巻号一覧
78 巻, 5 号
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Hiroshi NAKADA, Ikuo FUNAKOSHI, Ikuo YAMASHINA1975 年 78 巻 5 号 p. 863-872
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーPlasma membranes were isolated from an ascites hepatoma, AH 130, by the fluorescein mercuric acetate (FMA) method. Glycopeptides and mucopolysaccharides were prepared by digesting the membranes with pronase, then by fractionating the digest chromatographically and electrophoretically. Isolated fractions were analyzed for their amino acid and carbohydrate compositions. Results were compared with those for corresponding fractions from AH 66 (J. Biochem. 76, 319-333 (1974)).
Mucopolysaccharides and a series of glycopeptides were isolated from the fraction excluded from Sephadex G-50. The mucopolysaccharides were identified as a family of heparan sulfates with different electrophoretic mobilities. The glycopeptides contained serine, threonine, galactose, galactosamine, glucosamine, and sialic acid as the major constituents and aspartic acid and mannose as minor ones. This suggests that most of the carbohydrate moieties are linked to serine or threonine (O-glycosidic), and that some are linked to asparagine (N-glycosidic). No nearly purely O-glycosidic glycopeptides were found in this fraction from AH 130, though they were the major glycopeptides from the AH 66 plasma membranes.
In the fraction included in the gel, glycopeptides containing fucose, galactose, mannose, glucosamine, galactosamine, and sialic acid were found. The presence of galactosamine suggests that some of the glycopeptides are O-glycosidic though most are N-glycosidic. In the corresponding fraction from AH 66, nearly purely N-glycosidic glycopeptides were found.抄録全体を表示PDF形式でダウンロード (2752K) -
Masahiko ENDO, Zensaku YOSIZAWA1975 年 78 巻 5 号 p. 873-878
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーCrude glycoproteins were extracted with 0.15 M NaCl from the pooled endometnal scrapings of rabbit uteri after treatment with estrogen. The crude glycoproteins were fractionated with ammonium sulfate, followed by DEAE-cellulose column chromatography, treatment with CM-Sephadex C-25 and gel filtration on Sephadex G-200, Subsequently, purification of an acidic glycoprotein was carried out by gel filtration on Sephadex G-200 and then Sepharose 4B. The results of electrophoresis and enzymatic digestion, together with analytical data and the infrared spectrum indicated that the acidic glycoprotein was a sulfated glycoprotein.抄録全体を表示PDF形式でダウンロード (445K) -
Shigeyuki EBISU, Keijiro KATO, Shozo KOTANI, Akira MISAKI1975 年 78 巻 5 号 p. 879-887
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーD-Fructans synthesized from sucrose by cell-free systems of strains of Streptococcus mutans and Strep. salivarius have been shown by methylation and enzymatic studies to have different glycosidic linkages. The cold water-insoluble D-fructans from Strep.mutans strain BHT and JC-1 have inulin-type structures consisting β-(2→l)-D-fructo-furanosidic linkages, with average repeating units of 8 and 27 sugar residues, respectively, whereas the water-soluble fructan from Strep. salivarius strain HHT has a levan-type branched structure consisting β-(2→6)-D-fructofuranosidic linkages with an average repeating unit of 9 sugar residues. The solubility properties of these fructants are discussed on the basis of the structural differences.抄録全体を表示PDF形式でダウンロード (659K) -
Kimio UMEKI, Takehiko YAMAMOTO1975 年 78 巻 5 号 p. 889-896
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリー1. A singly branched heptaose produced as a limit dextrin in the digest of β-limit dextrin with liquefying α-amylase [EC 3. 2. 1. 1] of Bacillus amyloliquefaciens was isolated in a paper chromatographically pure state.
2. Analysis using several enzymes revealed that the isolated branched dextrin was a mixture of six singly branched heptaoses with different ramifying points.
3. All the branched heptaoses contained a 62-α-maltosylmaltotriose moiety in their molecules, differing only in the mode of attachment of one maltose or two glucose residues by α-1, 4-glucosidic bonds from this core dextrin.
