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Volume 78, Issue 1
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Kaoru SEGAWA, Kenji IKEHARA, Yoshimi OKADA1975 Volume 78 Issue 1 Pages 1-7
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA-Protein was isolated from a purified male-specific filamentous phage fd particle. A-Protein has a molecular weight of approximately 60, 000 daltons, as estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The amino-terminal residue was glycine as determined by the dansylation technique. Amino acid analysis showed that histidine, arginine, and cysteine, which are not contained in B-protein, are present in A-protein.View full abstractDownload PDF (969K) -
I. Purification and Some PropertiesTaro OGISO, Takao NODA, Yuko SAKO, Yoshio KATO, Masahide AOYAMA1975 Volume 78 Issue 1 Pages 9-17
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSTo clarify the properties and functions of a trypsin inhibitor from Japanese barley in comparison with the inhibitor from Pirkka barley, an inhibitor was isolated from the barley Hordeum distichum L var. emend Lamark by extraction with 1% NaCl, ammonium sulfate fractionation and repeated chromatography on DEAE-cellulose and CM-cellulose. The final purified preparation of the inhibitor was found to be homogeneous by both chromatographic and electrophoretic analysis. The inhibitor was thermostable and was stable over the broad pH range from 2 to 11. No inhibition was observed by heavy metal ions and many reagents at 10-2M, except that p-chloromercuribenzoate caused a 69% loss of activity. The inhibitor was subjected to isoelectric focusing at pH 7.51 and its molecular weight was calculated to be 14, 200±900 by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The apparent dissociation constant for the complex between the inhibitor and trypsin[EC 3. 4. 21. 4] was 1.64×10-7M with casein as a substrate. One microgram of purified inhibitor inhibited 1.5μg of pure trypsin in the hydrolysis of α-Nbenzoyl-DL-arginine-p-nitroanilide. By chemical modification of arginyl residues in the inhibitor with 1, 2-cyclohexanedione, the inhibitor was shown to be an arginine inhibitor. The inhibitor contained relatively many basic amino acids and few halfcystines as compared with Pirkka barley trypsin inhibitor.View full abstractDownload PDF (1382K) -
Chen-Sheng LIU1975 Volume 78 Issue 1 Pages 19-29
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSOne of the 2 main hemoglobins of the sea snake Pelamis platurus, (the Yellow-bellied sea snake) comprising about 70% of the total hemoglobin, was separated by DEAE-Sephadex column chromatography. From results of gel filtration and iron content determination, both intact sea snake hemoglobin, and the isolated major hemoglobin, were concluded to be composed of 4 subunits with a molecular weight of 66, 000-67, 000 daltons. Separation of the chains of globin of the major hemoglobin by CM 52 column chromatography gave 3 peaks, named, chains a, b, and c. The approximate molecular weights of chains a, b, and c were deduced by SDS gel electrophoresis to be 14, 000, 16, 000, and 20, 000 daltons, respectively. The peptide maps and amino acid compositions of the three chains were distinctly different. N-Terminal and C-terminal amino acid sequence studies real that chains a, b, and c represented the α-chain, β-chain, and β'-chain, the β'-chain differing from the normal β-chain in having a C-terminal sequence of -Arg-Leu-His-Tyr. From the peak areas of the 3 chains obtained by CM 52 column chromatography, and the peak sizes of the 3 bands separated by SDS gel electrophoresis, it was concluded that the sea snake hemoglobin is composed of a hybrid tetramer, α2ββ'.View full abstractDownload PDF (4779K) -
II. Comparative Studies on Multiple Forms of Cathepsin AKeiichi MATSUDA, Eiichi MISAKA1975 Volume 78 Issue 1 Pages 31-39
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe multiple forms of cathepsin A (AI, AII, and AIII) purified from the lysosome fraction of rat liver by Sephadex G-200 and DEAE-Sephadex chromatographies were studied comparatively.
Forms AI, AII, and AIII were stable between pH 3.0 and 5.5, and had pH optima for CBZ-Glu-Phe at 5.6, 5.8, and 5.9, respectively. These activities were rapidly lost on heating above 60°. Their isoelectric points were at 4.7, 4.8, and 4.9, and the Michaelis constants for CBZ-Glu-Phe were calculated as 10, 6.6, and 4.2×10-4M, respectively.
Activity was inhibited by Ag+, Au3+, Hg2+, iodine, and p-chloromercuribenzoate (PCMB). Diisopropyl fluorophosphate (DFP), phenylmethanesulfonyl fluoride (PMSF), toluenesuffonyl fluoride (TSF), and sodium dodecyl sulfate (SDS) were inhibitory at a concentration of 10-3M. Soybean trypsin inhibitor, pepstatin, leupeptins, and antipain were not inhibitory, while chymostatin caused slight inhibition. No distinct difference was observed in the effects of these compounds on the multiple forms of cathepsin A despite differerences in the molecular weights of these forms (100, 000, 200, 000, and 420, 000, respectively).
