巻号一覧
78 巻, 6 号
選択された号の論文の28件中1～28を表示しています
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Evidence for the Similarity of Key Intermediates in Contractile and Transport ATPaseAkio INOUE, Yoshihiro FUKUSHIMA, Yuji TONOMURA1975 年 78 巻 6 号 p. 1113-1121
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーThe effects of D2O on the elementary steps in the contractile and transport ATPase [EC 3. 6. 1. 3] reactions were studied, and the following results were obtained:
1. The rate of H-meromyosin ATPase in the steady state decreased in D2O to 60% of that in H2O. Deuterium oxide did not affect the size or rate of the initial burst of P1 liberation, i.e. the amount or rate of formation of the reactive myosin-phosphate-ADP complex, MADPP Moreover, neither the rate of change in the fluorescence spectrum of H-meromyosin induced by ATP (the rate of formation of the second enzyme-ATP complex, M2ATP) nor the rate constant of decomposition of MADPP into M°+ADP+Pi was affected by D20. However, the equilibrium constant of the step M2ATP_??_MADPP decreased in D20 to about 1/2 the value in H20.
2. In the case of the Na+-K+-dependent ATPase reaction, neither the rate constant of formation of the second enzyme-ATP complex, E2ATP, nor that of decomposition of a phosphorylated intermediate, EADP_??_P, was affected by D2O. However, the equilibrium constant of the step E2ATP_??_EADP_??_P decreased in D20 to about 1/2.5-1/4 of the value in H2O.
These results suggest a similarity between the modes of binding of phosphate in MADPP in the myosin ATPase reaction and in EADP_??_P in the Na+-K+-dependent ATPase reaction.抄録全体を表示PDF形式でダウンロード (619K) -
Masami TAKAHASHI, Yuji TONOMURA1975 年 78 巻 6 号 p. 1123-1133
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーStructural and functional changes in myosin of fast muscles during early post-natal development were studied to seek correlations with well-known physiological changes in the contraction rate. The findings were as follows:
1. It is known that fetal fast muscle myosin contains three kinds of light chains. It was confirmed that their molecular weights were the same as those of adult fast muscle myosin, but different from those of adult slow muscle myosin. The amount of the smallest light chain, g3, was confirmed to increase markedly during the postnatal period.
2. The ATPase [EC 3. 6. 1. 3] activity of fetal fast muscle myosin (-1 day) was found to be about 50% of that of adult myosin. The pH-activity curve of fetal myosin ATPase was confirmed to be similar to that of adult myosin.
3. The rate of formation of the reactive myosin-phosphate-ADP complex, MADPP, was found not to change during post-natal development.
4. It was found that the rate of decomposition of MADPP in the presence of F-actin increased markedly during the post-natal period, and that the rate of decomposition of the complex of fetal myosin was only 1/6 to 1/4 of that of adult myosin. The change in the actomyosin ATPase activity was found to be closely correlated with the increase in the g3 content during development.抄録全体を表示PDF形式でダウンロード (732K) -
Toshiaki HIRATSUKA1975 年 78 巻 6 号 p. 1135-1147
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリー1. From NMR, IR and visible absorption studies of 2'(or 3')-O-(2, 4, 6-trinitrophenyl)-adenosine 5'-triphosphate (TNP-ATP), 2'(or 3')-O-(2, 4, 6-trinitrophenyl) adenosine (TNP-Ad), and l-(2'-hydroxyethoxy)-2, 4, 6-trinitrobenzene (TNP-EG), it was concluded that there is an intramolecular interaction between the base and 2, 4, 6-trinitrophenyl (TNP) moieties in the TNP-ATP molecule.
2. A broad new absorption band was observed in the 530-630nm region when excess indole was added to reaction mixtures containing TNP-ATP dissolved in 50% methanol or dimethyl sulfoxide. On addition of aromatic amino acid derivatives, TNP-ATP and TNP-Ad underwent spectral shifts in the 400-550nm region. The formation of a 1:1 complex apparently occurred between TNP-ATP and aromatic amino acid derivatives, and the complex with N-acetyltryptophan was stable in 50% methanol. The difference spectrum of TNP-EG vs. TNP-ATP closely resembled that induced by the addition of N-acetyltryptophan to the TNP-ATP solution.
