巻号一覧
77 巻, 2 号
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Teruo SAKURAMA, Tohoru NAKAMURA, Jiro KOYAMA1975 年 77 巻 2 号 p. 265-268
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーDisappearance of rabbit IgG and its Fc fragment from the injected sites in skin and also the relationship to reverse passive cutaneous anaphylaxis (RPCA) were studied using guinea pigs. Rabbit IgG and its Fc fragment, trace labeled with 125I, disap-peared from the injected sites with half-lives of 12-14 and 6-7 hr, respectively. The shorter half-life of the Fc fragment explained why its activity to provoke RPCA disappeared more rapidly than that of intact IgG as the sensitization period was prolonged. The ability to provoke RPCA did not seem to influence the persistence of Fc fragment in the sites, since F(ab')2 as well as Fab fragments had the same half-life as Fc fragment.抄録全体を表示PDF形式でダウンロード (307K) -
Koichi SUZUKI, Motoó WATANABE, Kazutomo IMAHORI1975 年 77 巻 2 号 p. 269-279
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーGlyceraldehyde-3-phosphate dehydrogenase [EC 1.2.1.12] was purified from the horseshoe crab, a living fossil, and its properties were examined.
1. The purified enzyme was homogeneous as judged by various tests. The enzyme, like enzymes from other sources, was a tetramer with a subunit molecular weight of 36, 000. The kinetic parameters and pH optimum were also similar to those of other enzymes, though the enzyme was more stable against heat and pH denatura-tions.
2. Analysis of SH groups showed that there were 4 SH groups per subunit, one of which was essential for the enzyme activity and was highly reactive.
3. CD spectra of the enzyme suggested that the enzyme had a very high content of β-structure (ca. 45%).
4. The horseshoe crab enzyme could form a hybrid in vitro with the rabbit muscle enzyme in concentrated salt solution at acidic pH.
5. These results indicate that the enzyme has overall structural similarity to other enzymes and that the enzyme is highly conserved during a long period of evolution. Some discussions on the structure and activity of the horseshoe crab enzyme are made in comparison with the enzymes from other sources.抄録全体を表示PDF形式でダウンロード (1535K) -
Koichi SUZUKI, Osamu SHIHO, Kazutomo IMAHORI1975 年 77 巻 2 号 p. 281-289
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーFructose-diphosphate aldolase [EC 4.1.2.13] was isolated from horseshoe crab (a living fossil) muscle and some molecular and enzymatic properties were examined. The enzyme was a tetramer with a molecular weight of about 160, 000. The enzyme activity was inhibited by reduction with borohydride in the presence of the substrate and was inactivated by carboxypeptidase A [EC 3.4.12.2] digestion. The pH optima for fructose-diphosphate (FDP) and fructose-1-phosphate (FIP) activities were 6.5-8 and 7.5-8.2, respectively. The ratio of FDP/F1P activities was 30 and Km values were 1.7×10-5M and 2.5×10-3M, respectively, for the two substrates. The horse-shoe crab aldolase was classified as class 1, type A, based on the results obtained. Extensive homology in various properties of the enzyme was observed when it was compared with enzymes from other sources, though some differences could be found in the amino acid composition and in the kinetic properties.抄録全体を表示PDF形式でダウンロード (1289K) -
Seiki KURAMITSU, Kiyoshi IKEDA, Kozo HAMAGUCHI1975 年 77 巻 2 号 p. 291-301
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーThe interactions of the substrate analogues, GlcNAc, β-methyl GlcNAc, (GlcNAc)2, and (GlcNAc)3, with turkey egg-white lysozyme [EC 3.2.1.17], in which the Asp 101 of hen lysozyme is replaced by Gly, were studied at various pH values by measur-ing changes in the circular dichroic (CD) band at 295 nm. Results were compared with those for hen egg-white lysozyme. The modes of binding of these substrate analogues to turkey lysozyme were very similar to those to hen lysozyme except for the participation of Asp 101 in hen lysozyme.
The ionization constants of the catalytic carboxyls, Glu 35 and Asp 52, in the turkey lysozyme-(GlcNAc)3 complex were determined by measuring the pH dependence of the CD band at 304 nm, which originates from Trp 108 near the catalytic car-boxyls. The ionization behavior of the catalytic carboxyls of turkey lysozyme in the presence and absence of (GlcNAc)3 was essentially the same as that for hen lyso-zyme.
