The Journal of Biochemistry
Online ISSN : 1756-2651
Print ISSN : 0021-924X
Volume 72, Issue 1
Displaying 1-29 of 29 articles from this issue
  • II. Subunits of Sheath
    Chie YUI-FURIHATA
    1972 Volume 72 Issue 1 Pages 1-10
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
    JOURNAL FREE ACCESS
    1. The sheath of pyocin R was dissociated into subunits by treatment with 8M urea containing 0.1M Na3PO4, pH12.7, at 4°C for 2 days, or with 8M guanidine hydrochloride containing O.lM Na3PO4, pH8.4, at room temperature for 2 days, or with1% sodium dodecyl sulfate (SDS***) containing 1% β-mercaptoethanol and O.OlM phosphate, pH7.0 at 96°C for 2min. Dissociation into subunits was examined by gel filtration through Bio-Glas 500, and polyacrylamide gel electrophoresis in the presence of SDS.
    2. SDS polyacrylamide gel electrophoresis showed the presence of at least four structural components, one main and three minor components in the purified contracted sheath. The main component had a molecular weight of 35, 000 and the three minor components had those of 32, 000, 29, 000, and 26, 000. These four components differed from one another in amino acid composition. The subunit with a molecular weight of 29, 000 seemed to be a dimer of a smaller unit having a molec-ular weight of 14, 500.
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  • Minoru OTA, Nobuko SATO, Kijuro OBARA
    1972 Volume 72 Issue 1 Pages 11-20
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
    JOURNAL FREE ACCESS
    The sex differences in in vitro metabolism of testosterone in the homogenates, the microsomes or the 105, 000×g supernatant fluid of adult rat livers and the influence of estradiol-treatment or castration on the metabolism in male rats were investigated.
    In the metabolism by liver homogenates, the predominant metabolites were hydroxylated testosterones in males, whereas they were androstanedione, androsterone and 5α-dihydrotestosterone in females. Most of the substrate, testosterone, was easily metabolized in females. In the microsomes, the amount of testosterone unmetabolized remaining was high in males, while most of testosterone was metabolized to 5α-androstane-3α, 17β-diol in females. In the supernatant, a large amount of testosterone remained unchanged in females, whereas it was mainly metabolized to 5β-androstane-3α, 17β-diol in males. Castration and estradiol-treatment of male rats induced the female type of metabolic pattern to some extent.
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  • Yasuhiko KAWAMURA
    1972 Volume 72 Issue 1 Pages 21-28
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    AMP deaminase [AMP aminohydrolase, EC 3. 5. 4. 6] from chicken erythrocytes was purified using ammonium sulfate fractionation, and DEAE-cellulose and phosphocellulose chromatographies and the effects of some nucleotides and alkali metal ions on the enzyme were studied. The specific activity of the purified preparation was 140μmoles of AMP deaminated/min/mg of protein. The enzyme showed an optimal pH at 7.1 in both presence and absence of activators.
    ATP, ADP, GTP, and alkali metal ions, which are allosteric activators, protected the enzyme against heat inactivation.
    The plot of reaction rate against AMP concentration was sigmoidal in the absence of any ligands, indicating that there was a homotropic interaction between the enzyme and AMP. However, in the presence of ATP or alkali metal ions, the plot became hyperbolic, suggesting that the homotropic interaction with AMP molecules decreased. The enzyme also showed a cooperative interaction with respect to ATP. The maximal velocity of the reaction was the same in the presence and the absence of activators.
    Kinetic analysis of the cooperative interactions of the enzyme with AMP and ATP suggested that there were two binding sites for these lisrands.
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  • IV. Dissociation by DEAE-Cellulose
    Nobuo MAKINO
    1972 Volume 72 Issue 1 Pages 29-37
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    It was shown that hemocyanin from a gastropod, Dolabella auricularia was dissociated into smaller units by passing through a DEAE-cellulose column. The sedimentation coefficient of DEAE-dissociated hemocyanin fraction I, which was not adsorbed by the ion exchanger, was 15 to 19 S. Fraction I was converted by prolonged contact with the ion exchanger into fraction II, which was adsorbed by DEAE-cellulose. In fraction II, two components with sedimentation coefficients of 4 and 7 S were observed. By means of gel filtration the molecular weights of 4 and 7 S components were estimated to be 60, 000-70, 000 and 150, 000-160, 000, respectively.
