巻号一覧
95 巻, 2 号
選択された号の論文の39件中1～39を表示しています
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Osamu ASAMI, Toshikazu NAKAMURA, Tetsuo MURA, Akira ICHIHARA1984 年 95 巻 2 号 p. 299-309
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーAdult rat hepatocytes in primary culture cannot survive more than 2 days in the absence of calf serum. An extract of bovine pituitary gland had a similar effect to calf serum on the survival of hepatocytes, but its specific activity was 70 times that of calf serum. The survival factor was purified from bovine pituitary gland, and obtained in a homogeneous state judging by sodium dodecylsulfate-polyacrylamide gel electrophoresis and high performance liquid chromatography. Its purification was achieved by acid extraction of the pituitary gland, gel filtrations on Sephadex G-75 and Ultrogel AcA 202, ion-exchanger chromatography on CM-cellulose, and then reverse phase high performance liquid chromatography. The purified factor was effective at 10 ng/ml and maximally effective at 100 ng/ml. The overall recovery of its activity was 30%, and the specific activity of the purified factor was 3, 100 times that in the acid extract. The molecular weight (Mr 8, 000), estimated by Sephadex G-200 filtration, and the strong basic character (pI 10.5) of the purified survival factor suggested that it may be the trypsin inhibitor found in various tissues. Indeed, the amino acid composition of the pure material was identical with that of bovine pancreatic trypsin inhibitor (bPTI). The purified survival factor had the same inhibitory activity on trypsin as commercial bPTI and, conversely, commercial bPTI greatly enhanced survival of rat hepatocytes. Thus, the survival factor in bovine pituitary gland was identified as bPTI.抄録全体を表示PDF形式でダウンロード (2245K) -
XIII. Properties of 2, 4-Dienoyl-CoA Reductase from Beef LiverMichinao MIZUGAKI, Chiharu KIMURA, Akira KONDO, Akihiko KAWAGUCHI, Shi ...1984 年 95 巻 2 号 p. 311-317
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーIt is demonstrated that 3-alkenoyl-CoA is the product of the enzymic reduction catalyzed by 2, 4-dienoyl-CoA reductase with the highly purified enzyme preparation from beef liver mitochondria.
Incorporation of deuterium atoms from deuterium-labeled NADPH and 2H2O during the reaction catalyzed by 2, 4-dienoyl-CoA reductase from beef liver was investigated. When trans-2, trans-4-decadienoyl-CoA was incubated with the reductase in the presence of 4R-[4-2H1] NADPH and H2O, no deuterium was detected in the reaction product by gas chromatography-mass spectrometry after derivatization to pyrrolidine amides of fatty acids. When the substrate was incubated with the enzyme in the presence of 4S-[4-2H1] NADPH and H2O, one deuterium atom was incorporated into the product, 3-decenoate, at the C-5 position. In the case of 3-decenoate enzymatically prepared in the presence of NADPH and 2H2O, two deuterium atoms were incorporated into the product at the C-2 position. These results indicate that the reaction catalyzed by 2, 4-dienoyl-CoA reductase from beef liver is a unique example of 1, 4-addition of hydrogen to a 1, 3-diene system conjugated with a carbonyl group of a thioester in biochemical fields.
Chain length specificity of the reductase, isotope effects on reaction rates and competitive inhibitors are also discussed.抄録全体を表示PDF形式でダウンロード (601K) -
Setsuro FUJII, Toru YOKOYAMA, Koji IKEGAYA, Nobuo YOKOO1984 年 95 巻 2 号 p. 319-322
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリー4-Substituted carbonylphenyl ester derivatives were prepared and their inhibitory effects on chymotrypsin, trypsin, thrombin, plasmin, pancreatic kallikrein, and plasma kallikrein were examined. Among the various inhibitors tested, 4- [2-(dimethylamino) ethylaminocarbonyl] phenyl 1, 2, 3, 4-tetrahydro-l-naphthoate hydrochloride (FK-316), 4- [(2-[4-pyrrolidinocarbonylmethyl)piperadino] ethyl) oxycarbonyl]-phenyl 5-methoxyindole-3-acetate dihydrochloride (FK-375), 4- [(2-[4-(piperidinocar-bonylmethyl)piperadino]ethyl) oxycarbonyl] phenyl 1-naphthylacetate dihydrochloride (FK-386), 4- [(2-[4-(2-[morpholino] ethyl) piperadino] ethyl) oxycarbonyl] phenyl 5-methoxy-2-methylindole-3-acetate trihydrochloride (FK-401) and 4- (4-isopropylpiperadinocarbonyl) phenyl 1, 2, 3, 4-tetrahydro-l-naphthoate methanesulfonate (FK-448) were the most effective and specific inhibitors of chymotrypsin.抄録全体を表示PDF形式でダウンロード (277K) -
James L. PIPKIN, Jeanne F. ANSON, William G. HINSON, Henry SCHOL, Dani ...1984 年 95 巻 2 号 p. 323-333
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe effect of isoproterenol (IPR) on phosphorylation of acidic nuclear proteins was investigated by two-dimensional gel autoradiography. Mouse spleen cells stimulated to divide by the mitogen concanavalin A (Con A) were separated according to cell cycle stage by flow microfluorometric technique.
Exposure of cells for 48h to 4 μg IPR/ml culture medium produced no significant change in the proportion of S and G2 phase cells, while a cumulative dose of 8 μg IPR/ml caused a significant repression in DNA synthesis and a reduction in the number of nuclei in G2+ M phase. Four pig IPR/ml stimulated the greatest amount of G0+Gl phosphorylation of nuclear protein. Several proteins from G0+G1 and S nuclei incorporated 32P after Con A+IPR administration, and one protein from S phase nuclei revealed intensified labeling at the 8 μg cumulative IPR dose but not at the 4 μg dose. The isolated proteins (W, X, Y, and Z) were reassociated with homologous DNA, centrifuged in a sucrose gradient and shown to co-sediment with DNA. S phase nuclear protein X-S, which was found to be a mixture of proteins (X0 and X1), was the only exception. One component of X-S, X0 bound to DNA, while component X1 failed to bind. Chyrnotryptic and V8 protease digests of all isolated proteins were made and analyzed by autoradiography. Proteins X0 and X1, recovered from the sucrose gradient, possessed dissimilar fragment patterns. It is concluded that protein X-S is composed of two proteins (X0 and X1), one of which (X1) appears during S phase during the 8 μg IPR induced nuclear repression.抄録全体を表示PDF形式でダウンロード (3214K) -
Hiroko ISHII-OHBA, Reiko MATSUMURA, Hiroshi INANO, Bun-ichi TAMAOKI1984 年 95 巻 2 号 p. 335-343
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーCytochrome b5 was purified from porcine testicular microsomes, and its amino acid composition was determined. Rabbit antibody against the purified cytochrome b5 was prepared in order to study the contribution of cytochrome b5 to testicular microsomal oxygenases related to androgen production.