The pH dependence of the binding constant of (GlcNAc)3 to hen lysozyme was compared with that to turkey lysozyme between pH 2 and 8. The pH dependence of the binding constant for (GlcNAc)3 to turkey lysozyme could be interpreted entirely in terms of perturbation of catalytic carboxyls. In the case of hen lysozyme, it was interpreted in terms of perturbation of the catalytic carboxyls and Asp 101 in the substrate-binding site. The pK values of Asp 101 in hen lysozyme and the hen lysozyme-(GlcNAc)3 complex were 4.5 and 3.4, respectively.
The binding constants of (GlcNAc)3 to lysozyme molecules with different micro-scopic protonation forms, with respect to the catalytic carboxyls, were estimated. The binding constant of lysozyme, in which Asp 52 and Glu 35 are deprotonated, to (GlcNAc)3 was the smallest. The other three species had similar binding constant to (GlcNAc)3.抄録全体を表示PDF形式でダウンロード (771K) -
Shoko OHSHIMA, Mutsuo SEKIGUCHI1975 年 77 巻 2 号 p. 303-311
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーMutants of bacteriophage T4 which exhibit increased sensitivity to ultraviolet radia-tion were isolated and their abilities to induce an enzyme system to excise pyrimidine dimers were examined. Among 16 mutants isolated, 12 mutants were found to be defective in inducing T4 endonuclease V, which catalyzes the formation of dimer-specific breaks in ultraviolet-irradiated DNA. A leaky v mutant, which exhibits intermediate ultraviolet sensitivity, was also isolated; the mutant induces a low level of endonuclease V and excises only a small amount of dimers in vitro. Three other mutants, as well as x and y mutants, were able to induce both T4 endonuclease V and dimer-excision enzyme (5'→3' exonuclease).抄録全体を表示PDF形式でダウンロード (605K) -
Disk Aggregate of Cucumber Green Mottle Mosaic Virus Protein and Its FunctionTakeshi OHNO, Yoshimi OKADA, Yoshiaki NONOMURA, Hideo INOUE1975 年 77 巻 2 号 p. 313-319
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーAlthough it is established that in the assembly of tobacco mosaic virus (TMV) in vitro, a 20 S disk aggregate of protein is essential for the initiation of the reac-tion, there is no agreement as to whether subsequent rod elongation proceeds by the addition of protein subunits or disks.
Cucumber green mottle mosaic virus (CGMMV) is a rod-shaped virus closely related to TMV. It was observed directly by electron microscopy that CGMMV-protein also formed a single- or double-layer disk aggregate under conditions where reconstitution with the protein and TMV-RNA proceeds efficiently. Whichever forms, a single or double layer, a disk aggregate is required for the initiation of reconstitu-tion, but cannot participate in rod elongation.
These results obtained with CGMMV support our model proposed for the mechanism of assembly of TMV and rod-shaped viruses; i.e., the assembly occurs in two steps; disk aggregates of protein are essential only for initiation, and rod elongation proceeds by subsequent addition of subunits.抄録全体を表示PDF形式でダウンロード (2252K) -
Atsushi IKAI1975 年 77 巻 2 号 p. 321-331
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーThe denaturation of porcine low-density lipoprotein (LDL) in aqueous guanidine hydrochloride (GuHCl) was studied by flotation velocity experiments, optical rotatory dispersion and fluorescence spectroscopy. The denaturation of LDL occurred between 2 and 4M GuHCl, where small sigmoidal changes in optical rotation and fluorescence intensity were noted. The hydrated density of the native LDL was 1.036g/cm3 and this remained constant upon denaturation in 4M GuHCl. The slope of the flotation coefficient-solvent density curve was 35% less for denatured LDL than for the native LDL. Since there is no indication of splitting of LDL in 4M GuHCl, it is natural to interpret the result in terms of an increase of the translational frictional coefficient by 50%. The observed changes in optical rotation, fluorescence intensity and flota-tion coefficient in 4M GuHCl were readily reversed and native LDL was recovered after removal of GuHCl by dialysis.