    Re-association of DEAE-dissociated hemocyanin in the presence of 0.5M NaCl or 0.01M CaCl2 was investigated by means of ultracentrifugation and electron microscopy. In contrast with Dolabella hemocyanin dissociated by EDTA (1), aggregation of fraction I by CaCl2 was random and incomplete. Fraction II compponents were scarcely re-associated by the salts.
    Oxygen affinity of DEAE-dissociated hemocyanin was twice as large as that of native Dolabella hemocyanin, while n-value in Hill's equation showed only a slight decrease.
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  • II. Biosynthesis of Antigenic Proteins and Their Assembly into Pyocin Particles in Mitomycin C-induced Cells
    Tomoyuki SHINOMIYA
    1972 Volume 72 Issue 1 Pages 39-48
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    Biosynthesis of proteins of R-type pyocins, phage tail-like bacteriocins produced by Pseudomonas aeruginosa, and their assembly into pyocin particles were studied. Production of pyocins was induced with mitomycin C. Pyocin proteins appeared at 10-15min after induction and active pyocin particles appeared about lOmin later. A similar time lag, probably necessary for assembly of subunit proteins, was also observed during the exponential production of pyocin and confirmed by a pulselabelling experiment. By centrifugation on sucrose density gradient a particle with sedimentation coefficient of 41S was observed during the course of pyocin production. Some of its properties were investigated and discussed.
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  • II. Further Studies on Substrate Specificity and Mode of Action of Acid Phosphatase II
    Hiroshi YOSHIDA, Kazumi HANAMITSU
    1972 Volume 72 Issue 1 Pages 49-55
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    1. The substrate specificity of acid phosphatase II [different from EC 3. 1. 3. 2 enzyme] from Fusarium moniliforme was studied. Good substrates of the enzyme so far examined could be divided into four classes; i.e. aryl phosphates, nucleotides, phosphoenolpyruvate, and terminal pyrophosphates. Both phosphomonoesters and diesters of aryl phosphates and nucleotides were hydrolyzed.
    2. The kinetic parameters, Km and Vmax, of acid phosphatase II for p-nitrophenyl phosphate, phenyl phosphate, phosphoenolpyruvate, and inorganic pyrophosphate were determined at pH5.3. For adenosine 3'-phosphate, the upper and lower limits of the Km and Vmax values, respectively, were estimated at the same pH. The ratio, Vmax/Km, for adenosine 3'-phosphate was highest, and those for phosphoenolpyruvate and inorganic pyrophosphate were considerably lower.
    3. β-Glycerophosphate, glucose 1-phosphate, and glucose 6-phosphate were competitive inhibitors of the hydrolysis of p-nitrophenyl phosphate by acid phosphatase II.
    4. Adenosine, guanosine, and cytidine and, to lesser extents, uridine, adenine, and p-nitrophenol inhibited the hydrolysis of p-nitrophenyl phosphate by acid phosphatase II. Inhibition by adenosine was non-competitive.
    5. Acid phosphatase II can be regarded as a new enzyme because of its unique substrate specificity. The mode of action of the enzyme was discussed.
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  • Teruo MATSUBARA, Hidekazu IWASAKI
    1972 Volume 72 Issue 1 Pages 57-64
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
    JOURNAL FREE ACCESS
    Cytochrome cd of Alcaligenes faecalis, which has been found to be a nitrite reductase, was found to have a NO-reducing activity which converts NO to N2O, when ascorbate-phenazine methosulfate was used as an electron donor system. Some characteristics of the reduction of NO by cytochrome cd were examined, comparing with those by the particulate-bound NO-reductase.
    (1) The specific activity was about 500μl NO-uptake (or 250μl N2O-output)/hr/mg of cytochrome cd at pH 7 and at 10% NO in the gas phase of the reaction vessel.
    (2) The optimum pH for the reduction of NO by cytochrome cd was 5.5, which is similar to that by the particulate-bound NO-reductase.
    (3) The NO-reducing activity of the particulate-bound enzyme was inhibited by more than 20% of NO in the gas phase, while that of cytochrome cd was not saturated even at 60% of NO in the gas phase.
    (4) Effects of some inhibitors were examined upon the reduction of NO. Cyanide, azide or diethyldithiocarbamate inhibited the reduction of NO by particulate-bound NO-reductase stronger than that by cytochrome cd.
