巻号一覧
102 巻, 6 号
選択された号の論文の35件中1～35を表示しています
- |<
- <
- 1
- >
- >|
-
Dogan E. GÜVELI1987 年 102 巻 6 号 p. 1329-1332
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーIn this communication we reported the fusion of mitochondria of hepatocytes extracted from a rat liver. It was found that fusion occurred at an electric field of 1.56-1.8 kV/cm at room temperature. Further increase in the field strength (>1.8 kV/cm) was accompanied by the breakdown of mitochondria.抄録全体を表示PDF形式でダウンロード (862K) -
Yasuhiro SAGARA, Yutaka TAKATA, Toshiyuki MIYATA, Takayuki HARA, Tadao ...1987 年 102 巻 6 号 p. 1333-1336
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーcDNA clones for bovine adrenodoxin reductase were isolated, and the primary structure of the enzyme precursor was deduced from their nucleotide sequences. The precursor consists of 492 amino acids including an extrapeptide of 32 amino acids at the amino terminus. The extrapeptide is hydrophobic and rich in arginine. The amino terminal sequence of the precursor is homologous with that of the adrenodoxin precursor. A possible FAD- or NADPH-binding site is present near the amino terminus of the mature enzyme.抄録全体を表示PDF形式でダウンロード (326K) -
Amin SOEBANDRIO, Takachika AZUMA, Yoshio HAMADA, Nobuo SAKATO, Hajime ...1987 年 102 巻 6 号 p. 1337-1343
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーChange in the specificity of anti-(4-hydroxy-3-nitrophenyl) acetyl (NP) antibodies (Abs) with time after immunization was studied. The early anti-NP Abs was specific to the ionized (phenolate) form of NP. The specificity changed with time and the late Abs became able to bind to the protonated (phenolic) form as well as the phenolate form of NP. The nucleotide sequences of mRNA coding for variable regions of heavy and light chains suggested that somatic hypermutation contributed to this change of the specificity.抄録全体を表示PDF形式でダウンロード (503K) -
Retsu MIURA, Yoshihiro MIYAKE1987 年 102 巻 6 号 p. 1345-1354
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe 13C-NMR spectra of the reaction intermediates of D-amino acid oxidase (DAO) were measured with DAO reconstituted with FAD in which the 2-, 4-, 4a-, and 10a-positions of the isoalloxazine moiety were selectively 13C-enriched. The reac-tion intermediates used include charge-transfer complexes of the oxidized DAO with substrate intermediates and those of the reduced enzyme with substrate inter-mediates. For the former type of complex, the reaction intermediates with β-cyano-D-alanine (D-BCNA) and D-proline were used, while for the latter the purple intermediates with D-alanine and D-proline were chosen. The 13C-resonances of 2-13C in the reaction intermediates with D-BCNA and D-proline were downfield-shifted by about 1 ppm relative to the free oxidized DAO. The 4-13C signal for the DAO-D-BCNA intermediate was observed at 1.2 ppm upfield from that of the oxidized DAO, though that for DAO-D-proline intermediate showed no shift. These results suggest modulation of the hydrogen bondings at C (2) =0 and/or C (4) =0 in these reaction intermediates. Comparison of the 13C-resonances of reduced DAO with those of free reduced FMN in the neutral and anionic forms indicate that FAD in reduced DAO is in the anionic reduced form. The 4a-13C resonance of reduced DAO is upfield-shifted by about 3 ppm from that of free reduced anionic FMN. Comparison of the 13C-resonances for the purple intermediates with those of reduced FMN and reduced DAO indicate unequivocally that FAD in the purple intermediate is in the anionic reduced state. The 4a-13C resonances for the purple intermediates were substantially upfield-shifted (by 2.4 ppm with D-alanine and 1.9 ppm with D-proline) relative to reduced DAO. This indicates that the electron density, and hence the nucleophilicity, of the 4a-carbon is elevated in the purple intermediate relative to free reduced DAO. This leads to a model in which the oxidative half reaction proceeds via the reaction of molecular oxygen at the 4a-position of the reduced FAD in the purple intermediate. This provides a rational molecular basis for the oxidative half reaction by way of the purple intermediateprior to product release rather than by way of free reduced enzyme after product release.抄録全体を表示PDF形式でダウンロード (749K) -
Satoru MURAYAMA, Junko UMEZAWA, Jun TERAJIMA, Bunei SYUTO, Shuichiro K ...1987 年 102 巻 6 号 p. 1355-1364
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe action of botulinum neurotoxin type C1, on the release of acetylcholine from rat brain synaptosomes was studied by using anti-toxin heavy chain Fab and anti-toxin light chain Fab. The toxin was bound to synaptosomes at 0°C for 10 min, in which [14C] acetylcholine had been accumulated previously. The toxin-binding synapto-somes were pre-incubated at 37°C, and the release of acetylcholine was determined after the synaptosomes had been incubated in 25 mM KCl-incubation medium for 20 min at 37°C. Inhibition of [14C] acetylcholine release from the synaptosomes was observed with increasing pre-incubation time and toxin concentration, and the maximum inhibition was seen after preincubation for at least 15 min, which was called the “lag time.” The toxin-binding synaptosomes were reacted with anti-toxin heavy chain and anti-toxin light chain Fabs at 0°C for 1.5 min before preincubation of the synaptosomes at 37°C. Both Fabs reversed the acetylcholine release inhibi-tion by the toxin. However, when the Fabs were added during the pre-incubation time at 37°C, they showed less restoration with increasing pre-incubation time. The restoration was completely abolished if the Fabs were added to the synapto-somes after the first half of the “lag time.” On the other hand, when 125I-labeled toxin-binding synaptosomes were reacted with the Fabs at 