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Volume 68 (1970)
- Issue 6 Pages 763-
- Issue 5 Pages 603-
- Issue 4 Pages 427-
- Issue 3 Pages 255-
- Issue 2 Pages 137-
- Issue 1 Pages 1-
Volume 68, Issue 3
Displaying 1-17 of 17 articles from this issue
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Tsuneko UCHIDA1970 Volume 68 Issue 3 Pages 255-264
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. Antisera to RNase T1 [EC 2. 7. 7. 26] can be prepared in rabbits by two methods: either by intravenous injection of alum-precipitated antigen on alternate days for 4 weeks or by intramuscular injection of antigen with Freund's complete adjuvant followed by the second injection of free antigen after 6 weeks.
2. The immunogenicity of RNase T1 seems to be very weak. Thus, the content of antibody in the antisera obtained is less than that to RNase A [EC 2. 7. 7. 16].
3. The valence of antigen is estimated to be 4 at maximum.
4. Enzymatic activity of RNase T1 assayed with RNA is completely inhibited by binding with antibody in antibody excess. However, assaying with a small molecular weight substrate, the enzymatic activity of washed immune precipitate is about 20% as great as that of RNase T1 alone.
5. RNases T2 and U2 [EC 2. 7. 7. 17], with quite different substrate specificity from that of RNase T1, and also RNase N1, with qualitatively same specificity as that of RNase T1, have no immunological relation to RNase T1. But, RNase U1 from Ustilago sphaerogena is found to be immunologically somewhat co-related to RNase T1.View full abstractDownload PDF (2007K) -
I. Morphology of Phage Vx and Properties of Its DNANobuyoshi SHIMIZU, Kin-ichiro MIURA, Hatsuo AOKI1970 Volume 68 Issue 3 Pages 265-276
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe physical and chemical properties of Bacillus subtilis bacteriophage Vx and its DNA have been studied. This virulent phage has a large head, hexagonal outline 100mμ between opposite edges, and a long tail (170mμ) bearing a plate. Vx phage contains double-stranded DNA in 40%. The sedimentation coefficient, s020, W, of the viral DNA extracted with phenol is 55 S, and the molecular weight was calculated as 1.2_??_10_??_, daltons. Formic acid hydrolysis of purified Vx-DNA liberated four usual bases (A. T. G. C) and an unusual base (X). The total content of X and T was extremeiv low as compared with A. Enzymatic hydrolysis produced three usual mononucleotides (dpA, dpG, dpC) and one unusual mononucleotide (dpX). Phosphate analysis showed that the ratios of dpG/dpC and dpA/dpX are unity. Rf values in paper chromatography, the spectrophotometric characters and optical rotatory dispersion of dpX showed that the base X is 5-hydroxymethyluracil (HMU). It is concluded that HMU in Vx-DNA is converted partially into T and an unknown material, which does not absorb ultraviolet light, under the condition of formic acid hydrolysis. The nucleotide composition of Vx-DNA is determined as follows: dpA 28.7%, dpHMU 28.4%. dnG 21.6%, dpC 21.3%; GC content 42, 9%. In mass culture of Vx phage, a novel small phage, Nf, was induced. These two phages were clearly separated by the CsCl density gradient ultracentrifugation. The reason of occurrence of a new phage Nf was discussed, whose character will be described in the following paper.View full abstractDownload PDF (5146K) -
II. Isolation and Morphology of Phage Nf and Properties of Its DNANobuyoshi SHIMIZU, Kin-ichiro MIURA, Hatsuo AOKI1970 Volume 68 Issue 3 Pages 277-286
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe morphology of a novel Bacillus subtilis bacteriophage Nf and the physico-chemical properties of its DNA have been studied. Nf phage has an oblong head, length 43mμ and width 33mμ, with a six-sided outline and a tubular tail with similar length to the head. Numerous thin projections radiate from the head. Twelve wedge-shaped appendages are attached to the lower part of two collars. The DNA content was 40%. The preparation of DNA extracted with 0.2% sodium dodecyl sulfate contained a major component (23S) and a minor component (25S) in the sucrose density gradient centrifugation. Electron microscopic observation of Nf-DNA showed both linear and circular molecules, with a contour length of 6.4μ, which is consistent with a molecular weight of 1.2×107 daltons for the viral DNA. This molecular weight is the smallest one in DNA's of B. subtilis phages. Based upon buoyant density in CsCl and thermal denaturation, the GC content of the DNA is 39% and no satellite DNA was observed. Chemical analysis of bases showed the normal four kinds of base in DNA. The ratio of G/C and A/T was unity, and the GC content (39%) coincided with the physico-chemical measurements. Nf-DNA molecules have no single strand scission.View full abstractDownload PDF (6572K) -