4. The formation of various singly branched heptaoses (the present paper) and hexaoses (the previous paper) is discussed regarding the attack site specificity of the enzyme on β-limit dextrin.抄録全体を表示PDF形式でダウンロード (3455K) -
Kimio UMEKI, Takehiko YAMAMOTO1975 年 78 巻 5 号 p. 897-903
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーFrom the digest of β-limit dextrin (prepared from glutinous rice starch) with saccharifying α-amylase of Bacillus subtilis [EC 3.2.1.1] (BSA), two extensively branched dextrins consisting of nine (No. 6, 1 Fig. 1) and ten (No. 7, Fig. 1) glucose units were isolated by paper chromatography
Structural analysis using various enzymes revealed that No. 6 and No. 7 were both mixtures of four triply branched dextrins. They had structures which were built up with 63-α-glucosylmaltotriose and/or 62-α-glucosylmaltose as a linking unit. However, the branching configuration and the minimum α-1, 4-glucosidic linkages existing between two branches followed one of the three structures shown below:
1) _??_, 2) _??_, and 3) _??_. 2抄録全体を表示PDF形式でダウンロード (2124K) -
Daisaburo FUJIMOTO1975 年 78 巻 5 号 p. 905-909
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーThe collagen from the cuticle of Ascaris lumbricoides was digested by Clostridium histolyticum collagenase [EC 3. 4. 24. 3] in the presence and absence of CaCl2. About 1.2 μmoles of amino groups per mg collagen was liberated when the digestion was performed in the presence of 5mM CaCl2, whereas about 0.5 μmole of amino groups per mg collagen was liberated by digestion in the absence of CaCl2. In contrast, CaCl2 influenced the extent of hydrolysis of rat tail tendon colagen only slightly. The results suggest that CaCl2 is necessary for the hydrolysis of certain regions in the molecule of Ascaris collagen and that such structures may not be present in mammalian collagens.抄録全体を表示PDF形式でダウンロード (306K) -
Atsushi TAKEDA, Akira HACHIMORI, Katsumi SATO, Tatsuya SAMEJIMA1975 年 78 巻 5 号 p. 911-924
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーNative bovine liver catalase [EC 1. 11. 1. 6] and catalase acetylated with N-acetylim-idazole (AI) both combined with sodium dodecyl sulfate (SDS) to form catalase-SDS complexes. The differences between native and acetylated catalase bound to SDS were investigated as regards enzymatic activity, absorption spectra, ORD and CD, sedimentation velocity and fluorescence spectra. It was found that the binding of SDS with both catalases depended on incubation time and SDS concentration, and that the acetylation of catalase had some protective effect on the denaturation of the molecule by SDS, which may be ascribed to a reduction of ionic interaction between SDS and the protein on acetylation. The native catalase was found to split into three smaller components on incubation with 1% SDS for 96hr, whereas the acetylated catalase split into two smaller components. These smaller components were isolated by gel nitration through Sephadex G-100. The isolated components had estimated molecular weights of 60, 000, 30, 000, and 10, 000-12, 000 on the basis of SDS-polyacrylamide gel electrophoresis as well as gel filtration. The second component was not detected in the case of the acetylated catalase. The last component was the smallest which has ever been isolated from split molecules of catalase. Measurements of absorption spectra, ORD and CD as well as amino acid composition of some isolated components were carried out in this study.抄録全体を表示PDF形式でダウンロード (1128K) -
Masaaki MOROI, Makoto YAMASAKI, Nobuo AOKI1975 年 78 巻 5 号 p. 925-928
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーUnlike in the reaction of anhydrotrypsin and soybean trypsin inhibitor, human α1-antitrypsin was found not to form a complex with bovine anhydrotrypsin. This was shown using three different methods: electrophoresis, affinity chromatography on an anhydrotrypsin-coupled Sepharose column and equilibrium competitive binding assay.These results indicate the importance of the active site serine of trypsin in formation of a complex with α1-antitrypsin.抄録全体を表示PDF形式でダウンロード (290K) -
Susumu KURIOKA, Fumihide INOUE, Makoto MATSUDA1975 年 78 巻 5 号 p. 929-934
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーCarboxyl groups of native human fibrinogen were modified with glycine methyl ester and l-ethyl-3 (3-dimethylaminopropyl) carbodiimide. It seemed likely that the modification occurred stepwise. Approximately 26% of the carboxyl groups of fibrinogen was modified finally. The modified fibrinogen had no interaction with cationic detergent, and did not form any complex with the detergent. In dilute acid, fibrinogen was observed to show only a slight interaction with cationic detergent. It is probable that the exposed and ionized carboxyl groups are essential for the formation of a complex between fibrinogen and cationic detergent.抄録全体を表示PDF形式でダウンロード (2183K) -