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  • Masachika IRIE, Tadashi MIYASAKA, Kiichi ARAKAWA
    1972 Volume 72 Issue 1 Pages 65-72
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
    JOURNAL FREE ACCESS
    1. The reactivity of 3-acetoxy-1-acetyl-5-methylpyrazole (AAMP) with amino and hydroxyl groups of proteins has been studied.
    2. AAMP was rather stable in an aqueous solution (pH 7.5) than N-acetylimidazole.
    3. AAMP was very reactive towards amino groups of protein at pH 7.5 and at 27 or 37°C. AAMP was also reactive towards aliphatic and phenolic hydroxyl groups of proteins, but the reaction of AAMP towards amino groups was also observed to some extent.
    4. AAMP was not so specific as N-acetylimidazole towards free tyrosyl residues of proteins.
    5. From the experiments described here, it was concluded that AAMP could be used as a novel acetylating reagent for amino groups of proteins.
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  • III. Acid Proteases in the Genus Nepenthes and Drosera peltata
    Shizuko AMAGASE
    1972 Volume 72 Issue 1 Pages 73-81
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
    JOURNAL FREE ACCESS
    Further investigations of the acid protease in the genus Nepenthes were made. Zymograms obtained by polyacrylamide-gel thin layer electrophoresis revealed that the crude secretion of Nepenthes had at least 4 protease components, whereas a purified preparation had only one. A purified preparation from an extract of Drosera peltata, which was also investigated comparing with that from Nepenthes secretion, had one protease component, which resembled the purified Nepenthes protease in electrophoretical mobility.
    Some properties of the purified protease from the extract of Drosera peltata were also investigated. With casein as a substrate the optimum pH for the enzyme action was about 3. At 40°C the enzyme was stable at pH's from 3.0 to 9.0; at 60°C it was most stable at pH 5. p-Chloromercuribenzoate and diisopropylfluorophosphate
    had no effect on the Drosera protease under the present experimental conditions.
    The substrate specificity of Drosera proteases was determined with several peptide fragments of known structure. The results showed that the enzyme preferentially splits peptide bonds at both the carboxyl and amino sides of aspartic acid residue, dominantly at the former side, at the carboxyl side of alanine, and probably at the carboxyl side of lysine.
    The present studies clearly demonstrate that the proteases in Nepenthes and Drosera peltata closely resemble each other in almost all the properties investigated.
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  • Yutaro HAYASHI
    1972 Volume 72 Issue 1 Pages 83-100
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    1. An electrophoretogram of rabbit skeletal myosin on SDS-polyacrylamide gel showed that it contains three kinds of light components with molecular weights of 25, 000 (g1), 18, 000 (g2), and 14, 000 (g3), besides f-subunit with a molecular weight of about 210, 000 (1-5). The weight ratio of the f-subunit to the g-subunit was 88: 12, indicating that one molecule of myosin (mol. wt., about 480, 000 (1, 6-8)) may contain each of the three kinds of g-subunit and the two f-subunits.
    2. Small polypeptide chains with molecular weights of less than 10, 000 were removed from S-l by treatment with alkali. After purification by combination with actin, the Mg2+-ATPase [EC 3. 6. 1. 3] activity of alkli-treated S-l was almost the same as that of intact S-l. The molecular weight of alkali-treated S-l was estimated to be 110, 000±5, 000 by osmometry and gel-filtration. S-l was separated into fractions a and b with molecular weights of about 55, 000 and 26, 000, respectively, in a weight ratio of 0.92: 1 by gel-filtration with 5M guanidine-HCl.
    3. S-l was found to consist of the five components with molecular weights of 52, 000-55, 000, 27, 000, 21, 000, 16, 000, and 14, 000 by SDS-gel electrophoresis. The weight ratio of the largest component to the others was 0.92: 1.
    4. The changes in the patterns of SDS-gel electrophoretograms were followed during digestion of myosin and HMM with trypsin [EC 3. 4. 4. 4]. The results indicated that the components with molecular weights of 52, 000-55, 000 (named the f'-component) and 27, 000 (f'') were derived from the f-subunit and the component with a molecular weight of 21, 000 was derived from g1, whereas that with a molecular weight of 16, 000 was from g2 and that with a molecular weight of 14, 000 was g3 itself.