3. The binding of 2'(or 3')-0-(2, 4, 6-trinitrophenyl)adenosine 5'-diphosphate (TNP-ADP) to heavy meromyosin (HMM) was studied by the rapid gel equilibrium method using Sephadex G-25. A dissociation constant of 1.4 μM and a maximum binding number of 1.8 were obtained in 0.15M KC1, 10mM MgCl2, and 50mM Tris-HCl (pH 8.0) at 25°. TNP-ADP bound to the enzyme caused a characteristic spectral shift in the visible region. This spectral shift was explained in terms of an interaction between tryptophanyl residues and the adenine base of TNP-ADP bound to the enzyme. TNP-ADP quenched the tryptophanyl fluorescence, but TNP-EG and TNP-Ad did not. In the presence of 6M guanidine hydrochloride, TNP-ADP scarcely quenched the tryptophanyl fluorescence, its effect being comparable to that of TNP-Ad.抄録全体を表示PDF形式でダウンロード (912K) -
Hiroie OHNO, Tadao OHNO, Juichi AWAYA, Satoshi OMURA1975 年 78 巻 6 号 p. 1149-1152
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーCerulenin, a specific inhibitor of β-ketoacyl-(acyl carrier protein) synthetase [EC 2. 3. 1. 41] and 3-hydroxy-3-methylglutaryl-CoA synthetase [EC 4. 1. 3. 5], was studied to determine whether it inhibits 6-methylsalicylic acid synthesis, in which so-called “polyketide” formation, a condensation step similar to that in fatty acid synthesis, is involved. In fact, 100μg/ml (4.5×lO-4M) of cerulenin inhibited 60% of 6-methyl-salicylic acid synthetase activity and 68% of fatty acid synthetase activity of Penitillium urticae.抄録全体を表示PDF形式でダウンロード (237K) -
Hiroshi YANAGAWA, Fujio EGAMI1975 年 78 巻 6 号 p. 1153-1160
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリー1. The effects of lipoate and asparagusate on animal and plant enzymes of the TCA cycle and related metabolic pathways were studied.
2. Lipoate inhibited bovine liver glutamate dehydrogenase [EC 1. 4. 1. 3]. The inhibition may play a role in metabolic regulation.
3. Asparagusate inhibited lipoyl dehydrogenase [EC 1. 6. 4. 3] from asparagus and lettuce competitively with respect to lipoate. Asparagusate had practically no effects on other asparagus enzymes.
4. Asparagusate strongly inhibited lipoyl dehydrogenase, glutamate dehydrogenase, and isocitrate dehydrogenase [EC 1. 1. 1. 42] from animal sources, in competion with the corresponding substrate.
5. Asparagusate and lipoate also inhibited yeast glutamate dehydrogenase.
6. Based upon kinetic studies, the mode of these inhibitions is discussed.抄録全体を表示PDF形式でダウンロード (681K) -
Yohtalou TASHIMA, Nobuko YOSHIMURA1975 年 78 巻 6 号 p. 1161-1169
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーEDTA at a concentration of 1μM produced a threshold effect in the activation of purified rabbit liver fructose-1, 6-diphosphatase [EC 3. 1. 3. 11] in the presence of 5mM Mg2+ at pH 7.2. Without EDTA, biphasic activation curves were produced by Mg2+. A double-reciprocal plot of the data gave theKm values corresponding to the two linear regions. They were 0.19 and 0.83mM at pH 7.5, and 0.055 and 0.83mM at pH 9.1.
In the presence of 5μM EDTA a sigmoidal curve was obtained for Mg2+ activation in the range of noninhibitory Mg2+ concentrations at pH 7.2. The apparentKm value for Mg2+ was 0.15mM, and the Hill coefficient was 2.0. At pH 9.1cooperativity among the Mg2+ sites disappeared, and the apparent Km value for Mg2+ was 0.055mM. These Km values at pH 7.2 or 9.1 corresponded to the smaller of the biphasicKm values obtained without EDTA.