Chiaki YOSHIDA, Mitsuyoshi YOSHIKAWA1975 年 78 巻 5 号 p. 935-945
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーTwo proteinase inhibitors, designated as inhibitors I and II, were purified from adzuki beans (Phaseolus angularis) by chromatographies on DEAE- and CM-cellulose, and gel filtration on a Sephadex G-100 column. Each inhibitor shows unique inhibitory activities. Inhibitor I was a powerful inhibitor of trypsin [EC 3. 4. 21. 4], but essentially not of chyrnotrypsin [EC 3. 4. 21. 1]. On the other hand, inhibitor II inhibited chymotrypsin more strongly than trypsin. The molecular weights estimated from the enzyme inhibition were 3, 750 and 9, 700 for inhibitors I and II, respectively, assuming that the inhibitions were stoichiometric and in 1:1 molar ratio. The amino acid compositions of both inhibitors closely resemble those of low molecular weight inhibitors of other leguminous seeds: they contain large amounts of half-cystine, aspartic acid and serine, and little or no hydrophobic and aromatic amino acids. Inhibitor I lacks both tyrosine and tryptophan residues. The molecular weights were calculated to be 7, 894 and 8, 620 for inhibitors I and II, respectively. The reliability of these molecular weights was confirmed by the sedimentation equilibrium and 6M guanidine gel filtration methods. On comparison with the values obtained from enzyme inhibition, it was concluded that inhibitor I had two trypsin inhibitory sites on the molecule, whereas inhibitor II had one chyrnotrypsin and one trypsin inhibitory sites on the molecule.抄録全体を表示PDF形式でダウンロード (1489K) -
Akemi SUZUKI, Ineo ISHIZUKA, Tamio YAMAKAWA1975 年 78 巻 5 号 p. 947-954
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーA ganglioside containing fucose (fucoganglioside) was obtained from boar testis and purified by silicic acid and DEAE-cellulose column chromatographies and preparative thin layer chromatography. The structure of this ganglioside, determined by chemical and enzymatic methods was:
Fucα(l-2)Gal(l-3)GalNAc(l-4)Gal(l-4)Glc-Ceramide
Its fatty acids were mainly long chain saturated ones (20:0, 22:0, 24:0). Its long chain bases consisted of 27% C16:1 sphingosine and 68% C18:1 sphingosine.抄録全体を表示PDF形式でダウンロード (2100K) -
Takayasu DATE, Koichi SUZUKI, Kazutomo IMAHORI1975 年 78 巻 5 号 p. 955-967
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーTwo types of RNA polymerases [EC 2. 7. 7. 6], polymerases A and B, exist in thermophilic bacteria, Thermus thermophilus HB8. Polymerase B is apparently like the core enzyme of polymerase A but is active only when an alternating copolymer of deoxyadenylic and deoxythymidylic acids (poly d(A-T)) or a mixture of homopolymers of deoxyadenylic acid and deoxythymidylic acid (poly dAdT) is used as a template. Polymerase B was further characterized to elucidate its relation to polymerase A and to determine why it is inactive on natural DNA's.
1. Polymerase B did not show pyrophosphate exchange activity. Dinucleoside monophosphates did not activate the RNA-synthesizing activity. The results suggested that polymerase B had no initiation and presumably no elongation activities.
2. Polymerase B had about 6 times greater affinity to DNA than polymerase A. The binding of polymerase B to DNA was, however, reversible. The complex of DNA with polymerase A was stable and the polymerase was not removed from the initial complex even when a large amount of DNA was added.
3. E. coli σ subunit could not stimulate the activity of polymerase B toward DNA's.
4. Polymerase B could utilize poly d(A-T) and poly dAdT as templates, but could not use Bacillus cereus DNA, though the structure is reported to be similar to that of poly d(A-T).抄録全体を表示PDF形式でダウンロード (967K) -
I. Immunochemical Assay of Catalase in Liver Cell FractionsFumiko KAWAMATA, Toshiharu SAKURAI, Tokuhiko HIGASHI1975 年 78 巻 5 号 p. 969-974
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーRats were injected twice intraperitoneally with 20mg of allylisopropylacetylcarbamide (Sedormid) per 100g of body weight at an interval of 12hr. The level of catalase [EC 1. 11. 1. 6] in various liver cell fractions was determined both enzymatically and immunochemically 12 hr after the second injection.