In immuno-diffusion analysis, cathepsin AI, AII, and AIII which had been treated with EDTA, dithiothreitol, PCMB, and a high concentration of NaCl, gave the same precipitin patterns as the untreated enzymes, but treatment with 6M urea caused a slight alteration of the pattern. After SDS-treatment (50mM or more), the precipitin lines of these multiple forms fused and gave a single, identical line. This suggests that the different forms of the cathepsin A are all composed of subunits which are immunologically identical or closely related, and that the subunits are mainly bound by hydrophobic forces. This conclusion is supported by results obtained by poliacrylamide gel electrophoresis in the presence of SDS.View full abstractDownload PDF (2400K) -
Takashi SHIMIZU1975 Volume 78 Issue 1 Pages 41-49
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSRecombination of ciliary dyneins of Tetrahymena pyriformis with the outer fibers was investigated using turbidimetry, co-sedimentation analysis and electron microscopy. As reported by Gibbons, 30S dynein could recombine with the outer fibers, while 14S dynein did to so a lesser extent. At acidic pH, however, most of the 14S dynein was also rebound to the outer fibers. When an excess of crude dynein fraction was added to the outer fiber fraction at pH 8.2, electron microscopic observations showed that the outer doublet microtubules were decorated not only with arms but also with other electron-dense materials. On the other hand, when crude dynein fraction was mixed with the outer fibers in an appropriate quantity, only arms were reconstituted at the regular positions of A-subfibers. ATP had an inhibitory effect on the recombination of dynein with the outer fibers.View full abstractDownload PDF (2283K) -
Chromatophores from Rhodospirillum rubrumTomihiko HIGUTI, Tatsuo ERABI, Tomisaburo KAKUNO, Takekazu HORIO1975 Volume 78 Issue 1 Pages 51-56
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe role of ubiquinone-10 in the activities for the reduction of free cytochrome c2 and bound cytochrome cc' by succinate was studied with chromatophores from a blue-green mutant (G-9) of Rhodospirillum rubrum.
1. By a single extraction with isooctane, approximately 90% of ubiquinone-10 was easily removed from the chromatophores. In the extracted chromatophores, the activity for succinate-cytochrome c2 reduction decreased to 5-10% of the original activity. This depressed activity was mostly restored by adding ubiquinone-10.
The remaining quinone was hardly extractable, even by repeated extractions. With repeatedly extracted chromatophores, the activity for succinate-cytochrome c2 reduction was mostly restored to the same extent as with once-extracted chromatophores, whereas the extent of inhibition of the activity by antimycin A gradually fell.
2. In isooctane-extracted chromatophores, the activity for the reduction of bound cytochrome cc' by succinate under anaerobic conditions decreased to 35 to 95% of the original level. With chromatophores in which the remaining activity was as low as 40% of the original level, the activity was partially restored by adding ubiquinone-10, but this was not the case with chromatophores in which the remaining activity was higher than approximately 50% of the original level.View full abstractDownload PDF (446K) -
Kihachiro HORIIKE, Yasuzo NISHINA, Yoshihiro MIYAKE, Toshio YAMANO1975 Volume 78 Issue 1 Pages 57-63
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe acetylenic substrate, D-2-amino-4-pentynoic acid (D-propargylglycine), was oxidatively deaminated by hog kidney D-amino acid oxidase [EC 1. 4. 3. 3], with accompanying inactivation of the enzyme. The flavin which was extracted by hot methanol from the inactivated enzyme was identical with authentic FAD by thinlayer chromatography and circular dichroism. The excitation spectrum of emission at 520nm of the released flavin was very similar to the absorption spectrum of oxidized FAD. The released flavin was reduced by potassium borohydride. The apoenzyme prepared after propargylglycine treatment did not show restored D-amino acid oxidase activity on adding exogenous FAD. The absorption spectrum of this inactivated apoenzyme showed absorption peaks at 279 and 317nm, and a shoulder at about 290nm. These results strongly indicate that the inactivation reaction is a dynamic affinity labeling with D-propargylglycine which produces irreversible inactivation of the enzyme by a covalent modification of an amino acid residue at the active site.View full abstractDownload PDF (581K) -
Superprecipitation of ActomyosinYuriko TAWADA, Hiroyuki OHARA, Tatsuo OOI, Katsuhisa TAWADA1975 Volume 78 Issue 1 Pages 65-72