In the absence of EDTA, no inhibition by Mg2+ was observed in the Mg2+ concentration range below 10mM. In the presence of EDTA, the enzyme was inhibited markedly by Mg2+ at concentrations above 0.5mM at pH 7.2, and was more sensitive to inhibition at pH 9.1. The effects of pH on the Km value for Mg2+ activation and on the Mg2+ inhibitioncontributed to an apparent shift of the pH optimum for activity induced by EDTA.
Cooperative interaction amongfructose-1, 6-diphosphate sites was observed for the enzyme in the presence of EDTA. The Hill coefficient was approximately 1.8, and the apparent Km value for the substrate was 0.74μM. EDTA appears to make liverfructose-1, 6-diphosphatase very sensitive to various effectors. It is suggested that Mg2+ serves as a regulatorfor the enzyme activity.抄録全体を表示PDF形式でダウンロード (638K) -
Shoko MIYAZAWA, Takehiko SAKURAI, Mitsuo IMURA, Takashi HASHIMOTO1975 年 78 巻 6 号 p. 1171-1176
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリー1. Rats were fed on a diet containing ethyl p-chlorophenoxyisobutyrate (0.3%, w/w) for 14 days.
2. The alterations of contents of intermediates in the liver indicate that gluconeogenesis is inhibited at the reaction (s) between 3-phosphoglycerate and fructose-1, 6-diphosphate. The [NAD+]/[NADH] ratios in cytoplasm and mitochondria were increased about 3-and 4-fold, respectively. Marked increases in the contents of CoA and its thioesters were found.
3. Hepatic fatty acid synthesis increased about 3-fold. There was no evidence of inhibition of the acetyl-CoA carboxylase [EC 6. 4. 1. 2] reaction by the drug.抄録全体を表示PDF形式でダウンロード (450K) -
Toshihiro SHINKA, Kyozo OGURA, Shuichi SETO1975 年 78 巻 6 号 p. 1177-1181
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーComparative studies on the substrate specificity of geranylgeranyl pyrophosphate synthetase from Micrococcus lysodeikticus and from pumpkin seedling revealed that geranyl pyrophosphate was the most active of the natural substrates for the pumpkin enzyme, whereas it was the least active for the bacterial enzyme. A marked difference was also observed between the enzymes from these two sources as regards the reactivity of 3-methyl-2-alkenyl pyrophosphates as a function of the size of the alkyl group.抄録全体を表示PDF形式でダウンロード (356K) -
Keiichiro HIYAMA, Shigetaka OKADA1975 年 78 巻 6 号 p. 1183-1190
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (545K) -
Masahiro ARIKI, Toshio FUKUI1975 年 78 巻 6 号 p. 1191-1199
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーα-D-Glucopyranosyl fluoride was found to inhibit strongly the action of α-glucan phosphorylase b [EC 2. 4. 1. 1] from rabbit muscle, and that of the enzyme from potato tubers rather weakly. The inhibition is highly specific, being competitive with respect to glucose 1-phosphate and noncompetitive with respect to polysaccharide, during polysaccharide synthesis. In the reverse process, it is competitive with respect to Pi. These results have been explained by assuming that the inhibitor binds to the glucose 1-phosphate site of the enzyme, occupying both subsites which normally bind the glucosyl and phosphate moities of the substrate, but does not directly interact with the polysaccharide site. Based on this assumption, the dissociation constants of the enzyme-inhibitor and enzyme-polysaccharide-inhibitor complexes have been evaluated (0.43 and 0.20mM for the muscle enzyme, respectively; 24 and 23mM for the potato enzyme, respectively). Glucosyl fluoride also acts as a noncompetitive inhibitor with respect to AMP. A high concentration of AMP causes an inhibitory effect on the action of the muscle enzyme, the effect being manifested in the presence of glucosyl fluoride.抄録全体を表示PDF形式でダウンロード (629K) -
Toru TANAKA, Takao UCHIYAMA, Hideaki KOBORI, Kuniji TANAKA1975 年 78 巻 6 号 p. 1201-1206
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーEnzymic hydrolysis of di-D-fructofuranose 1, 2'; 2, 3' dianhydride with the bacteria Arthrobader ureafaciens was studied to elucidate its mechanism.
