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Volume 63 (1968)
- Issue 6 Pages 689-
- Issue 5 Pages 561-
- Issue 4 Pages 409-
- Issue 3 Pages 279-
- Issue 2 Pages 139-
- Issue 1 Pages 1-
Volume 63, Issue 4
Displaying 1-21 of 21 articles from this issue
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TSUKASA FUKUSHI, AKIRA IMANISHI, TOSHIZO ISEMURA1968 Volume 63 Issue 4 Pages 409-416
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. Changes in enzymatic activity and protein conformation during the course of regeneration of Bacillus subtilis α-amylase [EC 3.2.1.1, α-l, 4-glucan 4-glucano hydrolase] which had been denatured in acidic urea were investigated physico-chemically as well as biochemically.
2. On removing the denaturant, the enzymatic activity was recovered rapidly to 20-40% of the original activity and then gradually increased to 60-90% within 6hr. Parameters of optical rotatory dispersion and molar extinction coefficient, on the other hand, immediately reached almost the final values.
3. The amylase molecule undergoing regeneration could be readily digested with a bacterial proteinase and tended to be adsorbed on the glass surface.
4. The regeneration was inhibited by adding alcohols; their efficiency depended on the length of their hydrocarbon chain. Addition of a low concentration of detergents, such as sodium dodecylsulfate (SDS), trimethyl dodecylammonium chloride and sodium deoxycholate, also inhibited the regeneration. The inhibition by SDS was reversibly eliminated by dilution with buffer.
5. By electrophoresis on cellulose acetate membrane in the presence of SDS the denatured molecule in the course of regeneration was distinguishable from the native one.View full abstractDownload PDF (562K) -
MAKOTO SHIRASAKA, NOZOMU NAKAYAMA, AKIRA ENDO, TATSUO HANEISHI, HIROSH ...1968 Volume 63 Issue 4 Pages 417-424
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA strain of Candida krusei which could produce an exceptionally large amount of cytochrome c was selected from 300 strains of yeast and the fermentation conditions for production of cytochrome c in the cells were studied. Thiamine, glycine and α-ketoglutarate were found from the results to promote the production. By addition of thiamine and glycine to the basal medium, the cells could produce approximately 400mg of cytochrome c per kg of wet cells (approx. 70% water). It corresponds to about four fold of that produced by the cells of common baker's yeast of Saccharomyces sp. The isolation and purification of cytochrome c from the cells were achieved by means of plasmolysis of cells with ethyl acetate and column chromatography with cation exchangers, and the crystals of cytochrome c were obtained in 58% yield. The α-band maximum was found to be at 549mμ, which is shorter in wavelength than that of mammalian cytochrome c (550mμ), and the molar extinction difference between reduced and oxidized forms of this cytochrome c was 24.3×103M-1 cm-1 (549mμ), which was approximately 14% higher than that of horse heart cytochrome c. The enzymatic properties of the cytochrome c were examined with a yeast cytochrome oxidase [EC 1.9.3.1], and the results indicated that Candida cytochrome c is oxidized more than ten times faster than horse heart cytochrome c by the oxidase. Other characteristics of this cytochrome c were also described in this paper.View full abstractDownload PDF (527K) -
KOUICHI ASAMI1968 Volume 63 Issue 4 Pages 425-433
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSInhibition of the electron transport system by phenylhydrazine was studied with mitochondria and submitochondrial particles of rat liver and of beef heart. In order to obtain a maximal inhibition at a given concentration, it was needed to preincubate the particles with the inhibitor for a certain period. The appearence of inhibition required oxygen and depended on temperature. CuSO4 catalysed the autoxidation of phenylhydrazine, and completely oxidized phenylhydrazine had no inhibitory effect on the succinate oxidase system. Therefore, an intermediate in autoxidation of phenylhydrazine seemed to be the inhibitor of the electron transport system in mitochondria.