    5. The S1-sulfhydryl group was not located on the g-subunit, but on the f-subunit. Activation of the Ca2+-ATPase activity due to blocking of the S1-sulfhydryl group was not affected by further blockage of 4.0 moles of sulfhydryl groups per 4.2×l05g of the f-subunit and 2.2 moles per 5.7×lO4g of the g-subunit with IAA.
    6. The amino acid composition of the f'-component was similar to that of the g-subunit rather than those of helical portions of the f-subunit.
    7. Based on these results, the non-identical structure of the two S-l from the bipartite heads of the myosin molecule were discussed.
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  • Kimio UMEKI, Takehiko YAMAMOTO
    1972 Volume 72 Issue 1 Pages 101-109
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    1. Of various branched dextrins formed during digestion of starch with liquefying α-amylase [EC 3. 2. 1. 1] of Bacillus subtilis, a branched dextrin consisting of six glucose units was isolated by paper chromatography and its structure was investigated, in order to obtain a clue to clarify the specificity of the amylase toward branched substrates.
    2. The isolated dextrin behaved just as a single dextrin in paper chromatography. It was, however, a mixture of singly branched dextrins of which ramifying positions ty α-l, 6-linkage were different with each other.
    3. Investigations using saccharifying α-amylase, β-amylase [EC 3. 2. 1. 2], glucoamylase [EC 3. 2. 1. 3], and pullulanase revealed that the singly branched hexaose dextrins formed by liquefying α-amylase were those having the following structures; 62-α-maltotriosylmaltotriose, 62-α-maltosylmaltotetraose, 63-α-maltosylmaltotetraose.
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  • Shosuke TAKEMURA, Shuichi HASHIMOTO, Masazumi MIYAZAKI
    1972 Volume 72 Issue 1 Pages 111-121
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
    JOURNAL FREE ACCESS
    Tyrosine transfer ribonucleic acid was purified from bulk Toruiopsis utilis tRNA by a series of chromatography on columns. The purified tRNA was digested with pancreatic ribonuclease [EC 2. 7. 7. 16] and ribonuclease T1 [EC 2. 7. 7. 26]. The endproducts were isolated by column chromatography and their nucleotide sequences were determined. Excellent separation of the RNase T1 end-products was achieved by chromatography on Dowex-1. The results of analyses of the two digests were in good agreement and indicated that the chain length of this tRNA is 78, including 18 unusual nucleotides. Overlaps of the fragments of the two sets of nuclease digestion led to 13 longer oligonucleotide sequences. These sequences gave a unique total sequence when arranged by a few common features of cloverleaf structure for tRNA
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  • Shuichi HASHIMOTO, Shosuke TAKEMURA, Masazumi MIYAZAKI
    1972 Volume 72 Issue 1 Pages 123-134
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    Several large oligonucleotide fragments obtained by partial digestion of tyrosine transfer RNA from Torulopsis utilis with ribonuclease T1 [EC 2. 7. 7. 26] were separated and their sequences were determined. The results of these analyses and those described in a preceding paper permitted the derivation of the complete primary structure of this tRNA. The established sequence was compared with those of other transfer RNAs of T. utilis and of different species for an understanding of the structural basis of functions of transfer RNA.
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  • Kunihiko IZUMI
    1972 Volume 72 Issue 1 Pages 135-140
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    The agar from Gracilaria verrucosa was separated into five fractions in a good yield by a column chromatography. Chemical analysis showed that these fractions contained increasing proportions of galactose, uronic acid, and sulfate residues and decreasing proportions of 6-O-methylgalactose and 3, 6-anhydrogalactose residues in the order of elution from the column. The sums of molar contents of the anhydrogalactose and sulfate residues in all these agar fractions amounted to approximately half the molar content of total hexose residues. By a series of similar chromatography, at least two of the acidic fractions were found to be still remarkably heterogeneous with respect to the molar ratio of uronic acid and sulfate to the anhydrogalactose residue. These findings strongly suggest that the agar is a family of polydisperse polysaccharides consisting of various intermediate molecular forms between the two extreme types of macromolecules, that is, a non-sulfated, highly methylated galactan possibly made of repeating agarobiose residues and a non-methylated, highly sulfated galactan with lesser proportion of the anhydrogalactose residue.