1. The decrease in catalase protein assayed by the immunochemical method directly confirmed the inhibition of biosynthesis of the enzyme by this porphyrinogenic drug.
2. The occurrence of a considerable amount of catalase protein with no enzymatic activity was demonstrated both in the peroxisomes and in the supernatant fraction.
3. The amount of catalase-synthesizing polysomes in hepatic cell was reduced in Sedormid-treated rats by the extent comparable to the decrease in the concentration of liver catalase.抄録全体を表示PDF形式でダウンロード (477K) -
II. Double-labeling of Catalase with [14C] Leucine and δ-[3H] Aminolevulinic AcidFumiko KAWAMATA, Toshiharu SAKURAI, Tokuhiko HIGASHI1975 年 78 巻 5 号 p. 975-980
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーDouble-labeling of liver catalase [EC 1. 11. 1. 6] with [14C] leucine and δ-[3H] arninolevulinic acid was carried out both in vivo and in vitro using rats treated with allylisopropylacetylcarbamide (Sedormid). These radioactive precursors were incorporated into catalase at a lower rate than in normal rats. In particular, the incorporation of 3H was remarkably inhibited. The results suggest that the administration of Sedormid can inhibit synthesis of the protein moiety of catalase, and possibly interfere with the binding of heme to the catalase protein.抄録全体を表示PDF形式でダウンロード (386K) -
Kazuei IGARASHI, Yasuhiro WATANABE, Chieko NAGAYAMA, Seiyu HIROSE1975 年 78 巻 5 号 p. 981-987
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーThe effect of alcohols (methanol, ethanol, and propanol) on polypeptide chain elongation was studied. In the E. coli and rat liver cell-free systems, the optimal concentration of Mg2+ decreased with increase of ethanol concentration, although the maximum polyphenylalaniiie synthesis decreased. Methanol had almost the same effect as ethanol. Propanol decreased the optimal magnesium concentration, but polyphenylalanine synthetic activity was markedly decreased. The shift of optimal Mg2+ concentration by ethanol was also observed in polylysine and polysome-dependent polypeptide syntheses. Even in the presence of spermidine, ethanol caused the shift of optimal Mg2+ concentration. Ribosome-bound Mg2+ was decreased by the addition of ethanol.
A study of the effect of alcohols on aminoacyl-tRNA formation with ten amino acids in the absence of added Mg2+ showed that the formation of arginyl-, leucyl-, and valyl-tRNA was stimulated by the alcohols. Valyl-tRNA formation in the presence of alcohols was completely inhibited by EDTA, while that in the presence of Mg2+ was inhibited slightly by EDTA. No PPi-ATP exchange was observed when alcohol was used as the only stimulant of valyl-tRNA formation.抄録全体を表示PDF形式でダウンロード (478K) -
Characterization and Mechanisms of Inhibition by Silver IonsHaruhiro HIGASHIDA, Ritsuko K. SEMBA, Fujiko NIWA, Shigeo KASHIWAMATA1975 年 78 巻 5 号 p. 989-999
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーAttempts were made to characterize mitochondrial malate dehydrogenase [L-malate: NAD+ oxidoreductase, EC 1. 1. 1. 37] (M-MDH) purified from bovine cerebrum and to elucidate the mechanisms responsible for inhibition of the enzymic activity by Ag+. The molecular weights of the native enzyme and its subunits were 54, 000-55, 000 and 30, 000-32, 000, respectively. In general, the physicochemical and catalytic properties of bovine cerebral M-MDH was not very different from those of other corresponding mammalian enzymes. Incubation of the enzyme with Ag+ caused the loss of equivalent amounts of sulfhydryls with a parallel decrease of the enzymic activity. When the enzyme was exposed to 2-, 3.5-, and 5-fold molar excesses of Ag+, the enzymic activity showed an initial rapid fall and a subsequent slow restoration to a partially inactivated level (60-70, 45-50, and 15-20% of an untreated control, respectively), while the α-helical content of the enzyme fell exponentially with time. A 7-fold molar excess of Ag+ reduced both the enzymic activity and the α-helical content to a much greater degree and no restoration of the enzymic activity was observed. The Km values of Ag+-inactivated enzyme for NADH and oxaloacetate were the same as those of the native enzyme. The data suggest that Ag+ could inhibit the enzymic activity both by reducing the structural regularity of the enzyme molecule and by attacking sulfhydryl groups necessary for the catalytic activity of bovine cerebral M-MDH.抄録全体を表示PDF形式でダウンロード (1662K) -