Effects of the inhibitor on each step of reaction in the succinate oxidase system and on the redox state of the cytochrome system showed that phenylhydrazine inhibits the electron transport system at a site between cytochrome b and cl, and that it destroys both cytochrome (c+c1) and a. Since the inhibition occurred without serious chemical changes of cytochromes (c+c1) and a, phenylhydrazine appeared to act primarily on a site between cytochromes b and c1 in the succinate oxidase system.View full abstractDownload PDF (622K) -
SHOKO KIJIMA, TAKAHISA OHTA, KAZUTOMO IMAHORI1968 Volume 63 Issue 4 Pages 434-445
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSTyrosyl-tRNA synthetase [EC 6.1.1.1] was purified from baker's yeast. The purified preparation had no cross reaction with 19 other amino acids. Three kinds of assay involving hydroxamate formation, ATP-PPi exchange and tyrosyl-tRNA formation were adopted to characterize the enzyme. It was observed that the Km values for tyrosine obtained with the above three methods were not the same. Among many tyrosine analogues only 3-iodo-tyrosine and D-tyrosine stimulated the ATP-PP1 exchange reaction, while tyrosol and tyramine were competitive inhibitors. Based on these results it was concluded that the hydroxyl group at the para-position and the α-amino group of the substrate have an essential role in binding to the enzyme.
The effects of several metal ions upon enzymatic activity were studied. The effects differed remarkably depending upon the assay methods.View full abstractDownload PDF (804K) -
II. Effects of Hemin and Bilirubin on Enzyme InductionNORIO HAYASHI, BINKOH YODA, GORO KIKUCHI1968 Volume 63 Issue 4 Pages 446-452
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe AIA-induced increase of ALA synthetase in rat-liver mitochondria was greatly suppressed by the administration of hemin, hemoglobin or bilirubin. The effects of bilirubin were very similar to those of hemin, suggesting that the mechanisms by which hemin and bilirubin affect enzyme synthesis may be similar, if not identical. The mitomycin-sensitive second phase of the induction appeared to be more susceptible to hemin and bilirubin than the mitomycin-insensitive first phase. Administration of hemin or bilirubin also reduced the ALA synthetase level in control rats which did not receive AIA. Evidence is presented that the observed inhibition of ALA synthetase induction might be due to inhibition of synthesis of messenger RNA. Hemin and bilirubin did not affect the increase of other AIA-inducible hepatic enzymes. The succinyl-CoA synthetase [EC 6.2.1.4] activity in liver mitochondria was not influenced by administration of hemin or bilirubin.View full abstractDownload PDF (547K) -
I. Preparation of Crystalline Cytochrome b5 from Rabbit LiverTOSHIMASA KAJIHARA, BUNJI HAGIHARA1968 Volume 63 Issue 4 Pages 453-461
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA method for purification and crystallization of cytochrome b5 from rabbit river microsomes was worked out. For solubilization of cytochrome b5 from microsomes, crystalline proteinases were used. The solubilized cytochrome was purified by treatments with CM-cellulose, DEAE-cellulose and chromatography on DEAE-Sephadex. In the case of trypsin [EC 3.4.4.4] solubilization, the cytochrome was separated into two fractions on the DEAE-Sephadex column and both were crystallized from ammonium sulfate solution. Yield of cytochrome b5 from the major fraction (the faster moving band) and from the minor fraction were about 20 and 3mg per 1kg of the liver, respectively. The former crystals were hexagonal plates and the latter were rectangular plates. In the case of solubilization by a bacterial proteinase (Nagarse), cytochrome b5 was also separated into two fractions on column chromatography and the shape of the crystals from the major fraction (the slower moving band) was hexagonal rod. The crystalline preparation of cytochrome b5 of the major fraction obtained by trypsin solubilization was ultracentrifugally and electrophoretically homogeneous. Its molecular weight was estimated to be 11, 500 from iron content. The results of elemental and amino acid analyses of the preparation are also reported.View full abstractDownload PDF (1944K) -
TADASHI YAMADA, GORO KIKUCHI1968 Volume 63 Issue 4 Pages 462-471