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSNon-polymerizable tropomyosin was prepared by the digestion of several C-terminal residues of tropomyosin with carboxypeptidase A [EC 3. 4. 12. 2]. The intrinsic viscosity and molecular weight of the non-polymerizable tropomyosin were almost the same as those of untreated tropomyosin. Like untreated tropomyosin, the non-polymerizable tropomyosin in combination with troponin repressed the superprecipitation of actomyosin in the absence of calcium, while this repression was released by addition of calcium. However, the curve representing the superprecipitation rate as a function of pCa was less steep than that found with actomyosin containing untreated tropomyosin: in the former case, the rate increased to a plateau over about 2 pCa units, while in the latter case, it did so over about 1 pCa unit. These experimental results provide evidence that the “co-operation” in the regulation mechanism of skeletal muscle contraction, which is indicated by the steep curve of the contraction versus pCa relation, is mediated by tropomyosin-tropomyosin interaction along the thin filament.View full abstractDownload PDF (1397K) -
Shun-ichi OHNISHI, Koscak MARUYAMA, Setsuro EBASHI1975 Volume 78 Issue 1 Pages 73-81
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe three troponin components, TN-C, TN-I, and TN-T, were spin-labeled with two different derivatives of the nitroxide radical, a maleimide and an imidazole reagent. The ESR spectra of various combinations of labeled and unlabeled components were measured both in the presence and absence of calcium. Conformational changes due to the binding of the components and also due to the binding of calcium were sensitively detected in many combinations as large changes in the spectrum. The conformation of TN-C was modified by both TN-T and TN-I. The effects were larger in the presence of calcium than in its absence. In the presence of calcium, TN-T. and TN-I both showed large effects with the maleimide label, while TN-I showed a larger effect than TN-T with the imidazole label. In the absence of calcium, the effect of TN-I was larger than that of TN-T. The sensitivity of TN-C to calcium was magnified by component binding, since the conformation of TN-C itself was not greatly affected by calcium. The conformation of TN-I was greatly altered only in the presence of both TN-C and calcium. This indicates that the calcium-induced conformational change in TN-C is transmitted to the adjacent TN-I. In reconstituted troponin, the conformation of TN-C was more influenced by TN-I in the presence of calcium and by TN-T in its absence as indicated by the imidazole label. With the maleimide label, TN-I was more influential in the absence of calcium. The effect of calcium on the troponin complex was to make the local environment of the label more rigid. The half-maximal effect was observed at 2×10-6M calcium with TN-I in various complexes, while it was 10-5M with TN-C in the complexes. In any case the calcium effects became discernible at 10-6M and saturated at 10-4M.View full abstractDownload PDF (663K) -
The Physiological Functions of the Two Routes of Myosin Adenosinetriphosphatase in Muscle ContractionAkio INOUE, Yuji TONOMURA1975 Volume 78 Issue 1 Pages 83-92
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe rates of the ATPase [EC 3. 6. 1. 3] reaction of the H-meromyosin-F-actin-relaxing protein system were measured in 2mM MgCl2, 50mM KCl, and 10mM Tris-HCl at pH 7.8 and 20° in the presence and absence of 0.05-0.1mM Ca2+ ions. The concentrations of H-meromyosin (HMM) and the F-actin-relaxing protein (F-A-PR) complex were 3.4 and 3mg/ml, respectively, and the ATPase reaction was coupled with 4mg/ml of pyruvate kinase [EC 2. 7. 1. 40] and 1 or 20mM phosphoenolpyruvate to regenerate ATP. The amount of ADP bound to HMM during the ATPase reaction was determined by measuring the amount of ADP remaining in the reaction mixture. The amount of ATP bound to HMM was determined by subtracting the amount of bound ADP from the total amount of nucleotides bound to HMM, which was measured by a rapid flow-dialysis method. The following results were obtained.
1. The ATPase activity of the HMM-F-A-RP system increased linearly with increase in the amount of ATP added, and was independent of the presence of 0.05mM Ca2+, when the amount of ATP added was less than 1mole/mole of HMM. In the presence of 0.05mM Ca2+, the ATPase activity reached a maximal level when 1.2-1.5mole of ATP was added per mole of HMM, and maintained this level even at 3moles of added ATP/mole of HMM. In the presence of 3mM EGTA, the ATPase activity decreased with increase in the amount of ATP added, from 1.5 to 3moles of ATP/mole of HMM, and reached the level of the HMM ATPase reaction at 3moles of added ATP/mole of HMM. Similar results were observed when the concentration of HMM was maintained at 3.4mg/ml and the concentration of the F-A-RP complex was decreased from 3 to 1 or 0.5mg/ml.