Hydrolysis of the difructose dianhydride to D-fructose, which did not occur with yeast invertase [EC 3. 2. 1. 26], was found to occur on incubation with an enzyme preparation from an autolysate of the above bacteria. However, incubation with enzyme which had been treated at 60° for 30min yielded an intermediate hydrolysis product. The product isolated was found to be inulobiose and to be hydrolyzed to D-fructose by the original enzyme, as well as by yeast invertase. It was thus shown that the hydrolysis of the difructose dianhydride to D-fructose with the crude enzyme took place not in a single step but in two separate steps at 2, 3' and 1, 2' linkages. It was not determined whether the entire process is mediated by one and the same β-fructofuranosidase or by different enzymes.抄録全体を表示PDF形式でダウンロード (471K) -
Kunio YAMATO, Shizuo HANDA, Tamio YAMAKAWA1975 年 78 巻 6 号 p. 1207-1214
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーIt is known that ABO blood group substances in human erythrocyte membranes are sphingoglycolipids, but recently several authors have reported that the glycoproteins of the erythrocyte membranes also have ABO blood group activities in addition to MN blood group activities and virus hemagglutination inhibitor activity.
We solubilized blood group A erythrocyte membranes with lithium diiodosalicylate and separated the glycoprotein fraction by phenol extraction and ethanol precipitation. This fraction was apparently not contaminated with glycolipid, but it showed weak blood group A activity. The activity of the glycoprotein of the erythrocyte membranes was one-sixth of that of the glycolipid fraction from the same amount of membranes.
The glycoprotein components were purified by Sephadex G-200 gel filtration in SDS. The main component isolated, PAS 1, still showed blood group A activity.抄録全体を表示PDF形式でダウンロード (597K) -
Hajime NAWATA, Tomoya KAMIYA1975 年 78 巻 6 号 p. 1215-1224
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーTwo forms (Peak A and Peak B) of thymidine kinase [EC 2. 7. 1. 75] from regenerating rat liver cytosol were resolved and partially purified by DEAE-cellulose chromatography. Both fractions were identical with respect to their substrate requirement, pH optima, metal requirements, and molecular weight, as judged by their sedimentation in sucrose density gradient centrifugation. Peak B differed from Peak A in heat sensitivity, inhibition by dCTP and Km for thymidine and ATP. Peak B enzyme was the only enzyme found in normal adult liver and Peak A enzyme was the form increasing predominantly in regenerating liver.抄録全体を表示PDF形式でダウンロード (833K) -
I. Basic Characterization of the Binding SystemMasamichi TAKAGI, Mahlon B. HOAGLAND1975 年 78 巻 6 号 p. 1225-1233
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーA simple reaction system was developed to examine the binding of polysomes to membranes of the endoplasmic reticulum and to investigate the fate of ribosomes and nascent chains during protein synthesis in vitro. The system consisted of Sephadex G-25 treated post-mitochondrial fraction prepared from rat liver (Sephadex-PM) as a source of membranes, and radioactive free polysomes prepared from another rat liver. The following results were obtained.
1. Nascent chains on free polysomes labeled in vivo were transferred to membranes in vitro. The process required protein synthesis.
2. This reaction occurred in two steps: a) Binding of the free polysomes to membranes in the absence of protein synthesis. b) Release of ribosomes, leaving nascent chains on the membranes, requiring protein synthesis.
3. A portion of the ribosomes found on membranes in vivo (membrane-bound ribo-somes) was also released from the membranes during incubation in vitro, leaving their nascent chains on the membranes.