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSCitramalate, itaconate and some other related compounds were found to strongly inhibit the metabolism of various carboxylic acids and amino acids in Rhodopseudomonas spheroides and Rhodospirillum rubrum, while these bacteria could synthesize citramalate and itaconate. Itaconate, mesaconate and DL-methylsuccinate were more effective in the inhibition than DL-citramalate and citraconate. The itaconate concentration required to maximally inhibit the metabolism of either acetate and glutamate was as low as about 20μM. By contrast, the metabolism of succinate and fumarate was not inhibited at all by those compounds. Moreover, the 4-carbon dicarboxylic acids could release the inhibition of the matabolism of other substrates such as acetate and glutamate. The site(s) of inhibition by those compound as well as the significance of the observed inhibition in bacterial metabolism remains to be elucidated.View full abstractDownload PDF (644K) -
IKUNOSHIN KATO1968 Volume 63 Issue 4 Pages 472-478
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSWhen an aqueous solution of Taka-amylase A [EC 3.2.1.1] was placed in a sonic field, cleavage of peptide bonds occurred slightly and the reduced viscosity increased as a function of sonication time; the enzymatic activity did not change up to three hours. These phenomena indicated that the so-called active fragment of the enzyme might be present in the sonicated mixture. Purification of the fragment by chromatography on a DEAE-cellulose column and subsequent gel filtration on a Sephadex G-75 column resulted in crystallization of the active fragment. The molecular weight of the crystalline active fragment was estimated to be 37, 000 and its N-terminal group was characterized as alanine. Its amino acid composition was also determined and its enzymatic properties were compared with those of the native amylase.View full abstractDownload PDF (495K) -
IKUNOSHIN KATO, HIROKO TODA, KOZO NARITA1968 Volume 63 Issue 4 Pages 479-486
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSWhen denatured Taka-amylase A [EC 3.2.1.1], in which four disul-fide bonds had been reduced in the presence of 8M urea and EDTA and the sulfhydryl groups produced were alkylated with iodoacetate, was placed in a sonic field in the presence of calcium ion, its disordered structure was converted into a partially ordered structure, as evidenced by a decrease in reduced viscosity. In parallel to the conformational change, revival of the amylase activity was observed. The result of amino acid analysis of the reactivated amylase derivative excluded the possibility of reformation of the disulfide bonds. The measurement of optical rotatory dispersion indicated that the formation of non-α-helical structure was induced by sonic oscillation. However, the pH dependence of reduced viscosity of the reactivated amylase derivative was close to that of the intact amylase. Although it is still premature to propose a definite mechanism for such revival of the enzyme activity, a possible interpretation would be to assume the formation of an intramolecular β-structure in the enzyme derivative by sonic oscillation.View full abstractDownload PDF (1111K) -
IKUNOSHIN KATO, HIROKO TODA, KOZO NARITA1968 Volume 63 Issue 4 Pages 487-493
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSWhen the peptides derived from the tryptic digestion of the denatured Taka-amylase A [EC 3.2.1.1] were placed in a sonic field in the presence of calcium at pH 7.0, the enzyme activity revived. We have found that at least two peptides were essential to form the active aggregate by sonic oscillation. The essential two peptides could be isolated in almost homogeneous state, and their amino acid compositions were preliminarily determined. The pH optimum and the stabilities at several pH's of the active aggregate formed from the two peptides were similar to those of the native amylase. These facts seemed to suggest that the active site in the active aggregate was identical or close to identical to that of the native enzyme.View full abstractDownload PDF (428K) -
SHOSHI OTA1968 Volume 63 Issue 4 Pages 494-500
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe main proteolytically active component of the stem bromelain [EC 3.4.4.24] was autodigested at pH 4.6 and 50°C for 13hr. The hydrolysate was fractionated by elution chromatography on Amberlite CG-120 with sodium citrate buffers, and some free amino acids and peptides were isolated and identified. The results indicated that the enzyme preparation was cleaved not only at basic amino acid residues but also at other amino acid residues, especially, glycine-, alanine- and serine-residues.View full abstractDownload PDF (492K) -
MASACHIKA IRIE1968 Volume 63 Issue 4 Pages 501-505
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. Kinetic parameters, Km and Vmax, of several pancreatic ribonucleases [EC 2.7.7. 16], such as bovine, whale, porcine and horse RNases, were measured using nucleoside cyclic phosphates and dinucleoside phosphates as substrate at pH 7.0. In all the enzyme tested which have the specificity towards pyrimidine bases, an accelerating effect of the base of 3'-OH end nucleoside was observed.