In the presence of NADPH alone as the electron donor, the antibody against cytochrome b5 inhibited the activities of steroid 17α-hydroxylase and C-17-C-20 lyase of rat testicular microsomal fraction. Addition of NADH to the NADPH-supported oxygenase assay system enhanced both steroid oxygenase activities, and addition of the antibody against cytochrome b5 decreased the NADH-caused stimulation of steroid 17α-hydroxylase and C-17-C-20 lyase activities.
When dehydroepiandrosterone and NAD+ were added as substrates for 3β-hydroxy-_??_5-steroid dehydrogenase in order to synthesize NADH by enzymatic reaction, the NADPH-supported activities of steroid 17α-hydroxylase and C-17-C-20 lyase were further stimulated as compared with the addition of NADH, and this stimulation was suppressed by the antibody against cytochrome b5.
These results suggest that cytochrome b5, together with 3β-hydroxy-Δ5-steroid dehydrogenase, contributes to the activities of steroid 17α-hydroxylase and C-17-C-20 lyase in the testicular microsomal fraction.抄録全体を表示PDF形式でダウンロード (1358K) -
Hideyu ONO, Akio ITO1984 年 95 巻 2 号 p. 345-352
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーSulfite oxidase, a soluble enzyme in mitochondrial intermembrane space, was synthesized as a precursor protein larger than the authentic mature enzyme when rat liver total RNA was translated in a cell-free system. When the in vitro translation products were incubated with isolated rat liver mitochondria, pre-sulfite oxidase was recovered in mitochondria and converted to the size of the mature enzyme. The in vitro-processed mature enzyme was recovered in the intermembrane space of mitochondria (Ono, H. & Ito, A. (1981) Biochenr. Biophys. Res. Commun. 107, 258-264). Mature sulfite oxidase was not imported into mitochondria, and did not affect the import of pre-sulfite oxidase.
When mitochondria were incubated with gel-filtered translation products, the import was dependent on ATP, and the activity restored by the addition of ATP was blocked by valinomycin and K+ ion. These results suggest that the import of pre-sulfite oxidase into mitochondrial intermembrane space requires an electrochemical potential across the inner membrane.
When mitochondria were fractionated, most of the processing activity was recovered in the mitoplast, whereas the inner membrane (after being mostly inverted by sonication) exhibited only slight activity. The processing activity was strongly inhibited by some metal chelators including EDTA, GTP, and Zincon. It was not inhibited by phenyl methyl sulfonyl fluoride, aprotinin, or various microbial protease inhibitors including pepstatin, antipain, leupeptin, and chymostatin. The processing enzyme seems to be a metal protease. The processing of pre-sulfite oxidase by mitoplasts was energy-dependent.抄録全体を表示PDF形式でダウンロード (4281K) -
Hideyu ONO, Akio ITO1984 年 95 巻 2 号 p. 353-358
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーRat liver mitochondria were incubated with in vitro translation products programmed by liver RNA, then disrupted by sonication and subjected to sucrose density gradient centrifugation. Pre-sulfite oxidase bound preferentially to the outer mitochondrial membrane recovered with the inner membrane. This outer membrane could not be separated from the inner membrane by recentrifugation, suggesting the tight association of both membranes. The binding was not affected by pretreatment of mitochondria with proteolytic enzymes.
The mature enzyme and its precursor synthesized in isolated hepatocytes have isoelectric points of 4.2 and 5.5, respectively. The molecular size of the precursor in cytosol was estimated to be about 100, 000 daltons (dimer) by gel filtration.抄録全体を表示PDF形式でダウンロード (2482K) -
Yoshihiro FUKUSHIMA, Shimpei YAMADA, Makoto NAKAO1984 年 95 巻 2 号 p. 359-368
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーIn order to characterize low affinity ATP-binding sites of renal (Na+, K+) ATPase and sarcoplasmic reticulum (Ca2+) ATPase, the effects of ATP on the splitting of the K--sensitive phosphoenzyrnes were compared. ATP inactivated the dephosphorylation in the case of (Na+, K+) ATPase at relatively high concentrations, while activating it in the case of (Ca2+) ATPase. When various nucleotides were tested in place of ATP, inactivators of (Na+, K+) ATPase were found to be activators in (Ca2+)ATPase, with a few exceptions. In the absence of Mg2+, the half-maximum concentration of ATP for the inhibition or for the activation was about 0.35mM or 0.25mM, respectively. These values are comparable to the previously reported Km or the dissociation constant of the low affinity ATP site estimated from the steady-state kinetics of the stimulation of ATP hydrolysis or from binding measurements. By increasing the concentration of Mg2+, but not Na+, the effect of ATP on the phosphoenzyme of (Na+, K+) ATPase was reduced. On the other hand, Mg2- did not modify the effect of ATP on the phosphoenzyme of (Ca2+) ATPase. During (Na+, K+) ATPase turnover, the low affinity ATP site appeared to be exposed in the phosphorylated form of the enzyme, but the magnesium-complexed ATP interacted poorly with the reactive K+-sensitive phosphoenzyme, which has a tightly bound magnesium, probably because of interaction between the divalent cations. In the presence of physiological levels of Mg2+ and K+, ATP appeared to bind to the (Na+, K+) ATPase only after the dephosphorylation, while it binds to the (Ca2+) ATPase before the dephosphorylation to activate the turnover.抄録全体を表示PDF形式でダウンロード (846K) -
Takao YORA, Yoshikatsu SAKAGISHI, Yohtalou TASHIMA, Masayoshi KUMEGAWA1984 年 95 巻 2 号 p. 369-376
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe induction of alkaline phosphatase (ALP) by dibutyryl adenosine 3':5'-cyclic monophosphate (Bt2cAMP) was investigated in strain JTC-12•3 cells derived from monkey (Maccaca irus) kidney cortex. ALP activity was increased by Bt2cAMP in a dose-dependent manner, reaching a plateau at concentrations higher than 5mM with the activity being about 4 times that of the controls. The concentration of Bt2cAMP required for half-maximal induction of ALP activity was about 0.8mM. ALP activity was increased rapidly by Bt2cAMP for the first 5 days and then continued to increase gradually towards a plateau level. Removal of Bt2cAMP from the medium caused a rapid decrease in the activity, suggesting that the induction of ALP activity by Bt2cAMP is reversible. ALP activity was induced synergistically in the presence of 1mM sodium butyrate together with Bt2CAMP at concentrations from 0.01 to 1mM. It was also found that in the presence of 1mM Bt2cAMP, sodium butyrate increased ALP activity in the same manner as Bt2cAMP did in the presence of 1mM sodium butyrate. Although dexamethasone, a potent glucocorticoid, had no effect on ALP activity in control cells, the hormone suppressed the ALP activity induced by Bt2cAMP in a dose-dependent manner. At concentrations above 0.2mM, two xanthine derivatives, theophylline and 3-isobutyl-1-methyl-xanthine (IBMX), also inhibited the induction of ALP activity by 1mM Bt2cAMP. Inhibitors of protein synthesis, cycloheximide (1.5 μg/ml) and pactamycin (10 μg/ml), as well as inhibitors of RNA synthesis, actinomycin D (2 μg/ml) and α-amanitin (50 μg/ml), suppressed the induction of ALP activity. Hydroxyurea markedly enhanced the induction of ALP activity by 1mM Bt2cAMP in the range of dosages examined (5 to 80 μg/ml), while it did not cause any change in ALP activity in control cells. 5-Bromodeoxyuridine (BrdU) did not affect the level of ALP activity in control cells or in cells treated with I mNt Bt2cAMP. Thus, the level of ALP activity in JTC-12•3 cells was found to be influenced by several agents such as Bt2cAMP, sodium butyrate, dexamethasone, xanthine derivatives, and hydroxyurea.抄録全体を表示PDF形式でダウンロード (672K) -