The significance of the transfer of nascent chains from free polysomes to membranes in vitro is discussed in the light of known polysome-membrane interaction in vivo.抄録全体を表示PDF形式でダウンロード (722K) -
Akira HACHIMORI, Atsushi TAKEDA, Tsuneyuki NAGAOKA, Harumi SUZUKI, Yos ...1975 年 78 巻 6 号 p. 1235-1240
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーThe SH groups of glutamine synthetase [EC 6. 3. 1. 2] from Bacillus stearothermophilus were modified with 5, 5'-dithiobis (2-nitrobenzoic acid) in order to determine the number of SH groups in the molecule as well as the effect of the modification on the enzyme activity. Three SH groups per subunit were detected after complete denaturation of the enzyme with 6M urea, one of which was essential for the enzyme activity in view of its reactivity with 5, 5'-dithiobis (2-nitrobenzoic acid) on addition of MgCl2 with loss of the activity. The CD spectra of the modified enzyme in the near ultraviolet region changed from that of the native enzyme, indicating that aromatic amino acid residues were affected by modification of the SH group. The fluorescence derived from tryptophanyl residue (s) was quenched depending on the extent of modification of the SH group, suggesting that the tryptophanyl residue (s) was located in the proximity of the SH group. The thermostability of the enzyme was remarkably decreased by modification of the SH group.抄録全体を表示PDF形式でダウンロード (460K) -
Toshihiko OKUDA, Shintaro SUGAI1975 年 78 巻 6 号 p. 1241-1246
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーTo study the interaction between carboxyl groups and amino groups in native lysozyme [EC 3. 2. 1. 17], and to identify the positions and the pK values of the abnormal carboxyl groups, N-acetylated lysozyine was prepared. The acetylation did not affect the molecular shape of the enzyme, but changed six amino groups to a non-ionizable form, leaving one amino group free; this was determined to be Lys 33. In addition, pH titration of the acetylated lysozyme in 0.2 or 0.02M KCl aqueous solution indicated fewer titratable groups with pKint of 7.8 or 10.4 compared with the native protein, though the number of titratable carboxyl groups was not affected by the acetylation. From the pH titration results and structural considerations, the untitratable carboxyl groups were suggested to be Asp 48, Asp 66, and Asp 87.
On the other hand, spectrophotometric titration in 0.2M KCl showed that all three tyrosine residues are titratable in the acetylated protein, although an abnormal tyrosine residue exists in the native state. Tyr 20 was suggested to be untitratable in the pH range of 8-12.6.抄録全体を表示PDF形式でダウンロード (408K) -
Amino Acid Sequence of the Peptide Released by Thrombin and the Terminal Residues of the Subunit PolypeptidesShin NAKAMURA, Sadaaki IWANAGA, Tomoji SUZUKI1975 年 78 巻 6 号 p. 1247-1266
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーA blood coagulation factor, Factor XIII, was highly purified from bovine fresh plasma by a method similar to those used for human plasma Factor XIII, The isolated Factor XIII consisted of two subunit polypeptides, a and b chains, with molecular weights of 79, 000±2, 000 and 75, 000±2, 000, respectively. In the conversion of Factor XIII to the active enzyme, Factor XHIa, by bovine thrombin [EC 3. 4. 21. 5], a peptide was liberated. This peptide, designated tentatively as “Activation peptide, ” was isolated by gel-filtration on a Sephadex G-75 column. It contained a total of 37 amino acid residues with a masked N-terminal residue and C-terminal arginine. The whole amino acid sequence of “Activation peptide” was established by the dansyl-Edman method and standard enzymatic techniques, and the masked N-terminal residue was identified as N-acetylserine by using a rat liver acylamino acid-releasing enzyme. This enzyme specifically cleaved the N-acetylserylglutamyl peptide bond of the N-terminal fragment derived from “Activation peptide, ” yielding free N-acetyl-serine and the remaining peptide, which was now reactive to 1-dimethylarnino-naphthalene-5-sulfonyl chloride. A comparison of the sequences of human and bovine “Activation peptide” revealed five amino acids replacements, Ser-3 to Thr; Gly-5 to Arg; Ile-14 to Val; Thr-18 to Asn, and Pro-26 to Leu. Another difference was the deletion of Leu-34 in the human peptide.
Adsorption chromatography on a hydroxylapatite column in the presence of 0.1% sodium dodecyl sulfate was developed as a preparative procedure for the resolution of the two subunit polypeptides, a or a' chain and b chain, constituting the protein molecule of Factor XIII or Factor XIIIa. End group analyses on the isolated pure chains revealed that the structural change of Factor XIII during activation with thrombin occurs only in the N-terminal portion of the a chain, not in the N-terminal end of the b chain or in the C-terminal ends of the a and b chains. From these results, it was concluded that the activation of bovine plasma Factor XIII by thrombin must be accompanied by a limited proteolysis of the arginyl-glycyl bond located in the N-terminal region of the a chain, liberating the “Activation peptide.”