0°C for 1.5 min before pre-incubation of the synaptosomes at 37°C, anti-heavy chain Fab removed 125I-toxin from the synaptosomes, but anti-light chain Fab did not. However, if the Fabs were added to toxin-binding synaptosomes during the pre-incubation time at 37°C, the Fabs could not remove 125I-toxin from the synaptosomes, and thesynaptosomes retained more labeled toxin with increasing pre-incubation time. These results suggest that there are three distinct steps in the inhibition of acetyl-choline release from synaptosomes by botulinum neurotoxin. The first is binding, which is reversible, temperature-independent, and mediated by the heavy chain of the toxin. The second is temperature-dependent internalization, that takes place in the first half of the “lag time, ” in which both the chains are internalized into synaptosomes. The third is the development of toxicity, which requires the latter half of the “lag time.”抄録全体を表示PDF形式でダウンロード (829K) -
Akira INOUE, Youtaro HIGASHI, Munehiko YUKIOKA, Seiji MORISAWA1987 年 102 巻 6 号 p. 1365-1370
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーRifamycin AF/013, a potent inhibitor of nucleic acid polymerizing enzymes and of some hormone receptors, strongly inhibited thyroid hormone-binding to the isolated nuclear receptor. Fifty percent inhibition was obtained at AF/013 con-centration of as low as 8 μg/ml. AF/013, however, only weakly promoted dissocia-tion of the bound hormone from the receptor. The inhibitory action of AF/013 was competitive with respect to and reduced the receptor's affinity for the hormone.抄録全体を表示PDF形式でダウンロード (468K) -
Tomoko INOUE, Kazuyuki AKASAKA1987 年 102 巻 6 号 p. 1371-1378
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe self association of Streptomyces subtilisin inhibitor, a dimeric protein molecule of MW 23, 000 in an aqueous environment has been investigated by the combined use of sedimentation equilibrium analysis and 1H nuclear magnetic resonance (NMR) spectroscopy. A significant degree of self association was found using the sedi-mentation equilibrium method in the concentration range between 5 and 20mg/ml. Furthermore, the use of 1H NMR spectroscopy in conjunction with the sedi-mentation equilibrium method enabled us to study the self association in a much higher concentration range (up to 60mg/ml or more). The self association reaction in the concentration range of 10-40mg/ml fits reasonably well a “successive poly-merization model”in which each step of the polymerization reaction consists of the addition of one intrinsic dimer of Streptomyces subtilisin inhibiter to the previ-ously formed polymeric species, with an equilibrium constant common to all the steps of 400 M-1. The 1H NMR chemical shift and line broadening data show that the dimer-dimer interaction probably involves the reactive-site segment of this inhibitor without a significant conformational change in the major part of the protein structure.抄録全体を表示PDF形式でダウンロード (606K) -
Jin KONISHI, Takayoshi WAKAGI, Tairo OSHIMA, Masasuke YOSHIDA1987 年 102 巻 6 号 p. 1379-1387
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA novel ATPase was solubilized from membranes of an acidothermophilic archae-bacterium, Sulfolobus acidocaldarius, with low ionic strength buffer containing EDTA. The enzyme was purified to homogeneity by hydrophobic chromatography and gel filtration. The molecular weight of the purified enzyme was estimated to be 360, 000. Polyacrylamide gel electrophoresis of the purified enzyme in the pres-ence of sodium dodecyl sulfate revealed that it consisted of three kinds of subunits, α, β, and γ, whose molecular weights were approximately 69, 000, 54, 000, and 28, 000, respectively, and the most probable subunit stoichiometry was α3β3γ1. The purified ATPase hydrolyzed ATP, GTP, ITP, and CTP but not UTP, ADP, AMP, or p-nitrophenylphosphate. The enzyme was highly heat stable and showed an optimal temperature of 85°C. It showed an optimal pH of around 5, very little activity at neutral pH, and another small activity peak at pH 8.5. The ATPase activity was significantly stimulated by bisulfite and bicarbonate ions, the optimal pH remaining unchanged. The Lineweaver-Burk plot was linear, and the Km for ATP and the Vmax were estimated to be 1.6 mM and 13 μmol P1•mg•-1•min-1, respectively, at pH 5.2 at 60°C in the presence of bisulfite. The chemical modification reagent, 7-chloro-4-nitrobenzo-2-oxa-1, 3-diazole, caused inactivation of the ATPase activity although the enzyme was not inhibited by N, N'-dicyclohexylcarbodiimide, N-ethyl-maleimide, azide or vanadate. These results suggest that the ATPase purified from membranes of S. acidocaldarius resembles other archaebacterial ATPases, although a counterpart of the γ subunit has not been found in the latter. The relationship of the S. acidocaldarius ATPase to other ion-transporting ATPases, such as F0F1, type or E1E2 type ATPases, was discussed.抄録全体を表示PDF形式でダウンロード (1377K) -
Hisao KATO, Eiji NAKANISHI, Kei-ichi ENJYOJI, Izumi HAYASHI, Sachiko O ...1987 年 102 巻 6 号 p. 1389-1404