Proteolytic treatment of denatured LDL produced digested LDL which had a hydrated density of 1.0218/cm3 corresponding to the loss of 30% of apo-LDL. The digested LDL behaved like a compact, globular particle in aqueous NaCl solution and in 4M GuHCl. These results can best be interpreted by a model of the LDL particle in which approximately 30% of apo-LDL is exposed to the solvent, such that it can be reversibly denatured by GuHCl and at the same time is easily available to proteolytic enzymes, whereas the rest of apo-LDL is tightly associated with lipids and possibly buried inside the lipid moiety. SDS-polyacrylamide gel electrophoresis of the digested LDL revealed four major peptide fragments with sizes ranging from 70, 000 to 100, 000 daltons. We believe that the method and results described in this paper will have meaningful applications in the study of membrane proteins.抄録全体を表示PDF形式でダウンロード (2726K) -
Separation, Amino Acid Compositions and Contents in MyosinKoichi YAGI, Yoh OKAMOTO, Yoichi YAZAWA1975 年 77 巻 2 号 p. 333-342
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーLow molecular weight components (g1, g2, and g3) were isolated from rabbit skeletal muscle myosin and their amino acid compositions were analyzed. One mole tryptophan was found in g1 and in g2, but none in g3. One mole of acetic acid was found per mole of each g-chain and it was concluded that the N-terminal groups of all three g-chains are acetylated. The minimum molecular weight of the g-chains were estimated from their amino acid compositions. It was estimated by SDS-disc electrophoresis that 1 mole of myosin contained 0.90, 1.7, and 0.63 moles of g1, g2, and g3, respectively. Similar values were obtained with psoas muscle myosin, but in heavy meromyosin prepared from skeletal muscle myosin the content of g2 was much lower, and that of g3 was much higher.抄録全体を表示PDF形式でダウンロード (698K) -
Yuhei MORITA, Shigeo AIBARA, Honami YAMASHITA, Fumio YAGI, Toshihiko S ...1975 年 77 巻 2 号 p. 343-351
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーβl-Amylase [1, 4-α-D-glucan maltohydrolase, EC 3.2.1.2] has been purified from defatted soybean meal by fractional precipitation with ammonium sulfate, ion-exchange chromatography on CM- and DEAE-Sephadex and gel filtration chromatog-raphy on Sephadex G-100. Two different components of β-amylase were crystallized from ammonium sulfate solutions, and the homogeneity of each preparation was confirmed by sedimentation and disc electrophoretic analyses. Both components of soybean β-amylase formed large single crystals (trigonal crystal system) from 40-50% saturated ammonium sulfate solution buffered at pH 5.4 on dialyzing concentrated protein solution in the apparatus of Zeppezauer et al. Preliminary X-ray diffraction data gave a hexagonal lattice with unit cell dimensions α=86.1 A and c=144.4 A. The space group corresponds to P3121 or P3221, and one asymmetric unit contains one molecule of β-amylase, assuming a crystal density of 1.25g/ml and a molecular weight of the enzyme of 60, 000 daltons. In this case, the crystal has a volume of 2.53 A3 per atomic mass unit, and the percentage of protein in the crystal is about 52.抄録全体を表示PDF形式でダウンロード (3160K) -
Hiroshi HATANAKA, Yoko OGAWA, Fujio EGAMI1975 年 77 巻 2 号 p. 353-359
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーAscorbate-2-sulfate sulfohydrolase was purified 184-fold from a crude extract of the liver of Charonia lampas. In all purification steps including phosphocellulose, first and second Sephadex G-150 column chromatographies, the enzyme activity eluted together with arylsulfatase [EC 3.1.6.1] activity, and was separated from glycosul-fatase [EC 3.1.6.3] activity. The nonidentity of ascorbate-2-sulfate sulfohydrolase and glycosulfatase was further confirmed by an isoelectric focussing study. Ascorbate-2-sulfate sulfohydrolase had an isoelectric point, pI, of 4.9, and had maximum activity at pH 4, 0. Its molecular weight was estimated to be about 154.000.抄録全体を表示PDF形式でダウンロード (485K) -
Tsuneo KAMEYAMA, Tokue KATORI, Takamitsu SEKINE1975 年 77 巻 2 号 p. 361-366
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーStudies were carried out to elucidate the nature of biphasic ATP hydrolysis by myosin at low temperature.