Yoshiaki YANO, Masachika IRIE1975 年 78 巻 5 号 p. 1001-1011
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーThe renaturation of yeast inorganic pyrophosphatase [EC 3. 6. 1. 1] (PPiase) denatured in guanidine-HCl and urea was studied. The molecular weight of PPiase was estimated to be ca. 63, 000-70, 000 by means of Sephadex G-75 column chromatography in 8M urea and 6M guanidine-HCl and by electrophoresis on polyacrylamide gel containing 8M urea. The activities of PPiase denatured in various concentrations of denaturants were measured in the presence and absence of the denaturants. In the presence of the denaturants, enzymatic activity decreased as the denaturant concentration increased up to 1.5M guanidine-HCl and 4M urea. The activities of PPiase denatured in these denaturants were not restored by dilution with buffer. However, the enzymatic activities of PPiase denatured at concentrations higher than 1.5M guanidine-HCl and 4M urea were restored by dilution with Tris-HCl buffer (pH 7.5). The recovery of the enzymatic activities of PPiase denatured in 3 to 6M guanidine-HCl and 6 to 8M urea was to a level of about 90% of the native enzyme. Irreversible denaturation of PPiase in lower denaturant concentrations was prevented in the presence of sulfhydryl reagents, dithiothreitol, glutathione, and 2-mercaptoethanol. In irreversibly denatured PPiase, the amount of free SH groups decreased markedly. These results indicated that in lower denaturant concentrations, SH groups in PPiase are very oxidizable and their oxidation may cause irreversible denaturation. In higher denaturant concentrations, where PPiase was denatured
completely, the SH groups became less reactive. The conformations of renatured PPiases were investigated by means of N-bromosuccinimide oxidation, fluorescence emission spectra and circular dichroism spectra. The PPiase denatured in 6M guanidine-HCl showed fully restored native conformation, as checked by these methods, although renatured PPiase gave a trough in the 280nm region of slightly less magnitude than that of PPiase. On the other hand, PPiase denatured in 8M urea showed restored enzymatic activity, but restoration of its conformation was incomplete as compared to PPiase denatured in 6M guanidine-HCl. PPiase renatured from material denatured in lower denaturant concentrations, such as 4M urea and 1.5M guanidine-HCl, had quite a different conformation from the native enzyme as judged from CD spectra, N-bromosuccinimide oxidation and fluorescence spectra. Differences in PPiases denatured in urea and guanidine-HCl were discussed in connection with the possible modification of amino groups in PPiase by cyanate ions.抄録全体を表示PDF形式でダウンロード (1562K) -
Preparation of a Concanavalin A Derivative with Reduced ValenceMasatoshi BEPPU, Tadao TERAO, Toshiaki OSAWA1975 年 78 巻 5 号 p. 1013-1019
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーConcanavalin A (Con A) was labeled with p-azidophenyl α-D-mannopyranoside under ultraviolet irradiation and the reaction products were separated by affinity chromatography on Sephadex G-100 at pH 5. One of the Con A derivatives thus obtained was characterized as a monovalent dimer at pH 5 and a divalent tetramer at pH 7 by sedimentation equilibrium and equilibrium dialysis, indicating that this photoaffinity labeling did not alter the quaternary structure of Con A. In agreement with these results, the labeled Con A did not show the capacity to precipitate glycogen at pH 5, but it formed precipitates with glycogen at pH 7. Although its hemagglutinating activity was found to be weaker than that of the native Con A, the dose-response curve of the labeled Con A in the mitogenic stimulation of human peripheral
lymphocytes was almost identical to that of the native Con A.抄録全体を表示PDF形式でダウンロード (539K) -
Toshihisa KUWAJIMA, Hiroshi KAGAWA, Hiroshi ASAI1975 年 78 巻 5 号 p. 1021-1029
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーIt was found that the absorption spectrum of β-naphthyl triphosphate is different from that of β-naphthyl diphosphate in the range 290-335nm.
Thus, β-naphthyl triphosphate hydrolysis by heavy meromyosin can be recorded continuously as a function of time by means of a spectrophotometer. By analyzing the time course, the apparent kinetic parameters were easily and rapidly obtained. If necessary, the true kinetic parameters, including the product dissociation constants, can be estimated spectrophotometrically.