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーFrom the homogenate of rat submaxillary gland, two kinds of serine proteinases, named tentatively proteinases A and B. were isolated and their chemical properties and activities toward rat kininogens were examined, in comparison with those of submaxillary kallikrein. Proteinase A with Mr of 28, 200 rapidly cleaved high-molecular-weight (HMW) kininogen into a protein of 67 kDa, which retained thiol-proteinase inhibitory activity, but had lost the correcting activity of HMW kininogen on the prolonged clotting time of Fitzgerald trait plasma. It liberated bradykinin from HMW kininogen but did not liberate kinin from T-kininogen and did not degrade T-kininogen. On the other hand, proteinase B with Mr of 30, 400 showed a very weak activity for the liberation of kinin from T-kininogen and the cleavage of T-kininogen at pH 8.0. However, the enzyme extensively degraded T-kininogen at pH 4.5. Proteinase B also degraded HMW kininogen at pH 4.5 and pH 8.0, but liberated bradykinin only at pH 8.0. Thiol-proteinase inhibitory activities of HMW kininogen and T-kininogen were inactivated after the incubation with proteinase B at pH 4.5 but not at pH 8.0, while the correcting activity of HMW kininogen on the Fitzgerald trait plasma was inactivated at pH 4.5 and 8.0. The NH2-terminal amino acid sequences of proteinases A and B were different from each other, and distinguishable with those of serine proteinases in rat submaxillary gland so far reported. These results provide evidence that in addition to the known kallikrein, there exist at least two kinds of serine proteinases in rat submaxillary gland, both of which liberate bradykinin from rat HMW kininogen at pH 8.0 and modulate the functional activities of HMW kininogen and T-kininogen, degrading these proteins at pH 8.0 or 4.5.抄録全体を表示PDF形式でダウンロード (3696K) -
Hisakazu FUJITA, Yusuke MIZUNO, Hiroyuki SHIOKAWA1987 年 102 巻 6 号 p. 1405-1414
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーAcylphosphatase has been purified from porcine testis and its properties were compared with those of porcine skeletal muscle acylphosphatase. The molecular weight of the testis enzyme was found to be 10, 600, similar to that of porcine skeletal muscle acylphosphatase, on sedimentation equilibrium analysis. The specific activity of the testis enzyme was 10, 800 μmol/min/mg at 25°C with benzoyl phosphate as substrate, i.e., higher than that of the muscle enzyme, 7, 200 μmol/min/mg, under the same conditions. The pI of the testis enzyme was 8.3, i.e., lower than that of the muscle enzyme, 10.6. There were marked differences in the amino acid compositions of the two enzymes. In particular two histidine residues were present in the testis enzyme but none were present in the muscle enzyme, and no cysteine residue was present in the testis enzyme but one was present in the muscle enzyme. The carboxyl terminal amino acid of the testis enzyme seemed to be lysine, while that of the muscle enzyme is tyrosine. The peptide maps of the testis and muscle enzymes indicated considerable differences in the amino acid sequences of the two enzymes. Differences in the antigenic structures of the two enzymes were demonstrated on enzyme linked immunoassaying and double immunodiffusion. These results indicate that the porcine testis acylphosphatase is an isozyme different from the porcine skeletal muscle acylphosphatase.抄録全体を表示PDF形式でダウンロード (2502K) -
Esteban MONTEJO de GARCINI, Jesús AVILA1987 年 102 巻 6 号 p. 1415-1421
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーOne of the microtubule associated proteins, tau factor, that appears associated to the paired helical filaments of Alzheimer's disease presents, by itself, after urea treatment, the ability of polymerizing in vitro as tested by immunoelectronmicroscopy. These polymers resemble in their width and appearance those of the paired helical filaments. The conditions required for this assembly have been studied and determined the protein concentration needed, the influence of salt concentration and pH as well as the possible modifications (deamination, acylation) which may be implied in such in vitro polymerization.抄録全体を表示PDF形式でダウンロード (2731K) -
Yoshiki HABU, Masato NAGAOKA, Teruo YOKOKURA, Ichiro AZUMA1987 年 102 巻 6 号 p. 1423-1432
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe chemical compositions of the cell walls obtained from 8 strains in 5 species of Bifidobacterium were analyzed. These cell walls were shown to be composed of peptidoglycan and polysaccharide moieties. Some variations with respect to contents of neutral sugars and content of phosphorus were observed with some cell wall preparations from the same species. The neutral polysaccharides in cell walls of 4 strains of Bifidobacterium (B. bifidum YIT 4007, B. breve YIT 4010, B. infantis YIT 4025, and B. longum ATCC 15707) were purified and their chemical structures were analyzed. One of these polysaccharides, obtained from B. breve YIT 4010, was analyzed in detail by GLC, 1H- and 13C-NMR spectroscopic analyses, methylation, Smith degradation and acetolysis, and the results suggested the following structure for the repeating unit of the polysaccharide:_??_抄録全体を表示PDF形式でダウンロード (741K) -
Eiro MUNEYUKI, Koki OHNO, Yasuo KAGAWA, Hajime HIRATA1987 年 102 巻 6 号 p. 1433-1440
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーProton translocating ATPase (FoF1) from bovine heart mitochondria was reconstituted into planar phospholipid bilayers, and its electrogenicity was directly demonstrated. The FoF1, ATPase was solubilized using 3-[(3-cholamidopropyl)-dimethyl-ammonio]-1-propanesulfonic acid (CHAPS) as a detergent followed by sucrose density gradient centrifugation according to the method originally described by McEnery et al. for rat liver mitochondria (McEnery et al. (1986) J. Biol. Chem. 259, 4642-4651), with minor modifications. The purified ATPase was reconstituted into proteoliposomes and then reconstituted into planar phospholipid bilayers by the modified fusion method (Hirata et al. (1986) J. Biol. Chem. 261, 9839-9843). A short-circuit current of up to 0.4 pA was induced by adding ATP, and this current was suppressed by the F1, ATPase inhibitor NaN3 or by a specific mitochondrial Fo inhibitor, oligomycin. The direction of the current corresponded to the flow of positive charges from the F1, side to the Fo side. All these facts clearly demonstrate that the mitochondrial FoF1 ATPase was successfully reconstituted into planar phospholipid bilayers, and the current was generated by the ATPase.抄録全体を表示PDF形式でダウンロード (652K) -