2. When the amount of ATP added was less than 1.2mole/mole of HMM, almost all the added nucleotide was bound to HMM as ADP. In the presence of 0.1mM Ca2+, the amount of ADP bound to HMM remained constant in the ATP concentration range of 1.5 to 3moles/mole of HMM, while in the presence of 3mM EGTA the amount of ADP bound to HMM decreased with increase in the ATP concentration above 1.5mole/mole of HMM. At 3moles of added ATP/mole of HMM, 0.5mole of ADP was bound per mole of HMM, this being equal to that observed with the HMM-ATP system.
3. The binding of ATP to HMM was only observed when the amount of ATP added was more than 1mole/mole of HMM. In the presence of EGTA, the amount of bound ATP increased with increase in the amount of ATP added, and was about 1.2mole/mole of HMM at 3moles of added ATP/mole of HMM. This value was equal to that observed with the HMM-ATP system. The amount of bound ATP was proportional to the extent of inhibition of acto-HMM ATPase caused by removal of Ca2+ ions. The binding of ATP to HMM was markedly inhibited by the addition of 0.1mM CaCl2.
It is concluded from these results that the reactive myosin-phosphate-ADP complex, MADPP, is the reaction intermediate of actomyosin ATPase, that the ATPase does not require binding of ATP to the complex, and that formation of the myosin-ATP complex, MATP, is required for regulation of actomyosin ATPase in the presence of RP by trace amounts of Ca2+ ions.View full abstractDownload PDF (701K) -
Kikuko TAKEUCHI, Nobuhiko SHIBATA, Nobuyuki SENDA1975 Volume 78 Issue 1 Pages 93-103
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSMyosin was isolated from leucocytes in horse arterial blood by the same procedures used for the isolation of myosin from skeletal muscle. The Ca2+-, EDTA-, and Mg2+-ATPase [EC 3. 6. 1. 3] activities of the protein were 0.148, 0.147, and 0, 001μamoles/min/mg, respectively, in 0.5M KCl at pH 7.0 and 25°. The Ca2+-ATPase activity decreased with decrease in the ionic strength. No difference was found between leucocyte myosin and skeletal myosin in the pH profiles of Ca2+- and EDTA-ATPases. The rate and amount of the initial burst of Pi liberation of leucocyte myosin were 0.002μmoles/min/mg and 0.83moles/4.8×105g, respectively. Leucocyte myosin aggregated into filaments of 0.3μm length and 150A diameter, which had a bare shaft and irregular projections. At high ionic strength, the protein bound to skeletal muscle F-actin to form a complex with the characteristic arrowhead structure.View full abstractDownload PDF (5500K) -
Purification and Characterization of the EnzymeMotoaki ANAI, Toshihiko MIHARA, Masayoshi YAMANAKA, Tateki SHIBATA, Ya ...1975 Volume 78 Issue 1 Pages 105-114
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA deoxyribonuclease, which requires nucleoside triphosphate for reaction, has been purified about 150-fold from extracts of Bacillus laterosporus. Potassium phosphate and ethylene glycol stabilize the purified enzyme. The enzyme degrades doublestranded DNA about 100 times faster than heat-denatured DNA in the presence of nucleoside triphosphate. Double-stranded DNA is not degraded to any measurable extent in the absence of ATP, but the enzyme exhibits activity toward denatured DNA in the absence of nucleoside triphosphate, and this activity seems to be an intrinsic property of this enzyme protein. The optimum pH is 8.5 and the maximum activity is obtained in the copresence of Mg2+ (8.0×10-3M) and Mn2+ (7.0×10-5M). ATP and dATP are most effective and nucleoside di- or monophosphates are ineffective. ATP is converted to ADP and inorganic phosphate during the reaction and the ratio of the amount of ATP cleaved to that of hydrolyzed phosphodiester bonds of DNA is about 3:1. An inhibitor of the enzyme was observed in bacterial extracts prepared by sonic disruption; the inhibitory substance is produced in the bacteria in the later stages of cell growth. Preliminary results show that the inhibitor emerged near the void volume of a Sephadex G-200 column, and was relatively heat-stable, RNase-resistant, and DNase-sensitive.View full abstractDownload PDF (692K) -
The Mode of Action of the EnzymeMotoaki ANAI, Masayoshi YAMANAKA, Tateki SHIBATA, Toshihiko MIHARA, Ta ...1975 Volume 78 Issue 1 Pages 115-121