The possibility of activating Factor XIII with other proteinases was examined using Factor Xa [EC 3. 4. 21. 6], Factor Xlla, kallikreins [EC 3. 4. 21. 8], urokinase [EC 3. 4. 99. 26], trypsin [EC 3. 4. 21. 4], ficin [EC 3. 4. 22. 3], papain [EC 3. 4. 22. 2], and bromelain [EC 3. 4. 22. 4]. Among these enzymes, only bromelain and trypsin showed clear activating effects.抄録全体を表示PDF形式でダウンロード (4298K) -
Teruo IWASAKI, Jiro WADA, Toshifumi KIYOHARA, Mitsuyoshi YOSHIKAWA1975 年 78 巻 6 号 p. 1267-1274
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーA low molecular weight active fragment of potato proteinase inhibitor IIb was obtained by incubating the inhibitor with an equimolar amount of trypsin [EC 3. 4. 21. 4] at pH 8 and 30° for 16hr, followed by gel filtration through Sephadex G-50, treatment with trichloroacetic acid, and CM-cellulose chromatography. The purified active fragment consisted of a single peptide chain with a molecular weight of 4, 300, comprising 39 amino acid residues. It retained very strong inhibitory activity against chymotrypsin [EC 3. 4. 21. 1] and subtilisin [EC 3. 4. 21. 14]. However, the yield of this active fragment was rather low and was variable. On further incubation with trvpsin, it was converted into smaller inactive peptides.抄録全体を表示PDF形式でダウンロード (594K) -
Sei-ichi TAKASAKI, Ken-ichi KASAI, Shin-ichi ISHII1975 年 78 巻 6 号 p. 1275-1285
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーThe interaction of bovine thrombin [EC 3. 4. 21. 5] with synthetic substrates and products was studied. The enzyme was purified from Parke-Davis topical thrombin. The purification process afforded some preparations with different clotting specific activities but with similar esterase specific activities. The preparation having highest clotting specific activity and that having lowest clotting activity were tentatively named thrombin-C and thrombin-E, respectively. Kinetic parameters for the hydrolysis of synthetic substrates and normality titrants were determined on the basis of active enzyme quantity, which was assayed by means of a fluorometric normality titrant. It was shown that thrombin-E was acylated by the substrates more slowly than thrombin-C, while deacylation proceeded at similar rates in the two preparations. The results were also compared with those obtained with bovine trypsin [EC 3. 4. 21. 4]. The acylation rates of both thrombin preparations were markedly lower than that of trypsin, while the deacylation rates of the former were only slightly lower than that of the latter. The effects of various product-type inhibitors, such as benzyloxycarbonyl-, benzoyl-, and tosyl-L-arginine, were also examined. Thrombin was affected by these inhibitors not competitively, though trypsin was inhibited competitively.抄録全体を表示PDF形式でダウンロード (855K) -
Makoto KANEDA, Naotomo TOMINAGA1975 年 78 巻 6 号 p. 1287-1296
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーA proteinase from the sarcocarp of melon (Cucumis Melo L. var. Prince) was purified by a three-step procedure involving batch-wise treatment with CM-cellulose fibers, column chromatography on CM-cellulose powder and gel filtration on Sephadex G-75. The final enzyme preparation was homogeneous on acrylamide gel electrophoresis. Its molecular weight was estimated by two different methods to be about 50, 000. Analyses indicated the presence of 475 amino acid residues and at least 7 moles of hexose.
The maximum activity was found in the alkaline pH region against casein as a substrate. The optimum temperature against casein was 70° at pH 7.1.
The enzyme was strongly inhibited by diisopropyl fluorophosphate, partly inhibited by HgCl2 and not inhibited by EDTA, p-chloromercuribenzoic acid, N-tosyl-L-lysine chloromethyl ketone, N-tosyl-L-phenylalanine chloromethyl ketone, and soybean trypsin inhibitor.