β-Naphthyl triphosphate hydrolysis was inhibited competitively by ATP. By analyzing the time course, it was, therefore, possible to estimate the kinetic parameters of ATP hydrolysis indirectly, and reasonable values were obtained.
β-Naphthyl triphosphate hydrolysis by heavy meromyosin was performed under various conditions. Unlike that of ATP, the hydrolysis of β-naphthyl triphosphate was inhibited monotonously by treatment of heavy meromyosin with p-hydroxymercuribenzoate.抄録全体を表示PDF形式でダウンロード (652K) -
Tern HAYASHI, Koscak MARUYAMA1975 年 78 巻 5 号 p. 1031-1038
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーGlycerinated fibers of rabbit psoas muscle showed no augmentation of tension development upon incubation with heavy meromyosin, irrespective of whether the fibers were of standard length, stretched, or extracted of their myosin content. The effect of heavy meromyosin was to suppress contraction. These observations are in disagreement with certain recent published reports (Oplatka et al., 1974) and do tend to support the current sliding filament theory of muscle contraction and the necessity of bipolar myosin filaments for contraction.
A possible mechanism of contraction in protein systems, including tension generation in actomyosin fibers and superprecipitation, is described emphasizing the polarity of both myosin and actin filaments.抄録全体を表示PDF形式でダウンロード (583K) -
Machiko NAKAMURA, Shun-ichi OHNISHI1975 年 78 巻 5 号 p. 1039-1045
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーThe organization of lipids in sarcoplasmic reticulum membrane was studied with a variety of stearic spin labels and a phosphatidylcholine spin label. The ESR spectra of the spin-labeled membranes consisted of two components, one due to labels in lipid bilayer structure and the other due to more immobilized labels. The relative intensity of the immobilized component increased when the lipid content of the membrane was decreased by treatment with phospholipase A [EC 3. 1. 1. 4] and subsequent washing with bovine serum albumin. Membrane containing 30% of the intact phospholipid, i.e. 0.15mg of phospholipid per mg of protein, showed a spectrum consisting only of the immobilized component (the overall splitting ranged from 58.5G to 60.5G). The immobilized component was ascribed to lipids complexed with protein. The fraction of lipids in the two different organizations was deterined from the ESR spectrum. The activity of the Ca2+-Mg2+ dependent ATPase [ATP phosphohydrolase, EC 3. 6. 1. 3] was found to increase almost linearly with the lipid bilayer content in the membrane, whereas phosphoenzyrne formation was almost independent of the bilayer content. This indicates that the bilayer structure is necessary for the ATPase to attain its full transport activity.抄録全体を表示PDF形式でダウンロード (566K) -
XVI. Theory and Evaluation of A Model for the Membrane Transport Reaction Mediated by a Single Carrier with Three Binding Sites for SubstrateShoji AWAZU, Hiroshi AMANUMA, Akinobu MORIKAWA, Yasuhiro ANRAKU1975 年 78 巻 5 号 p. 1047-1056
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーA novel model is presented for bacterial active transport reactions which show a curvilinear Eadie-Hofstee plot and negative homotropic cooperativity in the kinetics of substrate uptake. Various models of a single carrier with multi-binding sites for substrate were constructed and examined theoretically. The fit of these models with experimental data on the kinetics of branched chain amino acid transport reactions were tested by iterative computation using the non-linear least square method.