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe acid-soluble products of exhaustive digestion of native DNA with Bacillus laterosporus DNase consist of 6.5% of mononucleotides and 93.5% of oligonucleotides with an average chain length of 3.2. The results of viscometric studies and inactivation of transforming DNA indicate the existence of acid-insoluble intermediates and the selective degradation of the population of substrate molecules rather than a random nucleolytic action. Furthermore, sucrose density gradient analysis of partially digested DNA showed that the initial DNA added as a substrate disappeared progressively during the reaction, being replaced by much more slowly sedimenting acid-insoluble materials, which were eventually degraded into acid-soluble end products during the reaction; products intermediate in size between these two components were not detectable. Studies with DNA labeled at the 3'-terminus indicate that Bacillus laterosporus DNase does not attack DNA from 3'-hydroxyl ends to yield acid-soluble or acid-insoluble materials in a random manner. The results presented in this paper indicate that the nature of the attack of B. laterosporus nuclease is similar to that previously proposed for Micrococcus luteus DNase. The possibility of the sequential release of acid-insoluble intermediate fragments as well as acid-soluble products from the terminal portion of DNA by the enzyme is discussed.View full abstractDownload PDF (487K) -
Ryuji HOSONO, Hisako HOSONO, Sigeru KUNO1975 Volume 78 Issue 1 Pages 123-129
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe cellular levels of thymidine nucleotide derived from [3H] thymine or [3H] thymidine were followed under various enviromental conditions with a thymine-requiring mutant of Escherichia coli. It was shown that the pool sizes varied greatly with the growth conditions; that is, with growth temperature, inhibition of DNA synthesis or replacement of thymine with thymidine.
In the strain used here, the level of compound X, presumably dTDP-sugar, was very much higher than those of other thymidine nucleotides. It is suggested that the conversion of thymine to thymidine is rate-limiting, while the conversions of thymidine to dTMP, and of dTMP to dTDP are more rapid than other steps in the salvage pathway of thymidine nucleotide.View full abstractDownload PDF (519K) -
Masafumi FUJIMOTO, Shinichi MIHARA, Tadashi OKABAYASHI, Tooru SUGASE, ...1975 Volume 78 Issue 1 Pages 131-137
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA radioimmunoassay procedure for guanosine 3', 5'-cyclic monophosphate (CGMP) is described. The procedure is based on competitive binding between [3H] CGMP and non-radioactive CGMP, with separation of bound and unbound CGMP by Millipore filtration. The binding reaction showed very high specificity to CGMP, had a broad pH optimum, and reached equilibrium within a short time. A simple procedure for the purification of assay samples using Dowex AG 50W-X2 resin is also described.
CGMP contents in urine samples were assayed without purification. Injection of glucagon into healthy human volunteers resulted in a small but significant reduction in urinary CGMP level, whereas CAMP excretion increased dramatically.View full abstractDownload PDF (493K) -
Shoko MIYAZAWA, Takehiko SAKURAI, Yasuko SHINDO, Mitsuo IMURA, Takashi ...1975 Volume 78 Issue 1 Pages 139-147
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. Tryptophan was administered to rats under various nutritional conditions: fasted for 24hr, fasted and refed with glucose or corn-oil, fasted and administered glycerol intramuscularly, and nonfasted.
2. The changes in the contents of glycolytic intermediates in the livers indicated that the phosphoenolpyruvate carboxykinase [EC 4. 1. 1. 32] reaction is inhibited by tryptophan administration in all groups of rats. The inversely related changes in the contents of malate and phosphoenolpyruvate were associated with the accumulation of quinolinate in the livers. The content of quinolinate which exhibited the half-maximal effect on the contents of both metabolites was 0.1-0.2μmole per g liver.
3. The rate of incorporation of 3H from 3H2O into the total hepatic fatty acids was increased about 2-fold by the administration of this amino acid to the fasted rats. The enhancement of the rate was closely related to the increase in the citrate content. The hyperlipogenesis was also related to the decrease of acetyl-CoA and the increase of malonyl-CoA. The content of long-chain acyl-CoA was not affected. These effects of tryptophan administration on the hepatic fatty acid metabolism were found in all groups of rats. The liver content of glycerol 3-phosphate was decreased by tryptophan administration and was markedly increased by glycerol injection. The injection of glycerol into the control and the tryptophan-treated rats produced a marked increase of glycerol 3-phosphate but did not affect the rate of fatty acid synthesis in the livers of either group.