The reduced and carboxymethylated insulin B-chain was cleaved at the peptide bonds of Asn3-Gln4, Cm-Cys7-Gly8, Glu13-Ala14, Leu15-Tyr16, Cm-Cys19-Gly20, Phe25-Tyr26, Pro28-Lys29, and Lys29-Ala30 by the enzyme.抄録全体を表示PDF形式でダウンロード (1236K) -
Toshio TAKAGI, Kanenobu KUBO, Junichi ASAKURA, Toshizo ISEMURA1975 年 78 巻 6 号 p. 1297-1300
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーMicelles of sodium dodecyl sulfate (SDS) are significantly retarded by the addition of a small amount of dodecyl alcohol to a sample solution in SDS-polyacrylamide gel electrophoresis. The phenomenon can be ascribed to the decrease in charge density due to the incorporation of dodecyl alcohol into SDS micelles. The effect is extended to SDS-protein polypeptide complexes when the amount of SDS micelles is insufficient to accomodate the dodecyl alcohol. A similar effect is likely to occur when SDS-polyacrylamide gel electrophoresis is applied to a sample containing lipophilic materials.抄録全体を表示PDF形式でダウンロード (2297K) -
Koichi MIZUNO, Tetsuo MAITA, Hisahiro OTA, Genji MATSUDA1975 年 78 巻 6 号 p. 1301-1309
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーThe aminoethylated β polypeptide chain in AII component from the hemoglobin of adult chicken was digested with trypsin [EC 3. 4. 21. 4] and the resulting peptides were separated and purified by ion exchange chromatography, paper chromatography, and gel filtration. Eighteen tryptic peptides, which were nonoverlapping, accounted for all of the amino acid residues in the β polypeptide chain. The amino acid sequences of the tryptic peptides were established by a combination of enzymatic digestion and subtractive Edman degradation.抄録全体を表示PDF形式でダウンロード (551K) -
Tetsuo MAITA, Koichi MIZUNO, Genji MATSUDA1975 年 78 巻 6 号 p. 1311-1319
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーThe aminoethylated β polypeptide chain of AII component from chicken hemoglobin was digested with pepsin [EC 3. 4. 23. 1] and the resulting peptides were separated and purified by gel filtration, ion exchange chromatography, and paper chromatography. The ammo acid composition and partial sequence of the peptic peptides were studied. From the results thus obtained, the primary structure of the β polypeptide chain was established, taking account of the amino acid sequences of the tryptic peptides previously reported.抄録全体を表示PDF形式でダウンロード (467K) -
Toichi EBISUNO, Katsuya SHIGESADA, Hirohiko KATSUKI1975 年 78 巻 6 号 p. 1321-1329
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーD-α-Hydroxyglutarate dehydrogenase of R. rubrum grown anaerobically in the light was partially purified and some properties were investigated.
1. The enzyme catalyzes stoichiometrically the dehydrogenation reaction of D-α-hydroxyglutarate into αa-oxoglutarate, coupled with the reduction of 2, 6-dichlorophenolindophenol.
2. Cytochrome c2, cytochrome c, and ferricyanide are effective as electron acceptors with the crude enzyme but not with the purified one, whereas NAD+ and NADP+ are completely ineffective. The enzyme is thought to play a role in the electron transport system of the organism.
3. D-α-Hydroxyglutarate is virtually the sole substrate for the enzyme. The apparent activity against L-α-hydroxyglutarate is presumed to be due to contamination of the L-isomer sample with the D-isomer. The enzyme shows barely detectable activity against both isomers of malate and virtually no activity against DL-lactate and glycolate.
4. Both isomers of malate and oxalate, which are presumably substrate analogues, inhibit the enzyme activity.
5. The enzyme is not an inducible enzyme but rather is a constitutive one for R. rubrum, unlike from the enzyme of Pseudomonas putida which is an inducible enzyme for the catabolism of lysine.抄録全体を表示PDF形式でダウンロード (700K) -
Kazuo HOSOI, Gilbu SOE, Tomisaburo KAKUNO, Takekazu HORIO1975 年 78 巻 6 号 p. 1331-1346
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリー1. The effects of pH indicators on activities for ATP formation in the light, ATP hydrolysis in the dark and ATP-Pi exchange in the dark were examined with chromatophores from Rhodospirillum rubrum. Of thirty-one pH indicators tested, eleven (metanil yellow, 2, 4-dinitrophenol, ethyl orange, bromocresol green, resazurin, neutral red, bromthymol blue, α-naphtholphthalein, ο-cresolphthalein, phenolphthalein, and alizarin yellow G) almost completely inhibited the activities for ATP formation and ATP-Pi exchange at concentrations of 1mM, and were studied in detail.