2. From the Vmax values obtained, the specificity of whale RNases, Wl and W2, is found to be similar to that of RNase A, but those of porcine RNase and horse RNases, Eqt and Eq2, are found to be slightly different from that of RNase A. Horse RNases have the specificity towards uracil base than cytosine base, but porcine RNase has that towards cytosine base than uracil base in comparison with the specificity of RNase A.
3. The accelerating effect of the bases of 3'-OH end nucleoside is found to be characteristic of the each enzyme used. From this pheno-menon, it comes in question on the mechanism of pyrimidine base specific RNase A proposed by WITZEL and BARNARD.View full abstractDownload PDF (385K) -
TAKAO KOSAKA, SHINJI ISHIKAWA1968 Volume 63 Issue 4 Pages 506-513
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. Actions of piericidin A on the phosphorylating respiratory chains of mammalian mitochondria and protoplasmic membrane system of Micrococcus lysodeikticus were examined.
2. Piericidin A showed three independent actions on mammalian mitochondria. At a very low concentration (30 pmoles/mg protein), it blocked glutamate oxidation of rat liver mitochondria. At concentra-tions between I and 100μM, it uncoupled 2nd and 3rd sites of phos-phorylation and induced ATPase [EC 3.6.1.3] either in the presence or absence of Mg. At concentrations higher than 100μM, piericidin A inhibited the succinate oxidation.
3. Piericidin A inhibited the NADH oxidation catalyzed by membrane fragments of M. lysodeikticus at concentrations higher than 0.1mM. Phosphorylation of the same preparation was stimulated by piericidin A at the concentration of 0.1 mm and was inhibited by higher concentrations. Stimulation of phosphorylation by low concentrations of piericidin A was abolished by brief irradiation with near UV light of membrane fragments.
4. Mode of actions of the compound on both respiratory chains and the role of menaquinone in the respiratory chain of M. lysodeikticus have been discussed.View full abstractDownload PDF (529K) -
TAKAO SEKIYA, YASUHIRO FURUICHI, MITSUAKI YOSHIDA, TYUNOSIN UKITA1968 Volume 63 Issue 4 Pages 514-520
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe reactivity of several ribonucleosides with guanosine-2', 3' cyclic phosphate under catalysis by ribonuclease T1 [EC 2.7.7.26] was estimated and it was found that the reactivity decreased depending on the nucleoside used in the order of cytidine>uridine>inosine>adenosine.
In the similar reaction between guanosine-2', 3' cyclic phosphate and several diribonucleoside monophosphates, the largest reaction rate was observed when the diribonucleoside monophosphates containing cytidine at their 5'-end were used. The nature of nucleoside residue at 3'-end of the dinucleoside monophosphate also influenced on the reaction rate. Thus, cytidylyl-(3', 5')-cytidine was most reactive, while cytidylyl-(3', 5')-guanosine reacted very slowly.