1. The rate of ATP splitting decreased sharply at 3-5min after initiation of the reaction below a critical temperature (25° and 30° in the presence of Ca 21 and EDTA, respectively). On the other hand, Mg2+-ATPase [EC 3.6.1.3] did not exhibit such biphasic kinetics.
2. The Arrhenius plot of the second phase of the reaction after the rate transition gave a straight line whether the temperature of assay was above or below the critical one, giving 5.7 kcal/mole as the activation energy of Ca2+-ATPase. However, that of the first phase was 2 kcal/mole, in agreement with the values reported by other investigators. The Arrhenius plots for both phases of EDTA-ATPase showed features similar to those of Ca2+-ATPase.
3. Michaelis constants for the two phases at 8° were also different. In addition, the first phase of EDTA-ATPase was shown to have two different constants, depending on ATP concentration.
4. The profiles of the dependence of ATPase activity on KCl concentration were essentially the same for both phases, while bending of the time curve was scarcely observed above pH 8 for Ca2+-ATPase or at pH 6 for EDTA-ATPase.
5. 2, 4-Dinitrophenol abolished the phase transition for Ca2+-ATPase and EDTA- ATPase, and heat treatment also minimized the transition for the former.抄録全体を表示PDF形式でダウンロード (404K) -
II. Crystallization and General Properties of Yeast AconitaseTakashi SUZUKI, Osamu YAMAZAKI, Kiyoshi NARA, Shun-ichi AKIYAMA, Yoshi ...1975 年 77 巻 2 号 p. 367-372
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーYeast aconitase [citrate (isocitrate) hydro-lyase, EC. 4.2.1.3], inductively formed by Candida iipolytica in the presence of fluoroacetate, was purified approximately 100-fold by Sephadex G-100 gel filtration and DEAE-Sephadex column chromatography, yielding dark-brown needle crystals. The crystalline aconitase was homogeneous as judged by polyacrylamide gel electrophoresis and sedimentation by ultracentrifuga-tion. The enzyme showed maximal activity at pH 8.0 and at 55°. It has an S20, w of 5.03S, a molecular weight of 68, 500 and an isoelectric point of pH 4.2. The presence of 2.10 moles of iron per mole of the enzyme was demonstrated by atomic absorption spectroscopy.抄録全体を表示PDF形式でダウンロード (1974K) -
Kenichi MATSUBARA, Tsunehiro MUKAI1975 年 77 巻 2 号 p. 373-382
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーAbout 20 copies of plasmid λdv are perpetuated per host chromosome in Escherichia coli K12 cells. The mode of DNA replication of this plasmid λdv was studied, using the density-labeling technique followed by banding in CsCl.
It was shown that all the copies of plasmid λdv are potentially capable of repli-cating roughly once a cell generation. Their replication occurs by random, that is a copy of the plasmid is taken out at random for replication from a pool, to which the two replicas resulting from replication are returned.