The transport model which fitted the experimental data best consisted of a single carrier with three binding sites for substrate in which one of the substrate-carrier complexes, CSS, is not active in translocating substrate across the cytoplasmic membrane. The mechanism of homeostatic regulation of the intracellular concentration of amino acids by active transport systems is discussed on the basis of this transport model.抄録全体を表示PDF形式でダウンロード (704K) -
Katsuyoshi MIHARA, Ryo SATO1975 年 78 巻 5 号 p. 1057-1073
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーNADH-cytochrome b5 reductase [EC 1. 6. 2. 2] has been solubilized with Triton X-100 and purified to homogeneity from rabbit liver microsomes. The purified enzyme is essentially free of the detergent and phospholipids and exists in aqueous media as an oligomeric aggregate of about 13S. Its monomeric molecular weight is about 33, 000 and 1mole of FAD is associated with 1mole of the monomeric unit. The enzyme catalyzes the reductions by NADH of ferricyanide and 2, 6-dichlorophenol indophenol at an activity ratio of 1:0.09. Although the intact form of cytochrome b5 is a poorer electron acceptor than its hydrophilic fragment for the purified flavoprotein, electron transfer from the reductase to the intact cytochrome can be markedly stimulated by detergents or phospholipids, which also cause profound enhancement of the NADH-cytochrome c reductase activity reconstituted from the reductase and cytochrome b5. Upon digestion with trypsin [EC 3. 4. 21. 4], the ability of the reductase to form an active NADH-cytochrome c reductase system with the intact form of cytochrome b5 and Triton X-100 is rapidly lost. This loss of the reconstitution capability can be prevented by preincubation of the reductase with phosphatidylcholine liposomes. Trypsin digestion also results in the cleavage of the reductase molecule to a protein having a molecular weight of about 25, 000 and a smaller fragment. The purified flavoprotein can bind to liver microsomes, liver mitochondria, sonicated human erythrocyte ghosts, and phosphatidylcholine liposomes. The reductase solubilized directly from liver microsomes by lysosomal digestion, however, is devoid of membrane-binding capacity. It is concluded that the intact orm of NADH-cytochrome b5 reductase is an amphipathic protein and its hydrophobic moiety, which is removable by lysosomal digestion, is responsible for the tight binding of the reductase to microsomes and for its normal functioning in the membrane.抄録全体を表示PDF形式でダウンロード (2767K) -
Hisashi MIYAZAKI, Keiko NAMBU, Masahisa HASHIMOTO1975 年 78 巻 5 号 p. 1075-1078
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーErythrocytes of human, monkey, dog, rat, mouse, guinea pig, hen, or frog were incubated with [U-14C]adenosine at a concentration of 0.23μM, a level roughly corresponding to its plasma level in mammals. Direct utilization of adenosine by phosphorylation (the kinase pathway) and indirect tilization via hypoxanthine (the hypoxanthine pathway) were analyzed from the ratio of the specific radioactivities of nucleotide and base, as described previously (1, 2). Both human and monkey cells efficiently utilized adenosine only by the kinase pathway, while rodent cells used the same route with an efficiency which varied with the species. Canine cells incorporated adenosine in extremely small amounts both by the kinase pathway and via the hypoxanthine pathway with a marked predominance of the former. Frog erythrocytes were similar to dog cells in mechanism of utilization, but the efficiency was of the same level as that of the primates. In contrast to other animals tested, the avian cells utilized twice as much adenosine via the hypoxanthine pathway as by the kinase pathway.抄録全体を表示PDF形式でダウンロード (273K) -
XIV. Enzyme Levels of Adenylysulfate Reductase, Inorganic Pyrophosphatase, Sulfite Reductase, Hydrogenase, and Adenosine Triphosphatase in Cells Grown on Sulfate, Sulfite, and ThiosulfateKunihiko KOBAYASHI, Yuko MORISAWA, Taiko ISHITUKA, Makoto ISHIMOTO1975 年 78 巻 5 号 p. 1079-1085
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーSulfate-reducing bacteria, Desulfovibrio vulgaris, strain Miyazaki, were grown on either sulfate, sulfite, or thiosulfate as the terminal electron acceptor. Better growth was observed on sulfite and less growth on thiosulfate than on sulfate. Enzyme levels of adenylylsulfate (APS) reductase [EC 1. 8. 99. 2], reductant-activated inorganic pyrophosphatase [EC 3. 6. 1. 1], sulfite reductase [EC 1. 8. 99. 1] (desulfoviridin), hydrogenase [EC 1. 12. 2. 1], and Mg2+-activated ATPase [EC 3. 6. 1. 3] were compared in crude extracts of these cells at various stages of growth.
1) The specific activity of APS reductase in sulfite-grown cells was only one-fourth that in sulfate-grown cells throughout growth. Thiosulfate-grown cells had an activity intermediate between those of sulfate- and sulfite-grown cells.
2) Cells grown on sulfite had lower specific activity of reductant-activated inorganic pyrophosphatase than cells grown on sulfate or thiosulfate.
3) The specific activity of sulfite reductase (desulfoviridin) was highest in sulfitegrown cells. The sulfite medium gave the enzyme in high yield as well as with high specific activity.