4. It may be concluded that, in the livers of rats under various nutritional conditions, the short-term control of fatty acid synthesis by tryptophan administration is most likely due to the activation of acetyl-coenzyme A carboxylase [EC 6. 4. 1. 2] by citrate.View full abstractDownload PDF (723K) -
XIII. Mechanism of Selective Inhibition of the Active Transport Reactions for Proline, Leucine, and Succinate by Zinc IonsYasuhiro ANRAKU, Fumiko GOTO, Emi KIN1975 Volume 78 Issue 1 Pages 149-157
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA mutant (S-1) of Escherichia coli which lacks succinate dehydrogenase [EC 1. 3. 99. 1] but has normally succinate transport system, and various oxidase activities other than succinate, was isolated from the strain U24. Using these strains studies were made on the effects of zinc ions on the active transport reactions for succinate, proline, and leucine. Zinc ions inhibited succinate transport reaction and succinate oxidation by intact cells.
The active transport reaction for proline, which was supported by endogenous energy source in intact cells, was slightly inhibited by zinc ions. This inhibition was not reversed by large excess of magnesium ions. The initial rates of active uptakes of proline were increased by exogenous energy sources such as succinate and glycerol and zinc ions greatly inhibited these. However, D-lactate dependent proline uptake was enhanced slightly by the presence of zinc ions.
It was found that zinc ions at a high concentration enhanced the steady level of proline accumulation in cells. This mechanism was studied in detail and we concluded that zinc ions inhibited completely the exchange-exit reaction for proline.
Effects of zinc ions on the active transport reaction for leucine were rather simple when compared with these for proline. Zinc ions inhibited strongly the initial rates of leucine uptakes which were driven by endogenous and exogenous energy sources. The ions also inhibited the exchange-exit reaction.View full abstractDownload PDF (683K) -
XIV. Preferential Inhibition of Oxidase Activites and Active Transport Reactions for Amino Acids by AzidebenzenesEmi KIN, Yasuhiro ANRAKU1975 Volume 78 Issue 1 Pages 159-163
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS4-Methylazidebenzene and various azidebenzene derivatives were prepared, and the effects of these compounds on oxidase activities and active transport reactions for amino acids in Escherichia coli cells were studied.
Azidebenzenes inhibited succinate oxidation by intact cells preferentially to glycerol oxidation. However, the azidebenzenes could not inhibit succinate oxidation which was not coupled to phosphorylation. The compounds inhibited succinatedriven proline uptake much more strongly than isoleucine uptake.
Unlike sodium azide and diphenyl phosphorazidate, azidebenzenes did not inhibit membrane-bound, Mg2+-requiring ATPase [EC 3. 6. 1. 3] of E. coli. Reactivities of various azide compounds in the mechanism of inhibition for energy transducing and energy transforming reactions were discussed briefly.View full abstractDownload PDF (331K) -
XV. Comparative Studies on the Effects of Various Energy Poisons on the Oxidative and Phosphorylating Activities, and Energy Coupling Reactions for the Active Transport Systems for Amino AcidsYasuhiro ANRAKU, Emi KIN, Yasuhito TANAKA1975 Volume 78 Issue 1 Pages 165-179
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe effects of various energy poisons on oxidation of respiratory substrate, synthesis of cellular ATP, and energy transformation reaction in intact Escherichia coli cells were studied systematically. Various mutants were, therefore, used in which specific functions in the energy-transducing reactions are defective or altered. The energy poisons examined were: sodium azide, DPPA and azidebenzenes which are inhibitors of respiratory-chain phosphorylation, SF6847, and CCCP which are known to be uncouplers, zinc sulfate which is an inhibitor for certain dehydrogenases, and sodium arsenate and sodium fluoride which are inhibitors of glycolytic synthesis of ATP.
The preferential inhibitions occurred in the oxidation reactions with certain respiratory substrates by energy poisons used. DPPA inhibited glycerol oxidation much more strongly than succinate oxidation. However, DPPA could inhibit the oxidation of both glycerol 3-phosphate and succinate by membrane fraction strongly while the oxidation of NADH and D-lactate slightly. It inhibited glycerol 3-phosphate dehydrogenase [EC 1. 1. 2. 1] strongly as well as succinate dehydrogenase [EC 1. 3. 3. 99. 1]but not D-lactate dehydrogenase of membrane fraction. MAB and other azidebenzene derivatives inhibited succinate oxidation preferentially. SF6847 and CCCP inhibited succinate oxidation strongly, while sodium azide inhibited it weakly and these three poisons were less inhibitory for glycerol oxidation.