Chloramphenicol did not inhibit the initiation of a new round of replication of the plasmid molecules, indicating that selection from the replication pool does not require concomitant protein synthesis.抄録全体を表示PDF形式でダウンロード (785K) -
Kazuei IGARASHI, Kazuko TERADA, Yumiko TANGO, Katsuaki KATAKURA, Seiyu ...1975 年 77 巻 2 号 p. 383-390
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーAn immunoglobulin specific for RNase [EC 3.1.4.22] has been synthesized in a cell-free system containing either lymph node microsomes or polysomes or spleen poly-somes from rats previously immunized with RNase. The synthesis of anti-RNase immunoglobulin was demonstrated by affinity chromatography using an RNase-Sepharose column. Supporting evidence for the cell-free synthesis of immunoglobulin was obtained by separating the synthesized immunoglobulin from other proteins by DEAE-Sephadex A-25 column chromatography and by neutralization of RNase activity with the separated immunoglobulin. Lymph nodes and spleen had an almost equal capacity to synthesize the immunoglobulin to RNase. Under our experimental conditions, 5 to 15% of the total protein synthesis was directed toward immuno-globulin synthesis.抄録全体を表示PDF形式でダウンロード (583K) -
Katsutoshi ISHIKAWA, Koichi IWAI1975 年 77 巻 2 号 p. 391-398
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーAffinity chromatography based on the reaction between SH groups in protein and +HgC6H4CO groups in the p-mercuribenzoylaminoethyl derivative of Sepharose 4 B was examined with a crude preparation of calf thymus cysteine-containing histone. Adsorption of the histone onto the column by specific coupling was found to be optimal in 0.1M citrate buffer, pH 5.5, containing 5M urea to prevent any aggrega-tion of histones and their non-specific adsorption onto the column, and elution from the column was successfully performed by cleavage of the resulting S-Hg bond with urea-buffer solution containing 0.05M 2-mercaptoethanol. Under these conditions both the adsorption and elution were quantitative; no adsorption was observed when either SH-blocked histone or unsubstituted Sepharose was used. The cysteine-containing histone thus recovered, after further purification by Bio-Gel P-60 chromatography to remove some cysteine-containing nonhistone proteins contaminat-ing the starting material, showed a single band on polyacrylamide gel electrophoresis and an amino acid composition agreeing with the known sequence of this histone.抄録全体を表示PDF形式でダウンロード (1033K) -
Toshio KINOSHITA, Kiyoshi KANADA, Akio TSUJI1975 年 77 巻 2 号 p. 399-403
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーA simple chemical method for the determination of individual mucopolysaccharides in mixtures of dermatan sulfate and chondroitin sulfates by means of a single reagent was established, utilizing the difference in reaction rates of these polysac-charides with orcinol. To each 1ml of a sample mixture of standard dermatan sulfate and standard chondroitin sulfate (either 4- or 6-sulfate) was added 3ml of orcinol reagent and the resulting solution was heated in a boiling-water bath. After 20 and 60 min reaction, absorbances at 660nm were measured and the concentra- tions of individual mucopolysaccharides were calculated. High reproducibility was observed for the determination of dermatan sulfate in the presence of chondroitin sulfates. In addition, orcinol reaction for 90 min employing D-glucuronolactone as a standard appeared to be of practical value in the estimation of the uronic acid content of these mucopolysaccharides.抄録全体を表示PDF形式でダウンロード (311K) -
A New Flavin Enzyme Catalyzing the Reduction of Dihydrodipicolinate in Sporulating Bacillus subtilisI. Purification and PropertiesKinuko KIMURA1975 年 77 巻 2 号 p. 405-413
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーA dihydrodipicolinate reductase containing flavin was purified from sporulating Bacillus subtilis PCI 219. The purified enzyme appeared homogeneous by disc gel electrophoresis. Its molecular weight was estimated as 74, 000 by gel filtration on Sephadex G-200, and as 18, 500 by electrophoresis on sodium dodecylsulfate polyacryl-amid gel. These results suggest that the enzyme is composed of four subunits. The prosthetic group was identified as FMN, and one mole of the enzyme contained two moles of FMN. Both NADPH and NADH acted as coenzyme, though NADH was less effective. The enzyme also exhibited diaphorase activity. The pH optimum was 6.1. The enzyme was inhibited by dipicolinate but not by lysine or α, ε-diaminopimelate.抄録全体を表示PDF形式でダウンロード (623K) -
A New Flavin Enzyme Catalyzing the Reduction of Dihydrodipicolinate in Sporulating Bacillus subtilisII. Kinetics and Regulatory FunctionKinuko KIMURA, Tetsuhisa GOTO1975 年 77 巻 2 号 p. 415-420