Naoko ODA, Hironori SAKAI, Tiee-Cherng SHIEH, Hiroko NAKAMURA, Shunji ...1987 年 102 巻 6 号 p. 1441-1449
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーPhospholipase A2 was purified to homogeneity from the venom of Trimeresurus gramineus (the Green Habu snake) via three steps consisting of Sephadex G-75, DEAF-cellulose, and DEAE-Toyopearl 650M column chromatographies. Molecular weight determinations showed that the enzyme consists of a single polypeptide chain with a molecular weight of approximately 14, 000. The isoelectric point was 4.5. The enzyme is characterized by high contents of acidic amino acids, glycine, and half-cystine. Calcium ion was essential for eliciting activity. The enzyme was inactivated by alkylation of a single histidine residue with p-bromophenacyl bromide following pseudo first-order kinetics, and the rate of the inactivation was depressed in the presence of Ca2+. The N-terminal sequence of this enzyme determined to the 40th residue was found to be highly homologous to that of Trimeresurus okinavensis phospholipase A2 but not to that of Trimeresurus flavoviridis phospholipase A2. The phenylalanine residue at the 27th position of T. gramineus phospholipase A2 is noteworthy because all other phospholipases A2, with only two exceptions, contain a tyrosine residue at this position.抄録全体を表示PDF形式でダウンロード (1432K) -
Nobuhiro MORISHIMA, Atsushi IKAI1987 年 102 巻 6 号 p. 1451-1457
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーFour kinds of active sites of bacterial fatty acid synthetase were mapped on distinct regions within a subunit. Active sites were specifically labeled with radioactive substrates and active-site-directed inhibitors. Labeled enzymes were cleaved with proteases, and the fragments thus produced were identified with respect to specific labels by SDS-polyacrylamide gel electrophoresis and a fluorographic technique. The linear alignment of such fragments in the original subunit was established and when the results were combined with those of our previous work, five active sites were located in three regions as follows. Starting from the N-terminal of the sub-unit, we located acetyl, malonyl and palmitoyl transferases in the first region, the acyl carrier site in the second region (Morishima & Ikai (1985) Biochim. Biophys. Acta 832, 297-307), and β-ketoacyl synthetase in the third region. The observed order of active sites of bacterial fatty acid synthetase can be correlated with that of the yeast enzyme, which has two kinds of subunits.抄録全体を表示PDF形式でダウンロード (2688K) -
Miyuki KATOH, Sachiko AONO, Hiroomi KEINO, Shigeo KASHIWAMATA1987 年 102 巻 6 号 p. 1459-1468
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe time-dependent changes in the chromatographic pattern of subcutaneously injected cadmium associated with non-metallothionein cadmium-binding proteins were studied in the rat liver cytosol. Prior to the induction of cadmium-thionein (less than 3h), cadmium appeared in three major peaks (P-1 with the void volume, P-2 and P-3) on Sephacryl S-300 column chromatography. Accompanied with the emergence of apo-metallothionein (about 3h after administration), the amount of P-3 decreased and instead a cadmium-thionein peak (P-4) increased. Ion-exchange chromatography of P-3 with a combination of CM and DEAE Bio-Gel columns showed the existence of three major cadmium-binding proteins with molecular sizes of 46kDa (in the CM Bio-Gel column eluate), 50kDa (in the DEAE Bio-Gel column eluate), and 41kDa (in the non-adsorbed fraction). The cadmium-binding protein in the CM Bio-Gel column eluate was purified to apparent homogeneity. The purified protein (CM-CdP) was 47 or 53kDa in molecular size as determined by SDS-polyacrylamide gel electrophoresis or gel filtration chromatography, respectively. The apparent dissociation constant and maximum binding for cadmium were about 1μM and 1mol of the metal/mol of protein, respectively. The isoelectric point was estimated to be 8.8. The amino acid composition showed that the protein was relatively rich in glutamyl (including its amide) and alanyl residues. The N-terminal amino acid sequence was determined as Ala-Pro-Ile-Ala-Gly-Lys-Lys-Ala-Lys-Ala-Gly-Ile-Leu-Leu-Gly-. In-vitro experiments revealed that cadmium bound to CM-CdP could be easily transferred to apo-metallothionein, confirming that the affinity for the metal of the former protein was lower than that of the latter.抄録全体を表示PDF形式でダウンロード (1374K) -
Kazuhiko YUKIOKA, Shuzo OTANI, Isao MATSUI-YUASA, Tadayoshi SHIBATA, Y ...1987 年 102 巻 6 号 p. 1469-1476
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーDL-a-Difluoromethylornithine (DFMO), a specific inhibitor of ornithine decarboxylase [EC 4.1.1.17] (ODC), inhibited concanavalin A-induced proliferation of splenic mononuclear cells (SMNC). The inhibition was not reversed by interleukin-2 (IL-2) addition. Although DFMO did not affect the production of IL-2 or the expression of high-affinity IL-2 receptor, IL-2-dependent proliferation of SMNC was inhibited by DFMO, and the inhibition was reversed by exogenous putrescine. The inhibition of IL-2-dependent DNA synthesis appeared to be related to the decrease in intracellular polyamines. When the proliferation of SMNC was induced by IL-2, ODC activity was also increased. A similar result was obtained in the proliferation of an IL-2-dependent T cell line, CTLL. The time course of ODC induction was similar to that of IL-2 production by concanavalin A-stimulated SMNC. These results indicate that polyamine biosynthesis is necessary for IL-2-dependent proliferation, but not for IL-2 production or IL-2 receptor expression.抄録全体を表示PDF形式でダウンロード (612K) -