Using this reaction, twelve triribonucleoside diphosphates, which have a guanylyl residue at their 5'-end were prepared and the products were characterized and were pure enough to use as coding triplets.View full abstractDownload PDF (1130K) -
KIYOSHI IKEDA, KOZO HAMAGUCHI, MIHOKO YAMAMOTO, TOKUJI IKENAKA1968 Volume 63 Issue 4 Pages 521-531
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe circular dichroism (CD)** and the optical rotatory dispersion (ORD) of soybean Kunitz and 1.95 trypsin inhibitors, three fractions of limabean inhibitors and ovomucoid were studied at various pH values and in 2-chloroethanol-water mixtures. Ovomucoid showed a negative Cotton effect with a trough at 230mμ in the ORD curve and negative extrema at 222 and 210mμ in the CD spectrum. This suggests that ovomucoid is a helical protein. On the other hand, soybean and limabean inhibitors showed a trough at 210mμ in the ORD curves and a negative extremum at 206mμ in the CD spectra. Thus, it was found that soybean and limabean inhibitors are nonhelical proteins. At longer wavelengths, the CD spectrum of Kunitz inhibitor gave negative bands at 294, 278 270, and 246mμ and a large positive maximum at 226mμ. 1.9S inhibitor exhibited a large negative CD maximum centered at 280mμ and a positive maximum at 234mμ with a shoulder at 245mμ. The CD spectra of limabean inhibitors also showed a negative band at 280mμ with almost the same intensity as that of 1.9S inhibitor. Limabean inhibitor, fraction I gave a positive CD maximum at 248mμ. Both fractions II and IV showed two positive CD maxima at 248 and 233mμ. Ovomucoid showed negative CD extrema at 292 and 264mμ and a positive maximum at 243mμ. The origin of these CD bands is discussed. The effects of pH and 2-chloroethanol on the CD and ORD of the inhibitors were also studied.View full abstractDownload PDF (739K) -
TSUKASA NISHIKIDO, KATSURA IZUI, AKITOSHI IWATANI, HIROHIKO KATSUKI, S ...1968 Volume 63 Issue 4 Pages 532-541
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. It was demonstrated by using 14C-bicarbonate that the CO2 fixation to the cell material was depressed by the addition of aspartate to the Escherichia coli W culture growing on the glucose-salts medium. This phenomenon was found neither due to the dilution of 14CO2 nor due to that of 14C-aspartate synthesized.
2. With cell-free extracts of this organism, a more remarkable fixation of CO2 was observed with phosphoenolpyruvate than with pyruvate. The evidence obtained suggested the involvement of phosphoenol-pyruvate carboxylase [EC 4.1.1.31] in the reaction. The reaction was activated by acetyl-CoA, or by CoA and acetyl phosphate.
3. The effect of various compounds on the CO2-fixation reaction was investigated in cell-free extracts. It was found that L-aspartate, L-malate and fumarate strongly inhibited this reaction. The inhibition by L-aspartate was observed also with a partially purified phosphoenol-pyruvate carboxylase.
4. The physiological significance of the inhibitory effect of these compounds in the growing cells was discussed from the standpoint of the control of aspartate biosynthesis and of oxaloacetate production for the maintenance of the tricarboxylic acid cycle.View full abstractDownload PDF (731K) -
EIJI KIMOTO, TAKAYO KURANARI, HIROSHI MASUDA, MUTSUYA TAKEUCHI1968 Volume 63 Issue 4 Pages 542-549
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSGlycopeptides from mucinous carcinoma of human stomach as well as normal and pathological stomach tissues without mucinous degeneration were extracted by protein digestion with papain [EC 3.4.4. 10] and trypsin [EC 3.4.4.4]. Electrophoresis in barbital buffer, pH 8.6, on cellulose acetate strips revealed that mucinous carcinoma possessed alcianophilic and PAS stainable components which migrated toward the anode slower than hyaluronic acid, although normal tissues and other pathological tissues without mucinous degeneration contained none or scarcely any.
This component was isolated by Pevikon block electrophoresis. It possessed sialic acid, fucose, galactose, glucosamine and galactosamine as major carbohydrate components. Its basophilic character was shown to be due to its relatively high sialic acid content and low content of ester sulfate groups. Thus it belonged to the group of sialomucins in epithelial mucus.
In its carbohydrate composition, except for the high fucose content, and also the abundance of threonine in the peptide moiety it was quite similar to the pseudomucin of ovarian cyst adenocarcinoma. The physical characters of the two, such as their optical rotation, viscosity and sedimentation coefficients, were also very similar.View full abstractDownload PDF (1754K) -
KATSUYA HAYASHI, TAIJI IMOTO, MASARU FUNATSU1968 Volume 63 Issue 4 Pages 550-552
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (837K) -
HARUKI YAMAGUCHI, TOKUJI IKENAKA, YOSHIO MATSUSHIMA1968 Volume 63 Issue 4 Pages 553-554
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (133K) -
TAIJIRO MATSUSHIMA, SUMIE KAWABE, TAKASHI SUGIMURA1968 Volume 63 Issue 4 Pages 555-557
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (734K) -
KUNIO YAGI, AKIRA KOTAKI, MORIMITSU NISHIKIMI1968 Volume 63 Issue 4 Pages 558-560
Published: April 25, 1968
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (185K)
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