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーDihydrodipicolinate reductase in Bacillus subtilis PCI 219 has FMN as a prosthetic group, and the hydrogen transfer pathway is considered to be NADPH→FMN→ dihydrodipicolinate. Lineweaver-Burk plots of the reciprocal of the activity against the reciprocal of the concentration of either of the two substrates, dihydrodipicolinate and NADPH, are consistent with a reaction mechanism involving interconversion of two free forms of the enzyme by the two substrates. The Km values obtained from the secondary plots are 0.77mM for dihydrodipicolinate and 72μM for NADPH. Inhibition by dipicolinate is competitive with NADPH and noncompetitive with dihydrodipicolinate, and shows positive cooperativity. The possible metabolic role of the reductase in sporulating Bacillus subtilis is discussed in connection with regulation of the biosyntheses of dipicolinate and diaminopimelate.抄録全体を表示PDF形式でダウンロード (385K) -
Noriko NISHIMURA, Masanobu JANADO1975 年 77 巻 2 号 p. 421-426
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーIt has been shown that sodium dodecyl sulfate (SDS) is capable of forming stable complexes with amylose and that fractionation of short-chain amyloses can be effected by SDS-gel electrophoresis. Using a well-defined amylose fraction (molecular weight 4, 000), the thermodynamic parameters pertaining to SDS-amylose interaction have been evaluated by means of frontal gel chromatography. The results are as follows: association constant (K)=5.0×103M-1 at 25° (pH 9.4); standard free energy change (ΔG°)=-5.1 kcal/mole; standard enthalpy change (ΔH°)=-5.8 kcal/mole; standard entropy change (ΔS°)=-2.3 (e.u.) and the maximum number of binding sites for SDS (n)=1. In the presence of 0.5-1% SDS, amylose migrates toward the anode upon gel electrophoresis, giving a compact band. High resolution of amylose fractions (released by treatment of amylopectin with debranching enzyme) has been attained using pore-size gradient gel electrophoresis.抄録全体を表示PDF形式でダウンロード (2185K) -
Crystallization, Properties, Carbohydrate Composition, and SubunitsMasaru HIMENO, Hideto OHHARA, Yasuaki ARAKAWA, Keitaro KATO1975 年 77 巻 2 号 p. 427-438
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーRat preputial gland β-glucuronidase [EC 3.2.1. 31] was purified by ammonium sulfate precipitation, ethanol fractionation, gel filtration on Sephadex G-200 and crystalliza-tion.
The purified enzyme appeared homogeneous on electrophoresis in polyacrylamide gel, and on analytical ultracentrifugation and had a molecular weight of approxi-mately 320, 000, and a sedimentation coefficient of 12S. SDS polyacrylamide gel electrophoresis indicated that the enzyme consisted of subunits with molecular weights of 79, 000, so the native enzyme appeared to be a tetramer. The Km with p-nitrophenyl β-D-glucosiduronic acid as substrate was about 0.53mM. The enzyme had a single pH optimum at 4.5.
The enzyme had a very low content of sulphur-containing amino acid and con-tained 5.7% carbohydrate, consisting of mannose, glucose, fucose, galactose, and glucosamine in a ratio of 44; 9; 6; 2; 41. Sialic acid was not detected in the crystallized enzyme.抄録全体を表示PDF形式でダウンロード (3067K) -
Requirement for Ribosomal Subunits and the Effect of NH4+ IonsNaoko ARAI, Yoshito KAZIRO1975 年 77 巻 2 号 p. 439-447
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーAt low NH4+ concentrations, 50S ribosomal subunits from E. coli were fully active in the absence of 30S ribosomal subunits, in forming a complex with the polypeptide chain elongation factor G (EF-G) and guanine nucleotide (ternary complex forma-tion), and also in supporting EF-G dependent hydrolysis of GTP (uncoupled GTPase reaction). However, both activities were markedly inhibited on increasing the con-centration of the monovalent cation, and at 160mM NH4+, the optimal concentration for polypeptide synthesis in a cell-free system, almost no activity was observed with 50S ribosomes alone. It was found that the inhibitory effect of NH4+ was reversed by addition of 30S subunits. Thus, at 160mM NH4+, only 70S ribosomes were active in supporting the above two EF-G dependent reactions, whereas at 20mM NH4+ 50S ribosomes were almost as active as 70S ribosomes. Kinetic studies on inhibition by NH4+ of the formation of 50S ribosome•EF-G•guanine nucleotide complex, indicated that the inhibition was due to reduction in the number of active 50S ribosomes which were capable of interacting with EF-G and GTP at higher concen-trations of NH4+. The inhibitory effects of NH4+ on ternary complex formation and the uncoupled GTPase reaction were markedly influenced by temperature, and were much greater at 0° than at 30°. A conformational change of 50S subunits through association with 30S subunits is suggested.抄録全体を表示PDF形式でダウンロード (685K) -
Susumu KURIOKA, Fumihide INOUE1975 年 77 巻 2 号 p. 449-455
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーBoth cationic and anionic detergents were found to precipitate fibrinogen by forming fibrinogen-detergent complexes. These complexes were soluble in distilled water, but the aqueous solutions were very unstable and the complexes precipitated in the presence of salt.