Etsuko YASUGI, Takeshi KASAMA, Yousuke SEYAMA1987 年 102 巻 6 号 p. 1477-1482
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーCerebrosides obtained from the guinea pig Harderian gland were analyzed. The purified cerebrosides gave a single spot on thin-layer chromatography, the Rf value being similar to that of phrenosine obtained from whale brain. The cerebrosides consisted of 74.7% of glucosylceramide and 25.3% of galactosylceramide. The fatty acid composition of these cerebrosides was 0.7% of non-hydroxy fatty acids and 99.3% of a-hydroxy fatty acids. Among these a-hydroxy fatty acids, a small amount of methyl branched acids was detected. The substituted position of methyl branching of a-hydroxy fatty acids was the 16th carbon atom from the carboxyl end irrespective of the carbon chain length. The long chain bases were composed of sphinganine (78%) and sphingenine (22 %). 4-D-Hydroxysphinganine was not found. The most remarkable feature of the long chain bases of cerebrosides in the Harderian gland was the presence of a large amount of methyl branched sphinganine. The cerebrosides obtained from the cerebrum and cerebellum of the same animal were also analyzed. The sugar, fatty acid, and long chain base compositions of these cerebrosides were similar to those of whale brain cerebrosides. Methyl branched sphinganine was not found in guinea pig brain.抄録全体を表示PDF形式でダウンロード (1156K) -
Yukio MITSUI, Hideo HIGUCHI, Shinako TERASHIMA, Seizo TAKAHASHI, Di Hu ...1987 年 102 巻 6 号 p. 1483-1487
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーConnectin is a very long and flexible protein of striated muscle, linking myosin filaments to z discs in a sarcomere. Isolated native connectin in solution frequently forms elastic threads upon concentration of the solution, by side-by-side association of molecules. An X-ray diffraction study was performed to examine the presence of β-sheet structure in artificially prepared threads. The elastic properties of such threads were measured at various temperatures. Negative temperature dependence of the elastic coefficient suggests that the elasticity of connectin threads is due to deformation of the three-dimensional structure and not to rubber-like behavior.抄録全体を表示PDF形式でダウンロード (1057K) -
Atsushi ISHII, Toshiro OCHIAI, Shigeki IMAGAWA, Noriyuki FUKUNAGA, Sho ...1987 年 102 巻 6 号 p. 1489-1498
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーEach of the two isozymes, which are different in thermostability and quaternary structure, of isocitrate dehydrogenase (NADP+) [IDH: EC 1.1.1.42] was purified to an electrophoretically homogeneous state from an obligately psychrophilic marine bacterium, Vibrio sp. strain ABE-1. Hydrophobic chromatography was an efficient procedure to separate the two isozymes from each other. The isoelectric points of isozyme I (IDH-I; a dimer, Mr 88, 100) and isozyme II (IDH-II; a monomer, Mr 80, 500) were found to be pH 4.9 and 5.2, respectively. The two isozymes were similar in amino acid compositions, though there were slight differences in the contents of nonpolar and hydroxyl amino acids. However, their NH2-terminal amino acid sequences and immunochemical properties were clearly different from each other. The NH2-terminal amino acid sequence analysis also indicated that the subunits of IDH-I are chemically identical or highly homologous. Non-immuno-crossreactivity between the isozymes enabled us to measure the intracellular contents of the isozymes. IDH-I and -II were found to be differentially regulated in vivo by various growth conditions. IDH-I was induced by acetate, while IDH-II re-mained almost unchanged.抄録全体を表示PDF形式でダウンロード (1923K) -
Yuko TAWADA, Ken-Ichi FURUKAWA, Munekazu SHIGEKAWA1987 年 102 巻 6 号 p. 1499-1509
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーTo characterize the excitatory purinoceptors in vascular smooth muscle cells and the biochemical mechanisms of their actions, the effects of ATP and other nucleotides on Ca2+ mobilization in cultured smooth muscle cells mainly from rat aorta were investigated. ATP induced a transient and dose-dependent increase in the cytosolic Ca2+ concentration. ATP also induced a rapid production of inositol trisphosphate (IP3). The agonist form of ATP was metal-free ATP and its half-maximal effect was obtained at about 0.1 μM. 4-β-Phorbol 12-myristate 13-acetate (PMA) or 8-(N, N-diethylamino)octyl-3, 4, 5-trimethoxybenzoate (TMB-8) inhibited both Ca2+ response and IP3, production. In addition, TMB-8 but not PMA, significantly decreased the amount of releasable Ca2+ presumably in the sarcoplasmic reticulum. Pertussis toxin also inhibited the Ca2+ response. Based on the dose-dependent effects of various nucleotides and adenosine on the Ca2+ response, it was concluded that the P2 subclass of purinoceptor is involved in the observed ATP effects. In addition, the observed absence or very weak effect of α, β-methylene ATP relative to the effect of ATP suggests that the excitatory P2-purinoceptors in vascular smooth muscle cells do not form a homogeneous group, because the opposite order of potency for these two nucleotides was reported previously for the P2 purinoceptors involved in contraction of some isolated blood vessels.抄録全体を表示PDF形式でダウンロード (825K) -
Koh IBA, Ken-ichirou MOROHASHI, Toshiyuki MIYATA, Ken-ichiro TAKAMIYA1987 年 102 巻 6 号 p. 1511-1518
