillus which can grow on β-methylmalate (MMA)** as a sole carbon source was found to convert MMA into citramalate (CMA) via citraconate (CCA). The optical rotation of CMA formed from CCA was levorotatory and MMA formed from CCA was inferred to have erythro configuration from its behavior on gas chromatography. This form of MMA was oxidized to α-ketobutyrate (KBA) by the extract in the presence of NAD+, K+, and Mg2+. The enzyme which catalyzes the isomerization of MMA to CMA via CCA is similar to dimethylcitraconase involved in leucine biosynthesis in the mode of reaction, non-requirement of cofactor, and in the sensitivity to sulfhydryl reagents such as 2-mercaptoethanol and cysteine. The activities of CCA hydratase concerned in the isomerization and of dimethylcitraconase were not separated from each other by Sephadex G-100 and DEAE-Sephadex column chromatography. These results suggest that dimethylcitraconase has a broad substrate specificity and acts methyl- as well as isopropyl- and ethylmalic acids.
The significance of the metabolism of MMA as reported here was discussed from a viewpoint of the utilization of MMA as an energy source by the cells.抄録全体を表示PDF形式でダウンロード (568K) -
Masamichi TAKAGI, Tadashi INOUE, Yasukiyo UMEMURA1971 年 70 巻 3 号 p. 451-455
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーRNA was extracted fro n polysomes of rat liver by SDS-phenol method in the presence of bentonite and analyzed by polyacrylamide gel electrophoresis. When the gel concentration of 3.1% was used, four minor peaks were detected between the peaks of 28S and ISIS RNA's. These RNA's were obtained from both free and membrane-bound polysomes. They were found to be associated with 60S ribosomal subunits. Upon treatment of polysomes with a low concentration of pancreatic RNase [EC 2. 7. 7. 16], no degradation of these RNA's was observed. These results suggest that they are not messenger-type RNA's but structural RNA's in larger ribosomal subunits. The possible origin of these RNA's is discussed.抄録全体を表示PDF形式でダウンロード (314K) -
Morimitsu NISHIKIMI, Mayumi OSAMURA, Kunio YAGI1971 年 70 巻 3 号 p. 457-465
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーKinetic studies on the interaction of D-amino acid oxidase [D-amino acid:O2 oxidoreductase (deaminating), EC 1. 4. 3. 3] with inhibitors, benzoate and o-aninobenzoate, which are considered to be substrate-substitutes of this enzyme, were performed by using a stopped-flow spectrophotometric technique at pH 8.2 and 15°C. The time course of the spectral change upon mixing the enzyme with either of the inhibitors is biphasic. The rapid change, which amounts to 93% of the total change, is followed by a slow small one, which indicates the unhomogeneity of the uncomplexed enzyme. The application of the relaxation method to the rapid phase of the reaction revealed the two-step mechanism for the enzyme-inhibitor binding as follows,
E+I_??_(EI)1_??_(EI)2
where the first step, E+I_??_(EI)1, is much faster than the second step, (EI)1_??_(EI)2, the spectral change occurring in the latter step.抄録全体を表示PDF形式でダウンロード (1309K) -
VI. Hydrolysis of p-Nitrophenyl Acetate by an Interaction between Sulfhydryl and Carboxyl Groups in Copoly (L-Cys, L-Glu)Takashi KOMAI, Junzo NOGUCHI1971 年 70 巻 3 号 p. 467-476
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーThe hydrolysis of p-nitrophenyl acetate (NPA) was catalyzed by copoly (L-Cys, L-Glu 1:1). The pH-activity curve was bell-shaped with two optima of pH 6.1 at 40°C and pH 7.1 at 40°C, unlike with other copolymers which gave one peak as shown previously. The catalytic action of copoly (L-Cys, L-Glu 1:1) was compared with that of a mixture of poly-L-Glu and poly-L-Cys with components in the same proportions as in the copolymer. The activity of the copolymer at pH 6.1 (40°C) was about 20 fold higher than that of poly-L-Glu at the optimum pH of 5.2. At pH 7.1 (40°C), the activity was 1.5 fold higher than that of poly-L-Cys at the optimum pH of 7.8. The mechanisms of catalytic hydrolysis at the two optima seem to be different; the former seems to involve cooperation between SH and COO-, and the latter bifunctional catalysis between SH and OH-.
Copoly (L-Cys, L-Asp) and sequential poly-L-cysteinyl-L-glutamic acid had no activity. A method was devised for preparation of a sample solution of cysteinyl copolymer free from activator for measurement of NPA hydrolysis.抄録全体を表示PDF形式でダウンロード (691K) -
XIII. Isolation and Amino Acid Sequences of Tryptic Peptides from Performic Acid-oxidized Ribonuclease T1Kenji TAKAHASHI1971 年 70 巻 3 号 p. 477-495
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーPerformic acid-oxidized ribonuclease T1 [EC 2. 7. 7. 26] was hydrolyzed by trypsin and the resulting peptides were fractionated by high voltage paper electrophoresis or by column chromatography on Dowex 1. Upon paper electrophoresis peptides were separated into five major plus some minor fractions. One major peptide fraction contained two acid-insoluble core peptides, which were separated from each other by subsequent chromatography on DEAE-cellulose. The other four major and one minor fractions were found to represent individual peptides. Quantitative analyses for amino acid composition, end groups and partial amino acid sequence have been carried out with each peptide. These analytical results indicated that in addition to the ex-pected cleavages at one lysine and one arginine residue, cleavages also occurred predominantly at the peptide bonds involving the carboxyl groups of two tyrosine residues. The results permitted deduction of a most probable alignment of these peptides, which almost fully accounts for the amino acid composition of the original protein:
H-Ala-CySO3H-Asx-Tyr-Thr-(CySO3H2, Asx1, Ser1, Gly1, Tyr0-1)-Ser-Ser-Ser-Asp-Val-Ser-Thr-Ala-((GluNH2)1, Gly1, Ala2)-Tyr-GluNH2-(Asx2, Thr1, Ser1, Glx2, Gly2, Val1, Leu1, His1)-Ser-Tyr-Pro-His-Lys-Tyr-Asx-(Asx3, Ser4-5, Glx2, Pro2, Gly2, Val1, Ile1, Leu1, Tyr2-3, Phe2, (O-Trp)1)-Val-Tyr-Ser-Gly-Pro-Gly-Ser-Gly-Ala-Asp-Arg-Val-Val-(Asx3, Thr0-1, Glx2, Gly1, Ala1, Val1, Ile1, Leu1, Phe1, His1)-Thr-(CySO3H1, Asx2, Ser1, Glx1, Gly2, Ala1, Val1, Phe1)-Thr-OH.