Shohei MAEKAWA, Eisuke NISHIDA, Yasutaka OHTA, Hikoichi SAKAI1984 年 95 巻 2 号 p. 377-385
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThree new actin-binding proteins having molecular weights of 26, 000, 21, 000, and 19, 000 were isolated from porcine brain by DNase I affinity column chromatography. These proteins were released from the DNase I column by elution with a solution of high ionic strength. They were further purified by column chromatographies using hydroxyapatite, phosphocellulose, and Sephadex G-75. All of these actin-binding proteins behaved as monomeric particles in the gel filtration chromatography. After elution of the three actin-binding proteins, actin and profilin were recovered from the DNase I column with 2M urea solution. The eluted actin was further purified by a cycle of polymerization and depolymerization and finally by gel filtration. Little difference in polymerizability was detected between the purified brain actin and muscle actin. After sedimentation of the polymerized brain actin, profilin was purified by DEAE-cellulose and gel filtration column chromatographies. In the assay of the action of these actin-binding proteins, the 26K protein was found to cause a large decrease in the rate of actin polymerization, while showing little effect on the extent of polymerization. The 21K protein decreased the steady-state viscosity of actin solution in a concentration-dependent manner irrespective of whether it was added before or after actin polymerization. It reacted with actin at a 1:1 molar ratio.抄録全体を表示PDF形式でダウンロード (2679K) -
Eisuke NISHIDA, Shohei MAEKAWA, Eiro MUNEYUKI, Hikoichi SAKAI1984 年 95 巻 2 号 p. 387-398
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA 19K protein isolated from porcine brain not only inhibits actin polymerization but depolymerizes actin filaments quickly. The protein reacts stoichiometrically with actin in a 1:1 molar ratio. When actin is induced to polymerize with salts in the presence of the brain 19K protein, the lag phase is prolonged, and the extent of polymerization is decreased, but the half-polymerization time is not increased. This can be explained by assuming that the 19K protein severs growing actin filaments and thus causes an increase in the number of filament ends during the polymerization process, thereby accelerating the overall polymerization. Moreover, the low-shear viscosity of actin filaments is reduced much more than the high-shear viscosity by the 19K protein, suggesting that actin filaments become shorter in the presence of the 19K protein than in its absence. Actin filament depolymerization by the 19K protein is much faster than that by brain profilin or than spontaneous depolymerization. This indicates that the 19K protein depolymerizes actin filaments not only by sequestering actin monomers but also by directly attacking the filaments. The number of actin filaments, measured by assaying the nucleating ability, is increased by substoichiometric concentrations of the 19K protein, irrespective of whether the protein is added to actin monomers before polymerization or added to preformed actin filaments. These results suggest that the brain 19K protein not only stabilizes actin monomers but also cuts actin filaments, thereby decreasing the extent of actin polymerization and also changing the filament length. The action on actin of the actin-depolymerizing protein from starfish oocytes resembles that of the brain 19K protein, although the molecular weight of the starfish protein is slightly smaller. The brain 19K protein and starfish protein should be classified into a new functional group of actin-binding proteins.抄録全体を表示PDF形式でダウンロード (2196K) -
Eisuke NISHIDA, Shohei MAEKAWA, Hikoichi SAKAI1984 年 95 巻 2 号 p. 399-404
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーWhen porcine brain actin is polymerized in either KCl/MgCl2 or KCl alone, porcine brain profilin prolongs the lag phase and inhibits the rate and extent of polymerization in a concentration-dependent manner. Profilin also decreases the elongation rate in a concentration-dependent manner. Moreover, addition of profilin to steadystate actin filaments causes slow depolymerization. All these actions of profilin are explainable by a monomer sequestering mechanism. The inhibition by profilin of both the extent of polymerization and the elongation rate is stronger in KCl alone than in KCl/MgCl2. Moreover, it was found that brain profilin inhibits the polymerization of brain actin more strongly than that of muscle actin. Brain 88K protein/actin complex (88K/A), which has been shown to cap the barbed end of actin filaments, potentiates the inhibitory action of profilin; i.e. the extent of polymerization is much more reduced by profilin in the presence of 88K/A than in its absence.抄録全体を表示PDF形式でダウンロード (514K) -
Shinkichi IRIS1984 年 95 巻 2 号 p. 405-412
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーChick liver xanthine dehydrogenase was highly purified by preparative polyacrylamide gel electrophoresis at the final step of purification, which allowed removal of another contaminating, xanthine-oxidizing enzyme showing a molecular mass of about 380K daltons. Purified XDH showed a specific activity higher than 2, 500 units per mg of protein. On treatment with sodium dodecyl sulfate and 2-mercaptoethanol, XDH was split into two subunits (named as a and β) of different size in an equimolar ratio. The molecular weights of these subunits were estimated as 155K for a and 135K for β. In the form of sodium dodecyl sulfate-complex, subunit α tended to degrade into smaller peptides, whereas subunit β was relatively stable.抄録全体を表示PDF形式でダウンロード (2551K) -
M. SUBRAMANIAN, B. S. SHESHADRI, M. P. VENKATAPPA1984 年 95 巻 2 号 p. 413-421
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーBinding of lysozyme with cetyltrimethylammonium bromide (CTAB) and dodecyl-trimethylammonium bromide (DTAB) at various detergent concentrations and pH was studied at 25°C by equilibrium dialysis technique. In the case of CTAB, binding isotherms at pH 5.0, 7.0, and 9.0 show cooperative binding at all the concentrations of the detergent and the binding ratios increase with pH. Cooperative binding is also shown by DTAB at all the concentrations and pH, but the binding ratios are lower compared to CTAB. The Gibb's free energy change calculated on the basis of Wyman's binding potential concept increases with pH, indicating increased binding strength of CTAB at higher pH.