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  • I. Changes in Activities of Respiratory System and Lipid Peroxidation Activity
    Takashi MIURA, Tomomichi YANAGITA
    1972 Volume 72 Issue 1 Pages 141-148
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    Cells of Saccharomyces cerevisiae survived for 14 days after the cessation of growth caused by the consumption of lactate, and they began to die exponentially. In the long lasting stationary phase, respiratory activity of yeast cells decreased stepwise: the first step occurred while cells were still viable and the second step almost concomitantly with the loss of viability. The inactivations of respiratory enzymes, such as succinate-cytochrome c reductase system and cytochrome oxidase [EC 1. 9. 3. 1], started between the two impairment steps of respiration.
    The involvement of lipid peroxidation reaction in the first-step decrease in respiratory activity is suggested. The activity of this reaction, which required the presence of NADPH, increased markedly from the late log phase to the early stationary phase. In vitro experiments showed that succinate oxidase activity of yeast mitochondria was partially inactivated by lipid peroxidation system extracted from yeast.
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  • Keizo WAKU, Yasuo NAKAZAWA
    1972 Volume 72 Issue 1 Pages 149-155
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    1. 1-O-Alkyl-, 1-O-alkenyl-and 1-acyl-2-[1-14C]-linoleoyl-glycero-3-phosphorylcholine were synthesized enzymatically and submitted to hydrolyses by various phospholipases.
    2. Among the phospholipases A [EC 3. 1. 1. 4] of snake venoms, those of species of Crotalus mainly hydrolyzed diacyl compound and those of species of Naja naja hydrolyzed diacyl and l-O-alkyl-2-acyl compounds at the same rates and 1-0-alkenyl-2-acyl compound at half this rate.
    3. Phospholipase C [EC 3. 1. 4. 3] of Cl. perfringens was specific for diacyl compound while that of B. cereus hydrolyzed 1-O-alkyl-2-acyl compound three times faster than diacyl compound.
    4. Cabbage and carrot phospholipases D [EC 3. 1. 4. 4] hydrolyzed 1-O-alkyl-2-acyl compound at one third the rate of diacyl compound and l-O-alkenyl-2-acyl compound at 10% of this rate.
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  • I. Decreased131I-Insulin Degradation in the Liver of Insulin Deficient Rats
    Tetsuo UETE, Hiroko TSUCHIKURA
    1972 Volume 72 Issue 1 Pages 157-163
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    The adaptive capacity of the liver to metabolize insulin in response to the fluctuation of blood level of insulin was studied with normally fed, fasted, and alloxan diabetic rats. The degradation of insulin in the livers of fasted or alloxan diabetic rats was decreased compared with that in the livers of normally fed control rats. The hepatic proteolytic activities to hydrolyze casein, α-N-benzoyl-DL-arginine-β-naphthylamide, and L-leucyl-β-naphthylamide were not altered under the same conditions of fasting or alloxan diabetes. The rate of insulin degradation in the liver correlated well with the hepatic level of reduced glutathione. However, even when the decreased level of reduced glutathione in diabetic liver was restored to the con-trol value by the addition of crystalline reduced glutathione to the incubation mixture, the degradation of insulin did not return to the control value. On the other hand, the administration of insulin to the diabetic rats restored the decreased insulin degradation to the control level. In addition, increasing insulin concentration in incubation media (human sera) enhanced the insulin degradation in liver slices and homogenates. These findings indicate that a specific insulin degradation system is responsible for the decreased insulin degradation in insulin deficiency and the enhanced insulin degradation in increased insulin level in the body. The present study, therefore, suggests that the liver possesses an autoregulatory mechanism for
    the control of insulin degradation, the changing the rate of insulin metabolism in response to the fluctuation of the blood level of insulin. This system may operate in controlling the concentration of insulin in blood supplementary to the regulation of insulin secretion.
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  • Hirosato KIKUCHI
    1972 Volume 72 Issue 1 Pages 165-172
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    The metabolic sequence for the occurrence of an anomalous bile acid, 12-ketoehenodeoxycholic acid (12-KCCA), * found in the bile of patients with hepatobiliary diseases was disclosed.
    1. The H-l strain of Staphylococcus epidermidis isolated from the fistula bile of a patient, in which conjugated 12-KCCA was detected, showed fairly strict substrate specificity for 12α-hydroxysteroid dehydrogenation among bile acids and alcohols.
    2. Only the H-l strain had the ability to dehydrogenate cholic acid at 12-position, but a hundred strains of Staph. epidermidis collected either from nasal cavities or indoor air did not.