Fig. 6. A partial structural formula for oxidized ribonuclease T1. The major tryptic peptides obtained from the oxidized protein and some of their fragments produced by further enzymatic hydrolyses are aligned in the most probable way. The sequences of the amino acid residues in parentheses are undetermined * Established to be the true value in the subsequent studies (3, 4).抄録全体を表示PDF形式でダウンロード (1271K) -
Noriko SHIMAKI, Kiyoshi IKEDA, Kozo HAMAGUCHI1971 年 70 巻 3 号 p. 497-508
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーThe effects of urea and guanidine hydrochloride (GuHCl) on the circular dichroism (CD) and ultraviolet absorption spectrum of hen egg-white lysozyme [EC 3.2.1.17] were studied. Urea and GuHCl enhanced the aromatic CD bands of lysozyme in a nondenaturing concentration range. By analyzing the increase in the CD bands with increasing concentration of urea or GuHCl, it was found that one mole of urea or GuHCl interacts with one mole of lysozyme. The difference absorption spectra of lysozyme produced by urea were also interpreted in terms of urea-lysozyme interaction. On the basis of these facts, the tryptophyl exposure of the lysozyme mole-cule was discussed.抄録全体を表示PDF形式でダウンロード (634K) -
Yutaka MAEDA, Yuhei MORITA, Chiaki YOSHIDA1971 年 70 巻 3 号 p. 509-514
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーThe Mössbauer spectra of frozen solutions of horse heart metmyoglobin, containing 57Fe-enriched protohematin, were measured at 243, 195, 77 and 4.2°K. At 195°K or higher temperatures a pair of broad absorption lines was observed, while at lower temperatures hyperfine lines appeared. The result showed that the heme-iron in metmyoglobin is in the ferric high-spin state. The Mössbauer spectra of metmyo-globin-hydrogen peroxide compound were also measured. The spectra exhibited a pair of sharp absorption lines in a wide range of temperatures from 4.2°K to 195°K. The Mössbauer parameters of the compound were compatible to the quadrivalent of the heme-iron in the compound.抄録全体を表示PDF形式でダウンロード (377K) -
Shizuo WATANABE, Stephen L. GAFFIN1971 年 70 巻 3 号 p. 515-527
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーIt has been known that calcium (in the presence of magnesium and ATP) can exert two different effects on the myosin B-superprecipitation. High concentrations of calcium inhibit superprecipitation by reducing the concentration of MgATP complex (a first effect), whereas low concentrations of calcium activate it by inactivating relaxing protein (a second effect). We have now found that high concentrations of calcium can inhibit superprecipitation only in acidic pH and activate it in alkali pH a third effect of calcium). Characteristics of the superprecipitation activated by the third effect of calcium are (a) that the pH versus rate plot gives a first order sigmoidal curve with an optimum at alkali pH, and (b) that the required concentration of calcium is much higher than that of ATP. Kinetic analysis suggests that CaATP complex and free calcium are both required for the third effect of calcium. High concentrations of manganese (with ATP) are also found to activate superprecipitation in alkali pH. Studying the pH dependence, the ATP requirement and the manganese- or calcium-requirement, we find the activation effect of high concentrations of manganese or calciumn on the myosin B-superprecipitation to be very similar to their activation effect on the myosin A-ATPase. We therefore conclude that the third effect of calcium involves direct interactions of free calcium and CaATP complex with myosin A.抄録全体を表示PDF形式でダウンロード (874K) -
Takeyori SAHEKI, Takae TOWATARI, Nobuhiko KATUNUMA1971 年 70 巻 3 号 p. 529-531
発行日: 1971/09/25
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) -
Kenji MURAKAMI, Katashi MAKINO1971 年 70 巻 3 号 p. 533-535
発行日: 1971/09/25
公開日: 2008/11/18
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Ayako MATSUSHIMA, Keiji NAKAMURA, Kazuo SHIBATA, Yuji INADA1971 年 70 巻 3 号 p. 537-539
発行日: 1971/09/25
公開日: 2008/11/18
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Kinji TSUKADA, Arasuke NISHI1971 年 70 巻 3 号 p. 541-542
発行日: 1971/09/25
公開日: 2008/11/18
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Hiroaki HAYASHI, Koichi IWAI1971 年 70 巻 3 号 p. 543-547
発行日: 1971/09/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (311K)
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