The UV difference spectra of CTAB and DTAB with lysozyme and its model compounds such as L-Trp, L-Tyr•HCI and L-Phe show two peaks at 297 nm and 250 nm at pH 9.0 indicating the possible involvement of tryptophans as the binding sites along with the carboxylate anion or the phenolic group of a tyrosine on lysozyme. The effect of higher ionic strength on the binding of CTAB with lysozyme at pH 9.0 is evidenced by lower binding ratios and decreased intensities of the UV difference bands, thus indicating the involvement of electrostatic interactions. However, the hydrophobic interactions between the detergents and the aromatic amino acid residues in lysozyme contribute more to the binding strength.
The binding of these cationic detergents by lysozyme induces conformational changes in the enzyme. They are followed by the circular dichroism (CD) technique which shows a decrease in the aromatic bands in the 320-250 nm region. In the 250-200 nm region, the [θ]222 values obtained at various concentrations of CTAB in the complex indicate an increase in the α-helical content indicating a more ordered structure. The CD spectra of lysozyme-DTAB complex were found to be very similar to those of CTAB complex, but the effect was less pronounced probably due to the decrease in the hydrocarbon chain length.
Therefore, it is concluded that hydrophobic interactions play an important role in the detergent binding, whereas electrostatic interactions play only a minor role.抄録全体を表示PDF形式でダウンロード (752K) -
Kyoko MAKIGUCHI, Yoshiko CHIDA, Michiteru YOSHIDA, Kensuke SHIMURA1984 年 95 巻 2 号 p. 423-429
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーIn the previous studies with endonucleases specific for single-stranded DNA, we have indicated that the nonhistone chromosomal protein HMG (1+2) prepared from pig thymus has an activity to unwind DNA partially at low protein-to-DNA weight ratios (Yoshida, M. & Shimura, K. (1984) J. Biochem. 95, 117-124). In the present work, we have pursued the unwinding reaction by HMG (1+2) by thermal melting temperature analysis of DNA, and by investigating the effect of Mg2+ on the reaction. The melting temperature of DNA in the presence of HMG (1+2) at low protein weight ratios decreased in 2mM Tris-HCI, pH 7.8, whereas it increased at higher ratios. The depressions of melting temperature by HMG (l+2) at low ratios were not observed either in the system of 2mM Tris-HCl, pH 7.8, containing EDTA or in the system containing samples treated in advance with EDTA. An addition of Mg2+ to the system reproduced the depression of melting temperature at low protein-to-DNA ratios as well as the increase at higher ratios. Analysis by Mg2+-equilibrated gel filtration revealed that HMG (1+2) is a Mg2+-binding protein. However, the depression of melting temperature at low protein-to-DNA ratios was not due to removal of Mg2+ from DNA by HMG (1+2). From these results, it is concluded that HMG (1+2) causes a partial DNA unwinding detectable by thermal melting temperature analysis of DNA, and that Mg2+ is necessary for the unwinding reaction.抄録全体を表示PDF形式でダウンロード (560K) -
Hideyuki MATSUDA, Nozomu NISHI, Keiko TSUJI, Koichiro TANAKA, Tomisabu ...1984 年 95 巻 2 号 p. 431-442
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーIt was previously reported that in chromatophores of Rhodospirillurn rubrum, reaction center, which consists of three kinds of protein (Mm, about 78K), is a small fragment of a large protein complex (PRU; photoreaction unit), which contains six other kinds of protein including light-harvesting bacteriochlorophyll protein, has Mm of about 700K and is free of phospholipid [J. Biochem. 86, 1211-1224 (1979); 94, 1815-1826 (1983)]. In the present study, the photosynthetic, cyclic electron transport system sensitive to antimycin A was effectively reconstructed by incubating 60 nM PRU (which contained 1 mol of reaction center and 2 mol of ubiquinone-10 per mol) with 300 nM each of oxidized ubiquinone-10 protein, reduced cytochrome c2 and lipoamino acid (which were all purified from Rhodospirillurn rubrum) in the presence of low concentrations of cholate and deoxycholate (pH 8.0). In the light, the cytochrome was oxidized while the quinone was reduced. The oxidation and reduction each progressed rapidly at first, then slowly, reaching maxima (steady states) 1-2min after the light had been turned on. At the steady states, 30% of the cytochrome was oxidized while 11 of the total quinone was reduced. When the light was turned off, the original oxidation-reduction states of the cytochrome and quinone were restored at rapid rates initially then at slow rates. Antimycin A stimulated the slow rates in the light-on state and depressed them in the light-off state, but did not influence the fast rates. Ubiquinone-10 protein was required for the antibiotic-sensitive, slow oxidation reactions. This indicates that the slow rates were due to cyclic electron transport. Cytochrome c2 was tightly bound to PRU at a molar ratio of 1:1. This cytochrorne as well as the quinone bound to PRU was responsible for the fast rates. PRU had other sites able to bind cytochrome c2 and ubiquinone-10 protein with Km of 0.4 and 0.1 μM, respectively. Of the polar lipids tested, lipoarnino acid was the most effective for reconstruction, and its effect was maximal at 300 nM, which is far below its critical micelle concentration.抄録全体を表示PDF形式でダウンロード (946K) -
Michio YAZAWA, Eriko KAWAMURA, Osamu MINOWA, Koichi YAGI, Mitsuhiko IK ...1984 年 95 巻 2 号 p. 443-446
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA single cysteine residue (Cys-27) of wheat calmodulin was labeled with 13C by cyanylation. No change in the Ca2+ saturation pattern was observed after the cyanylation. On titration which Ca2+, the chemical shift of the 13C-label showed a downfield shift. The downfield shift was observed at Ca2+/calmodulin molar ratios between 1.8 and 3.5, while a blue shift of the UV absorption of Tyr-139 was observed between 0 and 1.7. The result indicated the domain 1 containing Cys-27 to be the low affinity site for Ca2+.抄録全体を表示PDF形式でダウンロード (287K) -
Tsuyoshi KATOH, Sadahiro IMAE, Fumi MORITA1984 年 95 巻 2 号 p. 447-454
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーCovalent cross-linking reaction between SH1 and SH2 groups in myosin subfragment-1 (S-1) by N, N'-p-phenylenedimaleimide (pPDM) was followed by the degree of inactivation of NH+4-EDTA ATPase activity. The rate of the cross-linking reaction decreased to less than a 20 th in the presence of F-actin. The inhibitory effect of F-actin was not observed in the presence of MgATP.