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe structural gene coding for cytochrome b-562 isolated from the cytochrome b-c1, complex of Rhodobacter (Rhodopseudomonas) sphaeroides has been cloned. Its nucleotide sequence has been determined and the amino acid sequence was deduced therefrom. It consists of 157 amino acids (Mr 17, 237) and contains four hydrophobic segments. The first 30 residues in the predicted amino acid sequence are the same as those determined for the NH2-terminal portion of purified cytochrome b-562. The amino acid composition is in accord with that determined for the pure protein. From the hydropathy profile and molar ratio of protoheme to cytochrome b-562, it is suggested that the structural and functional unit of the cytochrome is a two-heme cross-linked homodimer.抄録全体を表示PDF形式でダウンロード (589K) -
Yasuo KIKUCHI, Kenichi YASUMOTO, Karl MEYER1987 年 102 巻 6 号 p. 1519-1524
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーKeratan sulfate II was prepared from the proteolytic digest of pig nucleus pulposusproteoglycan. The polysaccharide chains containing the fragment peptides of the core protein at their reducing terminal were subjected to anhydrous HF-solvolysis reaction and one of the glycopeptides from the keratan sulfate II-core protein linkage regions was isolated. The amino acid sequence of the peptide was deduced to be Ala-Pro-Ser-Pro-Gly, which is different from those reported for the attachment sites of chondroitin sulfate on core proteins from various sources. The results provided the first solid amino acid sequence for the keratan sulfate II-core protein linkage regions and suggested that the amino acid sequence of the core protein might determine the distribution of chondroitin sulfates and keratan sulfates along the core protein of the proteoglycan molecule.抄録全体を表示PDF形式でダウンロード (437K) -
Mizuho UNE, Yusaku TAZAWA, Keiya TADA, Takahiko HOSHITA1987 年 102 巻 6 号 p. 1525-1530
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーUrine from a patient with Zellweger's syndrome was examined for bile acids after fractionation into three groups according to mode of conjugation. 3α, 7α, 12α-Trihydroxy-5β-cholestanoic acid was the predominant bile acid of the unconjugated and glycine-conjugated bile acid fractions. Smaller amounts of cholic acid and 1β-, 6α-, 24-, and 26-hydroxylated derivatives of 3α, 7α, 12α-trihydroxy-5β-cholestanoic acid were found in both fractions in similar proportions. The bile acid spectrum of the taurine-conjugated bile acid fraction was different from those of the other two fractionsin the occurrence of two new compounds as the major constituents. These compounds were tentatively identified as two epimers at C-23 of 3α, 7α, 12α-trihydroxy-5β-cholestano-26, 23-lactone, which were probably artifacts formed from the corresponding tetrahydroxycholestanoic acids during the procedures for extraction after hydrolysis. High-performance liquid chromatographic analysis revealed that 3α, 7α, 12α-trihydroxy-5β-cholestanoic acid excreted into the urine as the unconjugated form consisted of a mixture of (25R)- and (25S)-isomers in the ratio of about 7:3.抄録全体を表示PDF形式でダウンロード (478K) -
Ying LUAN, Isao MATSUURA, Michio YAZAWA, Taro NAKAMURA, Koichi YAGI1987 年 102 巻 6 号 p. 1531-1537
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーCalmodulin of the baker's yeast (Saccharomyces cerevisiae) showed a similar affinity for Ca2+ to that of vertebrate calmodulin. The maximum binding number of Ca2+ to yeast calmodulin was, however, 3 mol/mol, which is lower than that of vertebrate calmodulin (4 mol/mol). The same maximum activity of porcine brain phospho-diesterase was attained when 100 times higher concentration of yeast calmodulin than that of vertebrate calmodulin was added. On the other hand, the maximum activation of chicken gizzard myosin light chain kinase was attained with 1, 000 times higher concentration of yeast calmodulin than that of vertebrate calmodulin, and the maximum activity with yeast calmodulin was less than 1/5 of that with vertebrate calmodulin. Several amino acid substitutions observed in the yeast calmodulin, particularly at the a-helical rod connecting the two globular domains, may affect the interaction mode of various target enzymes with this calmodulin.抄録全体を表示PDF形式でダウンロード (556K) -
Takashi KUMAZAKI, Kumiko TERASAWA, Shin-ichi ISHII1987 年 102 巻 6 号 p. 1539-1546
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーRecently we have succeeded in the efficient isolation of the C-terminal peptides from tryptic digests of the tail sheath protein (with C-terminal Gly) and the tube protein (with C-terminal Glu) of bacteriophage T4, by taking advantage of a unique property of immobilized anhydrotrypsin, that is, a strong specific affinity for peptides containing Arg or Lys residues at their C-termini. In this study, the utility of affinity chromatography on immobilized anhydrotrypsin was further demonstrated in the cases of Streptomyces subtilisin inhibitor (as a reduced and S-carboxymethylated form, with C-terminal Phe) and arantitrypsin (with C-terminal Lys). By subjecting a tryptic digest of the former protein and a chymotryptic digest of the latter protein to the affinitychromatography, the C-terminal peptides were specifically recovered in the breakthrough fraction and in the adsorbed fraction, respectively. It was further shown that immobilized anhydrotrypsin can also adsorb peptides with C-terminal S-aminoethyl-Cys residues and exerts adsorptive ability even toward the peptides in solution containing urea at a high concentration if appropriate pre-cautions are taken. These findings suggest the general utility of this simple method for C-terminal peptide isolation, which is extremely helpful for studies to confirm amino acid sequences deduced from nucleotide sequences of the cDNA (or genomic DNA) of proteins.抄録全体を表示PDF形式でダウンロード (651K) -
Hidetoshi YOSHIMURA, Yumiko HOKAMA, Ikuo WADA, Nobuyuki KOGA, Shin'ich ...1987 年 102 巻 6 号 p. 1547-1554