4) The specific activities of hydrogenase and Mg2+-ATPase were not significantly altered by electron acceptors in the growth medium.抄録全体を表示PDF形式でダウンロード (553K) -
Circular Dichroism and Magnetic Circular Dichroism Studies of Metmyoglobin and Its DerivativesMasao KAJIYOSHI, F. Koichi ANAN1975 年 78 巻 5 号 p. 1087-1095
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーThe circular dichroism (CD) and magnetic circular dichroism (MCD) spectra of horse heart metmyoglobin and the following derivatives were measured in the Soret and near ultraviolet regions: metmyoglobin and its peroxide compound, and hydroxide, cyanide, azide, and fluoride derivatives. The heme-related CD bands in the Soret and near ultraviolet wavelength regions were altered by ligand substitution, though their relationships to the magnetic moment were quite different. In the Soret region, the CD peak had no definite relation to the magnetic moment, while in the near ultraviolet region the magnitude of the CD peak decreased with the magnetic moment. The MCD peak in the Soret and near ultraviolet regions also varied with ligand substitution. The magnetic ellipticity decreased with the magnetic moment in both wavelength regions. There was a more quantitative correlation between the magnetic ellipticity and the magnetic moment in the near ultraviolet region than in the Soret region. Metmyoglobin peroxide compound exhibited slightly different behavior in
the MCD spectrum from other derivatives. It is suggested that the heme iron of the metmyoglobin peroxide compound is in an oxidation state other than the ferric state and that the porphyrin structure of metmyoglobin may be modified by the reaction with hydrogen peroxide.抄録全体を表示PDF形式でダウンロード (698K) -
Yoshio TAKAHASHI1975 年 78 巻 5 号 p. 1097-1100
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーRepressed respiration of Escherichia coli cells grown in the presence of 2% glucose was derepressed when the cells were incubated in a buffer containing casamino acids. The glucose-repressed cells were deficient in succinate dehydrogenase [EC 1. 3. 99. 1] and isocitrate lyase [EC 4. 1. 3. 1] activities, which increased during the incubation. The increases in respiratory activity and enzyme activity on incubation were repressed by glucose, but except for isocitrate lyase these repressions could be restored by the addition of cyclic adenosine 3', 5'-monophosphate. Inhibitors of protein synthesis blocked the increase of enzyme activity on incubation without glucose, or with glucose and the cyclic nucleotide.抄録全体を表示PDF形式でダウンロード (284K) -
Yoshiaki NONOMURA, Eisaku KATAYAMA1975 年 78 巻 5 号 p. 1101-1104
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーThe fine structure of the purified actin filament was investigated by negative staining. The actin filament polymerized in Tris-HCl buffer and KC1 showed a collapsed image different from that of a double stranded helix. Addition of ATP, ADP, or inorganic orthophosphate, however, converted it into a straight filament with typical double strands.抄録全体を表示PDF形式でダウンロード (2160K) -
Susumu ITO, Taro NAKAMURA, Yoshitomo EGUCHI1975 年 78 巻 5 号 p. 1105-1107
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーHighly purified methioninase from Pseudomonas putida, which catalyzes α, γ-elimination reactions of homocysteine and its S-substituted derivatives as well as α, β-elimination reactions of cysteine and its derivatives, was found to catalyze exchange reactions between the substituent at the γ-carbon of homocysteine substrates and exogenously added alkanethiols, forming the corresponding S-alkylhomocysteines. It also catalyzed similar β-exchange reactions between cysteine and alkanethiols. Thus, all the substrates for the methioninase-catalyzed elimination reactions also appear to be available for the exchange reactions.抄録全体を表示PDF形式でダウンロード (202K) -
Ichitomo MIWA, Jun OKUDA, Hatsumi NIKI, Atsushi NIKI1975 年 78 巻 5 号 p. 1109-1111
発行日: 1975/11/25
公開日: 2008/11/18
ジャーナル フリーIsolated rat islets were incubated in media containing either the a or β anomer of D-[l-3H]glucose for 5min at 37°. The amounts of the two anomers incorporated were determined using L-[1-14C]glucose as an extracellular space marker. The incorporation of β-D-glucose was about twice that of α-D-glucose. Our previous and present results suggest that the two anomers of D-glucose each have a preferential function in pancreatic beta cells; α-D-glucose stimulates insulin secretion, and β-D-glucose is transported into the cells.抄録全体を表示PDF形式でダウンロード (234K)
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