Binding of F-actin to S-1 was measured using ultracentrifugation. S-1 whose SH1 and SH2 were covalently cross-linked by pPDM or 5, 5'-dithiobis (2-nitrobenzoic acid) (DTNB) did not bind F-actin. After the DTNB-cross-linked S-1 is reduced by dithiothreitol, the ability to bind F-actin is recovered.
These results suggest that S-1 has a binding site for F-actin in the region between SH1 and SH2. This site appears to determine the high affinity of acto-S-1 complex at the rigor while decreasing the affinity more than 102 times in the presence of MgATP.抄録全体を表示PDF形式でダウンロード (622K) -
Yukinobu KATO, Hitoo IWASE, Kyoko HOTTA1984 年 95 巻 2 号 p. 455-463
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーOvalbumin was extracted with a buffered Triton X-100 solution from oviduct slices incubated with [35S] methionine or [2-3H] mannose and was purified by CM-cellulose and Sephacryl S-200 column chromatography. The labeled ovalbumin was fractionated on a concanavalin A (Con A)/Sepharose column at room temperature. Six fractions were separated: Two unadsorbed fractions, OA and OB; and four adsorbed fractions, OC, OD, OE, and OF. Fractions OA, OB, OC, and OD corresponded to the four fractions prepared from unlabeled ovalbumin as previously reported (Iwase, H. et al. (1981) J. Biol. Chem. 256, 5638-5642). Fractions OE and OF were novel constituents of the labeled ovalbumin, although a small amount of OE was also present in unlabeled ovalbumin.
Pulse-chase experiments indicated that both OE and OF behaved as biosynthetic intermediates of the other ovalbumin fractions, namely OA, OB, OC, and OD. Partial structural analyses involving endo-β-N-acetylglucosaminidase treatment and subsequent Bio-Gel P-4 chromatography showed that both OE and OF were composed of components bearing high mannose-type sugar chains which consisted of Man9-GlcNAc2, Man8GlcNAc2, or Man;GlcNAc2. We failed to distinguish OF from OE on the basis of their carbohydrate chains. However, on SDS slab gel electrophoresis, the OF band migrated slower than the OE band.抄録全体を表示PDF形式でダウンロード (1397K) -
Tetsuo MAITA, Shuichi NAGATA, Genji MATSUDA, Shinsaku MARUTA, Kohei OD ...1984 年 95 巻 2 号 p. 465-475
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe acid protease B (SLB) of Scytalidium lignicolum was reduced and carboxymethylated and then subjected to tryptic digestion. Five fragments were isolated and some of them were further digested with α-chymotrypsin, thermolysin, and dilute acetic acid. The sequence analysis of these fragments and the peptides by conventional methods established the complete amino acid sequence of SLB. The enzyme was composed of 204 amino acid residues with threonine and valine as its amino-and carboxyl-termini, respectively. Locations of three disulfide bridges were also established to be Cys47-126, Cys140-163, and Cys192-201 by enzymatic fragmentation of the denatured and unmodified SLB. Only a slight homology was found in the sequences of SLB and other acid proteases hitherto reported.抄録全体を表示PDF形式でダウンロード (786K) -
Kenji YAMAMOTO, Osamu KAMATA, Yuzo KATO1984 年 95 巻 2 号 p. 477-484
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThree forms of cathepsin H-like cysteine proteinase were purified from rat spleen by a method involving acid treatment and chromatography on pepstatin-Sepharose, Sephadex G-75, DEAE-Sephacel, CM-Toyopearl, and concanavalin A-Sepharose. The final preparations of these forms all migrated as single protein bands on polyacrylamide gel electrophoresis with and without sodium dodecyl sulfate (SDS). The molecular weights of the three forms were estimated to be 28, 000 (form I), 26, 000 (form II), and 22, 000 (form III). The optimal pH was 6.5 for forms I and III and was 7.0 for form II with L-leucine 2-naphthylamide (Leu-NA) or with α-N-benzoyl-DL-arginine 2-naphthylamide (BANA). All of the forms consisted of two major species having isoelectric points of 7.1 and 6.5 on isoelectric focusing gels. They were all stable when incubated at pH values between 5.0 and 9.0 for 1h at 22 C. They were strongly inhibited by iodoacetic acid and E-64, but not by metal ions or pepstatin. Form III was not affected by leupeptin, chymostatin, antipain or elastatinal, which gave essentially complete inhibition of cathepsin B purified from rat spleen. Forms I and II were slightly inhibited by these compounds at the same concentrations. The properties of these forms were compared with those of the known enzymes cathepsin H and BANA-hydrolase.抄録全体を表示PDF形式でダウンロード (1092K) -
Katsumi KAWASAKI, Kyosuke NAGATA, Takemi ENOMOTO, Fumio HANAOKA, Masa- ...1984 年 95 巻 2 号 p. 485-493
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA protein factor which stimulates DNA polymerase α activity on heat-denatured DNA has been purified from mouse FM3A cells. The final preparation had a specific activity of 43, 000 units/mg protein and lacked detectable DNA polymerase, RNA polymerase, DNA-dependent- and independent ATPase, exo- and endodeox-yribonuclease and phosphatase activities. The stimulating factor sedimented at 2.9 S in a glycerol gradient. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of the glycerol gradient fraction revealed the presence of a major band of 36, 000 daltons, the amount of which corresponded well with the level of stimulating activity. The stimulation by the factor was specific for heat-denatured DNA, and a little or no stimulation was observed with native DNA, ribo- and deoxyribohomo-polymers and single stranded circular DNA. Alkaline sucrose gradient sedimentation analysis of the reaction products revealed that newly synthesized DNA was covalently linked to the termini of heat-denatured DNA. The average chain length of the elongated span determined by the digestion with micrococcal nuclease and phosphodiesterase II, did not differ between in the presence and absence of the stimulating factor, suggesting that the stimulation by the factor was due to the increase in the initiation frequency of DNA synthesis from the 3'-hydroxyl terminus of heat-denatured DNA.抄録全体を表示PDF形式でダウンロード (1312K) -