2. Of the eleven pH indicators, those other than α-naphtholphthalein, o-cresolphthaleia and phenolphthalein, when assayed at appropriate concentrations, inhibited ATP-Pi exchange, but not ATP hydrolysis. In ATP-Pi exchange, these eight pH indicators at the concentrations described above were competitive against Pi, and non-competitive against ATP. The remaining three kinds of pH indicators were non-competitive against either Pi or ATP, when assayed at concentrations of the dyes that inhibited both activities.
3. The amounts of pH indicators bound with chromatophores were measured. No correlation was found between the amounts of the bound dyes and the extents of their inhibition of either ATP formation or ATP-Pi exchange.
4. Ethyl orange (pKa=4.1) and 2, 4-dinitrophenol (pKa=3.9) stimulated ATP hydrolysis to the greatest extent. The latter dye was hardly bound with chromatophores.
5. The stimulatory effects of pH indicators on ATP hydrolysis were hardly affected by extraction of quinones from chromatophores.
6. Most of the pH indicators stimulated both succinate-cytochrome c2 and NADH-cytochrome c2 reductions in the dark.
7. The mechanism of uncoupling of the electron transfer system and the phosphorylation system by pH indicators and the mechanism of the coupling are discussed.抄録全体を表示PDF形式でダウンロード (1155K) -
Kenichi NAKANO, Keisaku KIMURA, Hiroo INOKUCHI, Tatsuhiko YAGI1975 年 78 巻 6 号 p. 1347-1352
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーAn enzymic electric cell was constructed with a saturated calomel electrode (cathode) and an enzymic electrode (anode) which consisted of a glassy carbon electrode and a mixture containing an NAD-linked dehydrogenase, NAD+, N-methylphenazonium methosulfate and a substrate, and the short-circuit current of the cell was measured. NAD-linked dehydrogenases tested were lactate dehydrogenase [EC 1. 1. 1. 27], alcohol dehydrogenase [EC 1. 1. 1. 1], and malate dehydrogenase [EC 1. 1. 1. 37]. In this cell, electrons from the substrate in the anode mixture were enzymatically transferred to NAD+, and were then transferred to the glassy carbon electrode via N-methyl-phenazonium methosulfate as an intermediary electron carrier, eventually being observed as the short-circuit current of the cell. As long as the enzymic step limited the overall rate of electron transfer, the current was proportional to the amount of the enzyme in the anode container. Thus, the activities of NAD-linked dehydrogenases could be assayed by this “enzymic electric cell method” in the same way as hydrogenase [EC 1. 12. 2. 1] (T. Yagi et al. (1975) J. Biochem. 78, 443-454).抄録全体を表示PDF形式でダウンロード (452K) -
Isao NAGATA, Eisuke FURUYA, Yukuo YOSHIDA, Toku KANASEKI, Kunio TAGAWA1975 年 78 巻 6 号 p. 1353-1364
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (2460K) -
Seiji HAYASAKA, Satoshi HARA, Katsuyoshi MIZUNO1975 年 78 巻 6 号 p. 1365-1367
発行日: 1975/12/25
公開日: 2008/11/18
ジャーナル フリーThe degradation of proteins of the rod outer segment (ROS) fraction by partially purified cathepsin D [EC 3. 4. 23. 5] from the retinal pigment epithelium was studied. The ROS fraction, prepared from bovine eyes by sucrose density gradient centrifugation, had little cathepsin D activity. Partially purified cathepsin D, obtained from a crude extract of bovine retinal pigment epithelium using bovine serum albumin as a substrate, hydrolyzed the proteins of the ROS fraction.
The rate of degradation of ROS proteins was proportional to both the enzyme concentration and the incubation time. With ROS proteins as substrate, the optimal pH of cathepsin D was about 3.5. The degradation of ROS proteins was inhibited by pepstatin.抄録全体を表示PDF形式でダウンロード (187K)
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