DPPA, sodium azide, SF6847, and CCCP inhibited the synthesis of ATP coupled with respiration but not with glycolysis. Zinc sulfate inhibited the cellular ATP synthesis coupled with either respiration or glycolysis.View full abstractDownload PDF (1176K) -
Susumu TAKAKUWA1975 Volume 78 Issue 1 Pages 181-185
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA soluble cytochrome c-552 from Thiobacillus thiooxidans was highly purified and its physico-chemical properties were studied. The absorption maxima were at 552, 523, 418nm in the reduced from and at 412nm in the oxidized form. The pyridine hemochrome spectrum was the same as that of other cytochromes c. The molecular weight, estimated by the gel filtration method, was found to be 12, 600. The isoelectric point was determined to be 9.2-9.3 by the electrofocusing technique. The standard oxidation-reduction potential of this cytochrome was +0.247 V.View full abstractDownload PDF (964K) -
Minoru HAMADA, Kin-Ichi OTSUKA, Nobuyuki TANAKA, Kyoko OGASAHARA, Kich ...1975 Volume 78 Issue 1 Pages 187-197
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSLipoate acetyltransferase [acetyl-CoA: dihydrolipoate S-acetyl-transferase, EC 2. 3. 1. 12], the core enzyme of the pyruvate dehydrogenase complex, has been highly purified by gel chromatography on Sepharose 6B and sucrose density gradient centrifugation in the presence of potassium iodide. The native enzyme has a sedimentation coefficient (S020, W) of 26.7S and a diffusion coefficient (D020, W) of 1.25×10-7cm2sec-1. The weight-average molecular weight was estimated to be 1.8 million from the sedimentation equilibrium data. The content of right-handed α helix in the enzyme molecule was estimated to be about 25% by optical rotatory dispersion and about 22% from the circular dichroism spectra. The enzyme was found to contain about 23 moles of protein-bound lipoic acid per mole of enzyme; some other properties are also reported.
Lipoate acetyltransferase dissociated to yield a single subunit with a molecular weight of 74, 000 as estimated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate and by gel filtration on Bio-Gel in 6M guanidine-HCl. The molecular weight was also estimated to be 74, 000 from sedimentation equilibrium data in 6M guanidine-HCl containing 0.1M 2-mercaptoethanol. Evidence is presented that 1 molecule of lipoate acetyltransferase apparently consists of 24 very similar subunits, each of which contains NH2-terminal alanine. Each subunit contains 1 molecule of covalently bound lipoic acid.View full abstractDownload PDF (1624K) -
Masanobu JANADO1975 Volume 78 Issue 1 Pages 199-203
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (266K) -
Kunihiro KUWAJIMA, Katsutoshi NITTA, Shintaro SUGAI1975 Volume 78 Issue 1 Pages 205-211
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSIn order to clarify how the electrophoretic behavior reflects the conformational transition of globular proteins, moving boundary electrophoresis was applied to analysis of the acid conformational change of α-lactalbumin. The appearance of only a single electrophoretic boundary in the transition region of the protein suggests a very rapid transition with a half-time estimated to be smaller than 7 min on the basis of the theory of isomerizing systems in electrophoresis. The transition is clearly reflected in the dependence of the mobility on the protein net charge, which shows a sigmoidal curve closely similar to that obtained by a Linderstr∅m-Lang pH-titration plot for the carboxyl groups of α-lactalbumin. It was also concluded from the transition curves that the acidfication does not result in complete unfolding, but that a compact structure is maintained in the acidic region with an apparently expanded form as compared to the native state of the protein. All results obtained by electrophoresis were also supported by the results of pH-jump studies, analytical gel chromatography, and CD measurements.View full abstractDownload PDF (1445K) -
Izumi OHKAWA, Bunji MARUO, Makoto KAGEYAMA1975 Volume 78 Issue 1 Pages 213-223
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe effects of pyocin S2, a bacteriocin produced by Pseudomonas aeruginosa strain M47, on several processes in susceptible bacterium have been examined. Lipid synthesis, measured in terms of [32P] phosphate, [14C]acetate or [2-3H]glycerol incor-poration into lipid fractions, was halted almost completely soon after pyocin S2 addition. When cell suspensions were treated with various amounts of pyocin S2, the extent of inhibition of lipid synthesis was proportional to the ratio of killed bacteria. Protein synthesis was not essential for the inhibition. Degradation of lipid due to pyocin S2 was not detected. Pyocin S2 also affected protein and nucleic acid syntheses, but these inhibitions appeared with a delay of about 10 min after the cessation of lipid synthesis.
The effect of trypsin [EC 3. 4. 21. 4] on the viability of cells which had adsorbed pyocin S2 was also investigated: the cells went through a period when the destruction of pyocin S2 by trypsin restored the colony-forming ability of the cells (stage I). Then transition to a second state in which the cells lost viability irrespective of trypsin treatment (stage II) took place. The transition from stage I to stage II depended on the energy metabolism of the cells and followed first-order kinetics with a rate proportional to the number of killing units of adsorbed pyocin S2.