Yoshimi TOMITA, Akira FUSE, Takashi MIKI, Tsuguo KUWATA1984 年 95 巻 2 号 p. 495-501
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe anti-viral and anti-cell fusion actions of human γ interferon (IFN) were examined on human rhabdomyosarcoma cells and compared with the actions of IFN-α. Treatment of A 204 and RD114-C1 cells with IFN-γ resulted in significant inhibition of retrovirus production and cell fusions which were induced by Sendai virus, but IFN-γ did not induce 2'-5' oligoadenylate (2-5 A) synthetase or dsRNA-dependent protein kinase, and failed to inhibit EMC virus replication in RD114-C1 cells as previously observed on IFN-α treatment (Tomita, Y. et al. (1982) Virology 120, 258-263). Although IFN-γ induced 56 K protein more strongly than IFN-γ in human transformed HEp-2, HeLa, RSa, IFr, and A 204 cells, no significant induction of this protein was observed in RD114-C1 cells after IFN-γ or IFN-γ treatment. Specific bindings of 125I-labeled human IFN-αA to HeLa, A 204 and RD114-C1 cell surfaces showed that the numbers of the binding sites on RD114-C1 cells were reduced to less than 22% of those on A 204 cells. These results suggest that RD114-C1 cells exhibit a reduced number of receptors for IFN on the cell surface and that the receptors are functional for the expression of the anti-retrovirus and anti-cell fusion actions of IFN, but are not enough in number for expression of the anti-EMC virus action of IFN.抄録全体を表示PDF形式でダウンロード (1685K) -
Hidenori YAMADA, Futoshi UOZUMI, Atsuko ISHIKAWA, Taiji IMOTO1984 年 95 巻 2 号 p. 503-510
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーBromoacetamide derivatives having n-alkyl substituents (BrCH2CONH(CH2)nH, 1-n) and carboxyalkyl substituents (BrCH2CONH(CH2)nCOOH, 2-n) react with His-15 in lysozyme exclusively at Nε2 at pH 5.5 and 40°C. Kinetic studies suggest that lysozyme has a small hydrophobic pocket that binds these reagents in the vicinity of His-15.抄録全体を表示PDF形式でダウンロード (569K) -
Kei MARUYAMA, Takashi MIKAWA, Setsuro EBASHI1984 年 95 巻 2 号 p. 511-519
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA new simple method of detecting calcium binding proteins in a protein mixture is described. A sample which might include calcium binding proteins was subjected to SDS-polyacrylamide gel electrophoresis and then electrophoretically transferred to a nitrocellulose membrane. The membrane was then incubated with 45Ca to detect calcium binding proteins as radioactive bands by autoradiography.
Purified troponin-C, calmodulin, myosin DTNB light chain, and parvalbumin were clearly identified by this method. In the whole homogenate of chicken skeletal muscle, myosin DTNB light chain, troponin-C, and 55 K calcium binding protein were found to be radioactive. In the frog skeletal muscle, small molecular weight proteins of approximately 13-15 K and 70 K protein appeared to be the calcium binding proteins. In the case of the carp skeletal muscle, small molecular weight proteins including parvalbumin and two proteins of about 80 K seemed to bind calcium ion. Two high molecular weight calcium binding proteins were present in the scallop striated muscle.
The procedure described can be completed within 24 h and can detect as little as 2 μg of calcium binding protein in the starting sample. Under appropriate conditions it was possible to detect only high affinity calcium binding proteins.抄録全体を表示PDF形式でダウンロード (3915K) -
Takeshi WATANABE, Shin-ichi OKUDA, Hajime TAKAHASHI1984 年 95 巻 2 号 p. 521-527
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe particulate enzyme prepared from Selenomonas ruminantium subsp. lactilytica catalyzed the formation of phosphatidylserine (PS) from CDP-diglyceride and serine, and phosphatidylethanolamine (PE) from PS. This indicates that PS and PE in this organism are synthesized through a similar pathway to that in Escherichia coli.
In turn-over experiments with [32P] orthophosphate and [14C] caproate, a rapid turn-over of PE was observed, while ethanolamine plasmalogen was relatively stable. The decrease of 14C-radioactivity in PE side-chains was accompanied by an increase of 14C-radioactivity in side-chains of ethanolamine plasmalogen. In pulse labelchase experiments with [32P] orthophosphate, significant amounts of 32P-radioactivities were incorporated into plasmalogens at the beginning of the chase and a precursor product relationship was observed between serine plasmalogen and ethanolamine plasmalogen. On the contrary, in pulse-label-chase experiments using [14C] caproate and [3H] glycerol, no significant radioactivity was incorporated into plasmalogens at the beginning of the chase and radioactivities in plasmalogens slowly increased during the chase. These results indicate that 1-O-alk-1'-enyl-2-acyl-glycerol moieties of plasmalogens are derived from a large precursor pool, but the phosphorous moiety is not. This concept was supported by the fact that synthesis of plasmalogens occurred in the absence of fatty acid synthesis.