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーDT-Diaphorase purified from the liver cytosol of rats treated with a highly toxic PCB congener, 3, 4, 5, 3', 4'-pentachlorobiphenyl (PenCB), was compared to those from 3-methylcholanthrene (MC)-treated and untreated rats. Treatments with PenCB and MC resulted in about 8- and 7-fold increases of cytosolic DT-diaphorase activity, respectively. Purification of the enzyme preparations from untreated, and PenCB- and MC-treated rats were conducted by using DE-52, DEAE-Sephadex A-50, hydroxylapatite, and Bio-Gel P-150 column chromatographies. Both Sephadex G-100 gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that all of the final preparations from the three origins were homogeneous and had the same molecular weight of 59, 000, consisting of two subunits with molecular weights of 30, 000. Further studies on amino acid composition, Km value, optimum pH, and catalytic activities for various substrates also indicated that both PenCB- and MC-inducible DT-diaphorases were identical with that from the untreated rats. All three DT-diaphorases contained about 2 mol of FAD per mol of enzyme. Partial digestion of the enzymes by trypsin and subsequent analysis by HPLC revealed that the three preparations were indistinguishable. The identity among the three purified DT-diaphorases was finally confirmed by Ouchterlony immunodiffusion employing anti-serum raised against each enzyme preparation.抄録全体を表示PDF形式でダウンロード (1090K) -
Yoshiharu SHIRASU, Hideaki YOSHIDA, Shigeru MATSUKI, Kazuta TAKEMURA, ...1987 年 102 巻 6 号 p. 1555-1563
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーWe have cloned a DNA that is complementary to the messenger RNA that encodes human pancreatic elastase 2 from a human pancreatic cDNA library using a cloned cDNA for rat pancreatic elastase 2 messenger RNA. This complementary DNA contains the entire protein coding region of 807 nucleotides which encodes prepro-elastase of 269 amino acids, and 4 and 82 nucleotides of the 5'- and 3'-untranslated sequences, respectively. When this deduced amino acid sequence was compared with known amino acid sequences it showed 82% homology with rat pancreatic elastase 2. This deduced sequence also contains a 16-amino-acid peptide identical with the N-terminal sequence determined for native human pancreatic proelastase 2. Taking the above findings together, we conclude that the cloned cDNA encodes a mature enzyme of 241 amino acids including 16 and 12 amino acids for a signal peptide and an activation peptide, respectively. Moreover, the predicted key amino acid residues involved in determining the substrate specificity of mammalian pan-creatic elastase 2 are retained in the human enzyme. Cloned human pancreatic elastase 2 cDNA was expressed in E. coli as a mature and pro-form protein. Both resulting proteins showed immunoreactivity toward anti-elastase serum and enzy-matic activity. We have also cloned and sequenced a porcine pancreatic elastase 2 cDNA.抄録全体を表示PDF形式でダウンロード (1300K) -
Kazuhiro MITSUI, Mitsuyoshi MOTIZUKI, Yaeta ENDO, Sadaki YOKOTA, Kunio ...1987 年 102 巻 6 号 p. 1565-1570
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA new ribosomal protein of 38 kDa, named A0, was detected in yeast ribosomes on immunoblotting. The antibody used here was that against Al/A2, 13 kDa acidic ribosomal proteins which cross-reacted with A0. Although A0 and Al/A2 share common antigenic determinants, they differ in the following biochemical properties. While Al/A2 could be extracted from ribosomes with ethanol and ammonium sulfate, A0 could not. A0gave two protein spots in a less acidic region than for Al/A2 on two-dimensional gel electrophoresis. The heterogeneity observed for A0was ascribable to phosphorylation because one spot disappeared after treatment of the ribosomes with phosphatase. The syntheses of A0and Al/A2 are directed by different mRNA species, as judged with a cell-free translation system, ruling out the possibility that A0 is a precursor of Al/A2. Although a mammalian ribosomal protein equivalent to A0 has been shown to be associated with 13 kDa acidic pro-teins in the cytoplasm, essentially no A0 was detected on immunoblotting in the yeast cytosol, while a small but detectable amount of Al/A2 was present. The possibility that A0 is a eukaryotic equivalent of L10 of Escherichia coli is discussed.抄録全体を表示PDF形式でダウンロード (1633K) -
Masafumi TSUJIMOTO, Jan VILCEK1987 年 102 巻 6 号 p. 1571-1577
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーTumor necrosis factor (TNF) induced loss of TNF receptors in HeLa cells was studied using acid elution technique, which could distinguish surface occupancy and real loss of receptors. Exposure of HeLa cells to TNF resulted in a rapid reduction in the number of TNF receptors without affecting the apparent binding affinity. The binding of transferrin after treatment with unlabeled TNF was un-affected. The TNF-mediated decrease in receptor number on the cells was reversi-ble. Following removal of TNF from growth medium, binding activity was restored within 3 h. Cycloheximide prevented the restoration of TNF receptors, suggesting that de novo synthesis of receptors was required to restore the binding activity.抄録全体を表示PDF形式でダウンロード (509K) -
Terutaka TSUDA, Yasuo FUKUMOTO, Yasuo HAMAMORI, Takayuki YAMASHITA, Yo ...1987 年 102 巻 6 号 p. 1579-1583