The residual capacity for lipid synthesis in cells which had adsorbed pyocin S2 after trypsin treatment at various times indicated that lipid synthesis was inhibited only in the cells at stage II of pyocin S2 action.View full abstractDownload PDF (854K) -
Taichi USUI, Hiroshi SUGIYAMA, Shuichi SETO, Shimpei ARAYA, Tosiki NIS ...1975 Volume 78 Issue 1 Pages 225-227
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe 13C NMR spectra of glucans from Streptococcus mutans JC-2 show that those glucnas have α-(1, 3) and α-(1, 6) linkages.View full abstractDownload PDF (1035K) -
Nobuo UEMITSU, Haruoka OHASHI, Hiroyuki MATSUMIYA1975 Volume 78 Issue 1 Pages 229-234
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe line width of the NMR signal of water protons in solutions of native actomyosin and actomyosin denatured by heat, acetone or urea was measured over the temperature range from -10° to below the freezing point. The line widths of the water band which increased exponentially with decreasing temperature were compared with each other and also with those of the corresponding control solution without actomyosin. The line broadening observed for native actomyosin solution on lowering the temperature was significantly smaller than that for heat-denatured actomyosin solution. This difference implies that this signal is sensitive to conformational perturbations of the protein. In addition, the temperature dependence of the line width for heat-, acetone-, or urea-denatured actomyosin solution was similar to that for the corresponding control solution. These phenomena can be interpreted in terms of the state of water associated with the hydrophobic and hydrophilic residues.
Similar NMR studies of actomyosin solution containing dimethyl sulfoxide (DMSO) or dimethylformamide (DMF) showed that DMSO and DMF prevent the formation of ice crystals until about -70°, suggesting that the cryoprotective effects of DMSO and DMF are due to the change in the state of water described above.
These differences in temperature dependence between the sample and control solutions are well-correlated with the viscosity of the solution. This correlation is useful for elucidation of the mechanism of the protein denaturation.View full abstractDownload PDF (479K) -
I. Novel Method for Synthesis of the Insulin-β-D-galactosidase Conjugate and Its Applicability for Insulin AssayKanefusa KATO, Yoshitaka HAMAGUCHI, Hideo FUKUI, Eiji ISHIKAWA1975 Volume 78 Issue 1 Pages 235-237
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPork insulin was subjected to mercaptosuccinylation and then coupled to β-D-galactosidase [EC 3. 2. 1. 23] from Escherichia coli using N, N'-ο-phenylenedimaleimide. The competitive binding of the conjugate and insulin to anti-insulin antibody was tested. Results showed that formation of an insulin-β-D-galactosidase conjugate could be used for immunoassay of insulin.View full abstractDownload PDF (245K) -
Masataka MORI, Masamiti TATIBANA1975 Volume 78 Issue 1 Pages 239-242
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSGlutamine-dependent carbamyl phosphate synthetase [EC 2. 7. 2. 9] was purified 1, 300-fold from rat ascites hepatoma cells (AH 13) as a multienzyme complex with aspartate transcarbamylase[EC 2. 1. 3. 2] and dihydroorotase[EC 3. 5. 2. 3], using dimethyl sulfoxide, glycerol, and dithiothreitol as stabilizers. The purified complex was essentially homogeneous on agarose-acrylamide composite gel electrophoresis and analytical ultracentrifugation. Its molecular weight was estimated to be about 870, 000 by sedimentation equilibrium studies. After alkylation with iodoacetamide or reduction with 0.6% dithiothreitol at 100°, the complex gave a single band on polyacrylamide gel electrophoresis in sodium dodecyl sulfate in a position corresponding to a molecular weight of 210, 000. These results indicate that the complex consists of four subunits of similar size.View full abstractDownload PDF (1826K) -
Naoko ARAI, Ken-ichi ARAI, Yoshito KAZIRO1975 Volume 78 Issue 1 Pages 243-246
Published: July 25, 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe interaction of the polypeptide chain elongation factor G (EF-G) from E. coli with guanine nucleotides was investigated using the hydrophobic dye, 1-anilino-8-naphthalenesulfonic acid. It was found that the fluorescence intensity of the hydrophobic dye elicited in the presence of EF-G was diminished markedly by addition of GTP, and to a lesser extent, by addition of GDP. Direct evidence for the formation of the binary complexes, EF-G•GTP and EF-G•GDP, was provided by gel filtrations of EF-G on Sephadex G-25 columns equilibrated with buffers containing radioactive GTP and GDP, respectively.View full abstractDownload PDF (332K) -
1975 Volume 78 Issue 1 Pages e1
Published: 1975
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (42K)
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