We wish to propose the possibility that 1-O-alk-1'-enyl-2-acyl-glycerol moieties of plasmalogens are derived from the diglyceride moieties of diacyl phospholipids.抄録全体を表示PDF形式でダウンロード (588K) -
Keiko KITAGISHI, Keitaro HIROMI1984 年 95 巻 2 号 p. 529-534
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーEquilibrium and kinetic studies on the interaction between thermolysin (E) and its specific inhibitor (I), phosphoramidon (N-(α-L-rhamnopyranosyloxyphospho)-L-leucyl-L-tryptophan), have been made by steady-state inhibitory kinetics analysis, fluorometric titration and the stopped-flow method. The inhibitor constant, K1, the dissociation constant of the EI complex, Kd, directly obtained by fluorometric titration, and the apparent second-order association constant, kon, obtained with the stopped-flow method are very similar to those for talopeptin (Kitagishi, K., et al. (1983) J. Biochem. 93, 47-53 and 55-59), whose molecular structure differs from that of phosphoramidon only in the configuration of the OH group at the C-4 atom of the sugar moiety. The result suggested that the OH group is not essential for the binding to thermolysin.抄録全体を表示PDF形式でダウンロード (403K) -
Kazuo SAKAGUCHI, Ken'ichiro MITSUI, Jun'ichi HASE, Kyoichi KOBASHI1984 年 95 巻 2 号 p. 535-541
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーJack bean urease [EC 3. 5. 1. 5] was modified with diazonium-1H-tetrazole (DHT). Reaction of DHT with the enzyme produced a characteristic absorption peak at 320 nm and led to complete loss of the enzymatic activity at a low concentration of DHT. Amino acid analysis of DHT-modified urease showed that only cysteine residues reacted with the reagent and other amino acid residues such as tyrosine, histidine, and lysine did not. The enzymatic activity was protected against DHT-inactivation by the addition of substrate. On the other hand, when the cysteine residues were modified with DHT, the enzyme was not converted to polymeric forms. Furthermore, the binding ability of urease with hydroxamic acid, a specific urease inhibitor, was virtually unaffected by DHT-inactivation. These results indicate that cysteine residues are specifically modified by DHT with concomitant loss of enzymatic activity and polymerization ability, but are not essential for the binding of hydroxamic acid to the enzyme.抄録全体を表示PDF形式でダウンロード (1289K) -
Yuichi TAKAKUWA, Tohru KANAZAWA1984 年 95 巻 2 号 p. 543-550
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーSarcoplasmic reticulum vesicles were preloaded with either 45Ca2+ or unlabeled Ca2+. 45Ca2+ efflux and influx were determined in the presence and absence of acetylphosphate. Phosphorylation of the membrane-bound (Ca2+, Mg2+)-ATPase by [32P]acetylphosphate was also determined. The rate of efflux with acetylphosphate was considerably higher than that without acetylphosphate. When the acetylphosphate concentration was greatly reduced by diluting the reaction mixture after the start of the reaction, the rate of the efflux decreased markedly. These results demonstrate the acceleration of 45Ca2+ efflux by acetylphosphate. This acetylphosphate-induced efflux required external Ca2+. The external Ca2+ concentration giving half-maximum activation of efflux was 3.8 μM. The Ca2+ concentration dependence of the efflux coincided with that of phosphorylation. When the acetylphosphate concentration was varied, the rate of acetylphosphate-induced efflux changed approximately in proportion to the phosphoenzyme concentration. These and other findings show that acetylphosphate-induced 45Ca2+ efflux represents Ca2+-Ca2- exchange (between the external medium and the internal medium) mediated by the phosphoenzyme and further demonstrate the direct dissociation of Ca2+ from the Ca2+-bound phosphoenzyme to the external medium in Ca2+-Ca2+ exchange.抄録全体を表示PDF形式でダウンロード (630K) -
Hiro-omi MOWRI, Shoshichi NOJIMA, Keizo INOUE1984 年 95 巻 2 号 p. 551-558
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe effect of lipid composition of liposomes on peroxidation induced by ferrous ion and ascorbate was examined. Temperature affects the sensitivity of liposomes; the peroxidation rate was increased with increase of the incubation temperature. With liposomes consisting of 1-palmitoyl-2-arachidonyl phosphatidylcholine (substrate) and a peroxidation-insensitive lipid, 1-palmitoyl-2-oleoyl phosphatidylcholine, peroxidation was dependent on the density of the substrate. No appreciable peroxidation was observed with liposomes containing less than 10 mol% of the substrate at 37°C. When 1 mol substrate was mixed with 9 mol dimyristoyl phosphatidylcholine, peroxidation occurred below 10°C, but not above 20°C. Above 20°C, the substrates should be located homogeneously on the membranes, whereas they should be clustered below 10°C, since the gel-liquid crystalline phase transition temperature of matrix membrane of dimyristoylphosphatidylcholine was 17-21°C. Peroxidation of liposomes consisting of 1-palmitoyl-2-arachidonyl phosphatidylcholine was also suppressed by cholesterol. These findings indicate that the lateral distribution as well as the density of the substrate on membranes affects the sensitivity of the substrate to peroxidation. It was also found that α-tocopherol is preferentially located in the 1-palmitoyl-2-arachidonyl phosphatidylcholine-rich regions of membranes consisting of mixed phospholipids, and efficiently suppresses peroxidation of liposomal lipids.抄録全体を表示PDF形式でダウンロード (606K) -
Tohru YOSHIMURA, Katsuyuki TANIZAWA, Hidehiko TANAKA, Kenji SODA1984 年 95 巻 2 号 p. 559-565
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーL-Lysine: 2-oxoglutarate 6-aminotransferase catalyzes very slow transamination between L-alanine and 2-oxoglutarate. A high concentration of anions such as formate, acetate and halides greatly accelerated this transamination without affecting the affinity of the enzyme for L-alanine. In contrast, the anions strongly inhibited the normal L-lysine 6-transamination in a competitive manner with L-lysine and in a non-competitive manner with 2-oxoglutarate. This result suggests that the enzyme has an anion binding site which normally binds the carboxyl group of L-lysine. The binding of halides or carboxylates to this site probably induces a conformational change of the enzyme, and results in the inhibition of L-lysine 6-transamination, and in the stimulation of L-alanine transamination. Treatment of the enzyme with an arginine-specific dicarbonyl reagent, phenylglyoxal, led to a loss of the enzyme activity for L-lysine. The activity for L-alanine was not affected, but the stimulating effect of anions on L-alanine transamination was impaired. Thus, it is suggested that an arginine residue (s) plays an important role in the anion binding site.抄録全体を表示PDF形式でダウンロード (568K) -
II. Comparison of Diffraction Patterns of Photosynthetic Units from Various Purple BacteriaMikio KATAOKA, Kohji INAI, Tatzuo UEKI, Jinpei YAMASHITA1984 年 95 巻 2 号 p. 567-573
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーComparative X-ray diffraction studies, in conjunction with infrared absorption spectroscopy, were performed on chromatophores isolated from various purple photosynthetic bacteria in order to achieve a better understanding of the molecular structure of the photosynthetic unit. Purple non-sulfur bacteria used were Rhodospirillum rubrum, Rhodospirillum molischianum, Rhodopseudomonas sphaeroides, and Rhodopseudomonas palustris. Chromatophores of Chromatium vinosum, as a typical example of purple sulfur bacteria, were also investigated. The results were as follows.
1. Distinct equatorial X-ray diffraction patterns were obtained from chromatophores of all the bacteria examined. They showed diffuse, continuous diffraction patterns having several maxima, and the patterns are evidently distinguished from those of either crystalline or amorphous material. The pattern indicates that the photosynthetic unit in the chromatophore has a highly organized molecular structure in the plane of the membrane.
2. Bacteria whose major photosynthetic pigment is bacteriochlorophyll α can be categorized in three groups from the viewpoint of near infrared absorption spectra. X-ray diffraction patterns are also grouped accordingly, although the differences are minimal and the patterns display common features. In other words, the bacteriochlorophyll forms, which are bacteriochlorophyll-protein complexes exhibiting different near-infrared absorption spectra, show different X-ray patterns: the molecular structure of photosynthetic units is closely related to the state of pigment in each complex, although the “X-ray” molecular structure is mainly concerned with the arrangement of constituent protein molecules at the present resolution, whereas the “spectroscopic” structure reflects the local environment of pigment.