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーIncubation of human promyelocytic leukemia (HL-60) cells with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), a protein kinase C-activating phorbol ester, caused a marked increase in c-fos mRNA in a dose-dependent manner. Phorbol-12, 13-dibutyrate and 1-oleoy1-2-acetyl-glycerol, other protein kinase C-activating agents, were also active in this capacity. 4a-Phorbol-12, 13-didecanoate, known to be inactive for protein kinase C, was ineffective. 8-Bromo-cyclic AMP (8-Br-cAMP) also increased c-fos mRNA in a dose-dependent manner. This action of 8-Br-cAMP was mimicked by prostaglandin E2, which is known to raise the cyclic AMP level in HL-60 cells. c-fos mRNA increased within 15 min and reached a maximal level 45 min after the stimulation of the cells by TPA or 8-Br-cAMP. The simultaneous stimulation of the cells by TPA and 8-Br-cAMP at the respective doses giving maxi-mal elevation of c-fos mRNA increased this mRNA in an additive manner. These results suggest that in HL-60 cells expression of the c-fos gene is regulated independ-ently by two different intracellular messenger systems, protein kinase C and cyclic AMP.抄録全体を表示PDF形式でダウンロード (897K) -
Akira HARA, Toshihiro NAKAYAMA, Makoto NAKAGAWA, Yoshio INOUE, Hiroyuk ...1987 年 102 巻 6 号 p. 1585-1592
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe kinetic mechanism of two major monomeric 17β-hydroxysteroid dehydrogenases from mouse liver cytosol was studied at pH 7 in both directions with NADP(H) and three steroid substrates: testosterone, 5β-androstane-3a, 1V-diol, and estradiol-17β. In each case the reaction mechanism of the two enzymes was sequential, and inhibi-tion patterns by-products and dead-end inhibitors were consisted with an ordered bi bi mechanism with the coenzyme binding to the free enzyme, although there was difference in affinity and maximum velocity for the steroidal substrates between the two enzymes. Binding studies of the coenzyme and substrate indicate the binding of coenzyme to the free enzyme, in which 1 mol of NADPH binds to 1 mol of each monomeric enzyme. The 4-pro-R-hydrogen atom of NADPH was transferred to the a-face of the steroid molecule by the two enzymes.抄録全体を表示PDF形式でダウンロード (592K) -
Akira TSUGITA, Toyoaki UCHIDA, H. Werner MEWES, Tatsuaki ATAKA1987 年 102 巻 6 号 p. 1593-1597
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA new method for the acid hydrolysis of protein is presented. Peptide bonds are cleaved by the action of an HC1/trifluoroacetic acid (TFA) vapor mixture. Contamination for the hydrolysis mixture is reduced to low levels (1-3 pmol). Re-covery of hydrophobic amino acid is improved. Short reaction times are achieved and rapid removal of acids is facilitated. The reaction temperature is 158°C for reaction times of 22.5 and 45 min with 7 M HCl and 10% TFA containing 0.1 % phenol.抄録全体を表示PDF形式でダウンロード (324K) -
Shunichi KAMETANI, Yutaka HASHIMOTO, Toshikazu YAMANOUCHI, Yasuo AKANU ...1987 年 102 巻 6 号 p. 1599-1607
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA stable amount, approximately 60 μg, of 1, 5-anhydro-o-glucitol (AG) was detected in the 24-h-urine of normal young rats fed ad libitum. Upon administration of streptozotocin (STZ), this amount was temporarily elevated to as much as 1.1 mg and AG was concomitantly removed from the circulation. The plasma AG level stayed almost null thereafter while the acutely elevated urinary AG excretion de-clined within 24 h to another stable excretion level that was three times as high as that of the untreated rats. In contrast, glucosuria developed much more slowly in the drug-treated rats. Normal rats and mice retained exogenous [14C] A G to a considerable extent and the radioactivity was distributed all over the body. Only a marginal fraction of the radioactivity was excreted as expired CO2. The radio-activities retained in the body and excreted into the urine were mostly attributed to unmetabolized AG. The observations of AG's metabolic stability and its rela-tively low level of leakage into urine suggested the concept of effective renal AG reabsorption. On the other hand, the rats with STZ-induced diabetes and NOD-mice with spontaneously developed diabetes retained little of the radioactive AG in their bodies; most of the injected radioactivity was recovered in the urine within 24 h. This observation was interpreted as due to reduced renal AG reabsorption in these animals. The concept of reduction in renal AG reabsorption in diabetes could account for the reduced plasma AG level generally observed in human diabetic cases.抄録全体を表示PDF形式でダウンロード (698K) -
Chemical Identification of Lipid Components in the Membranous Form of Rat Liver Alkaline PhosphataseShigenori OGATA, Yukari HAYASHI, Kumiko YASUTAKE, Yukio IKEHARA1987 年 102 巻 6 号 p. 1609-1615
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーMembranous and soluble forms of rat liver alkaline phosphatase were selectively prepared by extracting microsomes with n-butanol at pH 8.5 and 5.5, respectively, and purified in homogeneous forms by the method previously established (Miki et al. (1986) Eur. J. Biochem. 160, 41-48). When subjected to polyacrylamide gel electrophoresis, the two forms migrated to the same position in the presence of sodium dodecyl sulfate, while the membranous form remained at the top of gels in the absence of the detergent. Treatment of the membranous form with phospha-tidylinositol-specific phospholipase C resulted in its conversion to a soluble form with the same electrophoretic mobility even in the absence of the detergent as that of the soluble form extracted at pH 5.5. Automated Edman degradation analysis showed that the two forms have the same N-terminal amino acid sequence up to the 30th residue determined. Chemical analyses of hydrolysates of the two forms by gas-liquid chromatography demonstrated that the membranous form contains palmitic acid, stearic acid, and inositol, while the soluble form contains inositol but is devoid of the fatty acids. Taken together, these results suggest that rat liver alkaline phosphatase is covalently attached to phosphatidylinositol acylated with palmitic acid and stearic acid, which functions as the membrane-anchoring domain of the enzyme molecule.抄録全体を表示PDF形式でダウンロード (1153K)
- |<
- <
- 1
- >
- >|