    3. Labeled 12-KCCA administered per os to rats remained unchanged in the intestinal cavity, while it was converted predominantly to taurocholate during the enterohepatic circulation.
    4. The 12-ketosteroid reductase was shown to be present in the rat liver homogenate and to localize predominantly in the microsomal fraction.
    5. Based on these observations, a possible metabolic sequence was presented.
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  • Takao NAKAMURA
    1972 Volume 72 Issue 1 Pages 173-177
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    A secondary liquid light standard containing luminol was calibrated at various temperatures and used to determine the photon quantum yields of some bioluminescent reactions. It was found that lOμM luminol in 0.009N NaOH emitted 1.2×1010 (±12%) quanta/ml/sec at the peak of light emission through an interference filter of peak light transmittance of 36% at 460mμ and band width of 12mμ, on reaction with 200μM ferricyanide in the presence of 4mM H2O2 at 20°C. A linear relationship was found between the peak light emission and the luminol concentration of a wide range. Convenient use of this light standard in determination of the photon quantum yields of some bioluminescent reactions is also reported and the values obtained were in reasonable agreement with those measured in other ways by previous workers.
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  • Masaru KAWAMURA, Koscak MARUYAMA
    1972 Volume 72 Issue 1 Pages 179-188
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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    The electron microscopic particle lengths of F-actin under several experimental conditions were investigated by electron microscopy.
    1. Depolymerization process of preformed F-actin was followed. When KC1 was dialyzed out from an F-actin solution in 0.1M KC1, the amount of F-actin decreased rather rapidly but the length distribution as well as the average length of remaining F-actin particles did not change significantly for as long as 24 hr of dialysis. These results suggest that the depolymerization occurs in the manner of dissociation of G-actin from the ends of F-actin.
    2. The particle length of preformed F-actin was independent on temperature below the transition temperature leading to irreversible denaturation (55 to 60°C). This finding supports the view that the ATP splitting activity of F-actin at high temperature, observed previously by Asai and Tawada, is mainly due to the intrapolymer structural changes in F-actin particles.
    3. The particle length of F-actin once polymerized at a certain high portein concentration, where the particle length of formed F-actin was shorter, was gradually increased as time elapsed after the protein concentration was lowered. β-Actinin inhibited this increase of the particle length probably due to the binding to the ends of F-actin.
    4. It was observed under the electron microscope that heavy meromyosin bound to F-actin particles fragmented them into short particles and that the extent of fragmentation was higher when heavy meromyosin was mixed with F-actin at a molar ratio of 1/3 than at the ratio of 1/1. On the other hand, Subfragment-I, the functional part of heavy meromyosin, when bound to F-actin, did not cause any changes in the electron microscopic paticle length of F-actin. These results were explained by the assumption that the structure of F-actin was loosened when both two subunits of one heavy meromyosin molecule bound to the monomers of actin in F-actin particle (s), and such fragile particles would be easily fragmented into shorter particles when treated with uranyl acetate.
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  • Tamotsu TAKETOMI, Nariko KAWAMURA
    1972 Volume 72 Issue 1 Pages 189-193
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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  • Seiichi TAKAHARA, Hitoshi TAKAHASHI
    1972 Volume 72 Issue 1 Pages 195-197
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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  • Taiju KURAMOTO, Takahiko HOSHITA
    1972 Volume 72 Issue 1 Pages 199-201
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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  • Yukio IKEHARA, Susumu YANAGI, Tomoya KAMIYA
    1972 Volume 72 Issue 1 Pages 203-205
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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  • Tomizo NIWA, Takashi TSURUOKA, Shigeharu INOUYE, Yoshihisa NAITO, Take ...
    1972 Volume 72 Issue 1 Pages 207-211
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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  • Kunihiko SAITO, Nobuko KAWASAKI
    1972 Volume 72 Issue 1 Pages 213-214
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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  • Kunio YAGI, Nobuhiko SUGIURA, Hirobumi OHAMA
    1972 Volume 72 Issue 1 Pages 215-217
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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  • Syozo TUBOI, Seiji HAYASAKA
    1972 Volume 72 Issue 1 Pages 219-222
    Published: July 25, 1972
    Released on J-STAGE: November 18, 2008
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  • 1972 Volume 72 Issue 1 Pages e1-e2
    Published: 1972
    Released on J-STAGE: November 18, 2008
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