3. Rhodopseudomonas sphaeroides, Rhodopseudomonas palustris, and Rhodospirillum molischianum show nearly the same features in the near-infrared absorption spectra due to bacteriochlorophyll α. The molecular structures of their photosynthetic units are considered to be the same since they give identical X-ray diffraction patterns. The molecular structure of the photosynthetic units does not depend on the morphological appearance of the photosynthetic apparatus in cells.抄録全体を表示PDF形式でダウンロード (1764K) -
Yuji TSUKAMOTO, Tatzuo UEKI, Mikio KATAOKA, Toshio MITSUI1984 年 95 巻 2 号 p. 575-579
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーPhotosystem I fragments were prepared from thylakoid membranes of a blue-green alga (Anabaena variabilis) and spinach by treatment with a detergent, Triton X-100. Equatorial X-ray diffraction patterns were recorded on films for oriented specimens of thylakoid membranes and photosystem I fragments.
1. The thylakoid membranes and photosystem I fragments gave essentially the same equatorial diffraction patterns in both Anabaena variabilis and spinach, indicating that the major X-ray scatterers in these thylakoid membranes are the molecular assembly of photosystem I.
2. The equatorial X-ray diffraction from the photosystem I fragments of Anabaena variabilis and spinach extends to the reciprocal space of 1/7 Å-1. The diffraction pattern exhibits six to nine distinct maxima though they are diffuse, indicating that the arrangement of the constituent molecules in photosystem I has a definite geometrical regularity. The radial autocorrelation functions indicate that the maximal sizes of photosystem I in these thylakoid membranes are about 100 Å, and the geometrical regularity does not correspond to a crystalline order.
3. The X-ray diffraction patterns from photosystem I fragments from Anabaena variabilis and spinach are quite similar to each other, suggesting the possibility that the molecular structures of photosystem I in Anabaena variabilis and spinach have a fundamental similarity. These diffraction patterns, however, are different from that of the chromatophore obtained from a photosynthetic bacterium, Rhodospirillum rubrum.抄録全体を表示PDF形式でダウンロード (1128K) -
Takahiko ISHIGURO, Mamoru NAKANISHI1984 年 95 巻 2 号 p. 581-583
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA new method has been developed for preparation of supported planar lipid membranes containing transmembrane proteins. Phosphatidylcholine and glycophorin A were deposited on the surface of alkylated glass coverslips by dialysis. The planar lipid membranes prepared in this manner were examined for the binding of wheat germ agglutinin agarose. The binding of the agarose to these membranes is dependent on the membrane fluidity. The advantages of this technique are: (1) a supported planar membrane can be more readily prepared, and (2) less amounts of membrane proteins are needed for reconstitution.抄録全体を表示PDF形式でダウンロード (1019K) -
Takashi OBINATA, Osamu SAITOH, Hiromi TAKANO-OHMURO1984 年 95 巻 2 号 p. 585-588
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe effect of innervation on the transition of tropomyosin, troponin T, and myosin isozyme during chicken breast muscle development was examined by denervating the muscle at various ages after hatching. The types of proteins were characterized by 2-D electrophoresis for tropomyosin, immunoblotting for troponin T and pyrophosphate acrylamide gel electrophoresis for myosin isozymes. As judged by the types of these three proteins, when neonatal muscle was denervated, the protein isoform transition from the neonatal to adult state was interrupted, whereas the denervation of mature muscle caused the reappearance of the neonatal forms of proteins. The present results indicate that differentiation from the neonatal state to the adult state and the maintenance of the adult state are controlled by some factors related to nerves.抄録全体を表示PDF形式でダウンロード (2151K) -
Tadashi MABUCHI, Kazuhiko WAKABAYASHI1984 年 95 巻 2 号 p. 589-592
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA 341 bp sequence from yeast mtDNA was cloned, which consisted of an upstream 98 bp AT stretch and a downstream 206 bp AT stretch separated by a single 37 bp GC cluster. Cleavage of this GC cluster did not cause loss of the autonomously replicating function of this sequence. The recloned first 98 bp AT stretch was incapable of replication, while the recloned 206 bp AT stretch could replicate. We were able to confine an essential sequence for autonomous replication within a 186 bp AT stretch. Sequencing data revealed a sequence of ATATAAAT and stem and loop structures within the AT stretch.抄録全体を表示PDF形式でダウンロード (298K) -
Shigeo KOYASU, Akio FUKUDA, Yoshimi OKADA1984 年 95 巻 2 号 p. 593-595
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーAlteration in penicillin-binding patterns during asymmetrical cell division in the cell cycle of Caulobacter crescentus was examined. Most penicillin-binding proteins (PBPs) were turned over slowly, and their penicillin-binding patterns did not alter appreciably during the cell cycle. One of the PBPs, PBP S2 in the soluble fraction, however, was turned over quickly and was detected only in swarmer cells, suggesting that PBP S2 is synthesized in swarmer cells and turned over and/or inactivated in the following stalked cell cycle.抄録全体を表示PDF形式でダウンロード (823K) -
Nobuhisa KINOHARA, Hirofumi USUI, Kazunori YOSHIKAWA, Masao TAKEDA1984 年 95 巻 2 号 p. 597-600
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe rate of dephosphorylation of isolated P-H2B histone by pig heart phosphoprotein phosphatase (Mr=224, 000) and its catalytic subunit (Mr=31, 000) was suppressed more than 95% at low ionic strength when the substrate was integrated into nucleosome core particles. The suppressed rate was increased 13-43-fold by polyamine hydrochlorides and Mg(CH3COO)2 at the optimal ionic strength of 0.2-0.38M. Phosphatase activity toward integrated P-H2B histone was distributed in both rat liver cytosol and nuclear extracts. The phosphatase activities in these fractions showed similar specific activities and were also increased 10-32-fold by 10mM spermine•4HCl.抄録全体を表示PDF形式でダウンロード (348K) -
III. Evidence for a Biantennary StructureHaruki YAMAGUCHI1984 年 95 巻 2 号 p. 601-604
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーPeptidokeratan sulfates were retained by a concanavalin A-Sepharose column and readily eluted with 20mM methyl α-D-mannoside from the column. Linkage region-enriched glycopeptides, prepared by endo-β-galactosidase digestion of the peptidokeratan sulfates, behaved similarly to the peptidokeratan sulfates on the same affinity chromatography. Further, behaviors of both the peptidokeratan sulfates and the linkage region-enriched glycopeptides on pea lectin-Agarose columns were consistent with the results of the chromatography on concanavalin A-Sepharose. These findings confirmed the typical biantennary structure previously suggested for the linkage region on the basis of structural studies of the linkage region-enriched glycopeptides.抄録全体を表示PDF形式でダウンロード (326K)
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