In the interaction of fibrinogen with the cationic detergent, stearyltrimethyl-ammonium chloride, approximately 160 molecules of detergent were found to bind to one molecule of fibrinogen. In distilled water, the fibrinogen-stearyltrimethylammo-nium complex (FG-STA(Cl)) remained soluble in the presence of thrombin [EC 3.4.21.5], although the same peptides were released as those released from fibrino-gen. Precipitation of FG-STA(Cl) by salt was found to be closely related to adsorption of the anion of the salt by the complex. Further addition of salt resulted in solubilization of the precipitate, and the solubilization was also due to further adsorption of the anion onto the precipitate.抄録全体を表示PDF形式でダウンロード (1331K) -
Susumu KURIOKA, Fumihide INOUE, Fukuichi NAKADA1975 年 77 巻 2 号 p. 457-461
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーStearyltrimethylammonium chloride was used to isolate human fibrinogen, and purified protein was obtained by removing the detergent bound to it. Medium consisting of 0.015-0.03mM fibrinogen-detergent complex, 0.85M NaCl, 0.03M sodium caprylate, and 30% ethanol was found to be effective for renaturation of fibrinogen from the complex. The purified fibrinogen did not form any fibrils on incubation for 15 days with Ca+2 at pH 7.2, and 37° The clottability of the purified fibrinogen was over 99%. Immunochemical studies showed that the purified fibrinogen produced one precipitation line with a mixture of anti-human fibrinogen and anti-human serum. Although highly purified, the fibrinogen preparation still contained a trace of plasminogen.抄録全体を表示PDF形式でダウンロード (1927K) -
IX. Changes in the Fluorescence Polarization of FAD upon Complex FormationKunio YAGI, Fumio TANAKA, Nobuko OHISHI1975 年 77 巻 2 号 p. 463-468
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリー1. The fluorescence polarization, P, of FAD increased on complex formation with the apoenzyme of D-amino acid oxidase [D-amino acid: O2 oxidoreductase (deaminat-ing), EC 1.4.3.3]. The time course of the increase was monophasic. The values of P were estimated to be 0.04, 0.4, and 0.4 for FAD, the enzyme and the enzyme-benzoate complex, respectively.
2. The value of P of the enzyme is dependent on its concentration, indicating that the degrees of dissociation of FAD in the monomer and dimer are different. The dissociation constant was calculated to be 7×10-7M for the monomeric form of the enzyme. This value is far larger than the value for the dimeric form of the enzyme, 1×10-8M, calculated from equilibrium dialysis data.
3. Changes in the fluorescence polarization of the enzyme due to changes in solution pH or temperature can be explained in terms of the monomer-dimer equilibrium.抄録全体を表示PDF形式でダウンロード (409K) -
The “Single-Addition” of 2'(3')-O-Dihydrocinnamoyl-nucleoside 5'-Diphosphate to a Primer OligonucleotideYo KIKUCHI, Keiko HIRAI, Kenji SAKAGUCHI1975 年 77 巻 2 号 p. 469-472
発行日: 1975/02/25
公開日: 2008/11/18
ジャーナル フリーA method was developed for stepwise synthesis of oligonucleotides of defined sequence using 2'(3')-O-dihydrocinnamoyl-nucleoside 5'-diphosphates as substrates for polynucleotide phosphorylase [EC 2.7.7.8]. Polynucleotide phosphorylase from Thermus thermophilus catalyzed the transfer of one 2'(3')-O-dihydrocinnamoyl-adenylate residue from 2'(3')-blocked ADP to the 3'-terminus of the primer trinucleo-side diphosphate, ApApA. The product was 2'(3')-substituted triadenylyladenosine. The blocking group, dihydrocinnamoyl, could be removed completely from the product without destruction of the phosphodiester bond using α-chymotrypsin [EC 3.4.21. 1] at neutral pH.抄録全体を表示PDF形式でダウンロード (253K)
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