Akira KOTAKI, Makoto NAOI, Kunio YAGI1970 Volume 68 Issue 3 Pages 287-292
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSFor the comprehensive characterization of the diversiform spectral data of flavoproteins, an investigation was made concerning the effect of proton donors such as trihalogenoacetic acids and phenols on the absorption spectrum of riboflavin derivative in apolar media. Spectral changes due to the interaction between the isoalloxazine nucleus of riboflavin 2', 3', 4', 5'-tetrabutyrate and these proton donors in carbon tetrachloride were characterized by the marked red shift of 340mμ absorption band (from 340 to ca. 370mμ) and the broadening of 445mμ band with its slight red shift. These changes which occur with proton donors in a moderate concentration range are accompanied by the appearance of isosbestic points, indicating that equilibrium processes are involved in the reactions. Equilibrium constants of these processes were evaluated by spectrophotometry, and the presence of hydrogen bonding in the complexing between flavin and phenols was proved by near-infrared spectrophotometry. Based on these findings, some postulations as to the interactions between flavin coenzyme and apoenzyme of some typical flavoproteins are presented.View full abstractDownload PDF (434K) -
Kunio YAGI, Makoto NAOI, Morimitsu NISHIKIMI, Akira KOTAKI1970 Volume 68 Issue 3 Pages 293-301
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe binding aspects of D-amino-acid oxidase [EC 1. 4. 3. 3, D-amino acid: oxygen oxidoreductase (deaminating)] with various carboxylic acids have been investigated in terms of changes in the absorption spectrum of its coenzyme, FAD, and in ORD and CD spectra in the wavelength range of 300-600 mμ, upon the formation of the enzyme-carboxylate complexes. Interaction of the enzyme with various inhibitor carboxylic acids seemed to involve hydrophobic bonding between alkyl group of the carboxylic acid and hydrophobic area of the enzyme. The strength of the binding is affected by the size of alkyl group of the carboxylate. This may be an indication of the local structure of the binding site of this enzyme molecule.
The results of the study on the complexes of the enzyme with aminobenzoates indicate the binding between the enzyme and the acids via a nitrogen atom close to the carboxylate group, suggesting the participation of the nitrogen lone-pair in forming the intermolecular charge-transfer complex with the enzyme.View full abstractDownload PDF (1548K) -
V. An Inspection of the Active Site of the Enzyme Utilizing Transfer ReactionKaoru OMICHI, Yoshio MATSUSHIMA1970 Volume 68 Issue 3 Pages 303-309
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. The substrate specificity of Taka-amylase A (TAA) [EC 3. 2. 1. 1, α-1, 4-glucan 4-glucanohydrolase Aspergillus oryzae] was studied utilizing transfer reaction.
2. As an acceptor in the transfer reaction were used maltitol, phenyl α-D-glucoside, phenyl α-D-glucoside, phenyl α-D-mannoside, phenyl β-D-mannoside, phenyl 2-O-methvl-α-D-glucoside, phenyl 3-O-methyl-α-D-glucoside, and phenyl 6-O-methyl-α-D-glucoside, and amylose was the substrate.
3. Of the sugar derivatives used in the experiment of transfer reaction, maltitol, phenyl α-D-glucoside, phenyl β-D-glucoside, phenyl 2-O-methyl-α-D-glucoside and phenyl 6-O-methyl-α-D-glucoside were effective as an acceptor.
4. The results obtained showed that the active site(s) of the enzyme interacts with a glucose residue situated on the aglycone side of the splitting point of the substrate molecule.View full abstractDownload PDF (2446K) -
III. Properites of Homoserine DehydrogenaseRyuichi MIYAJIMA, Isamu SHIIO1970 Volume 68 Issue 3 Pages 311-319
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSHomoserine dehydrogenase [L-Homoserine: NADP oxidoreductase, EC 1. 1. 1. 3] has been partially purified from sonic extracts of Brevibacterium flavum. Optimum pH of the reaction is 6.0; Km, values for aspartic-β-semialdehyde (ASA)* and for NADPH at pH 7.0 (potassium phosphate buffer) are 1.90×10-4M and 3.74×10-5M, respectively. Homoserine, one of the reaction products, inhibited the enzyme in the mixed manner with both ASA and NADPH, while NADP+, another reaction product, inhibited the activity non-competitively with ASA and competitively with NADPH. These results suggest an ordered mechanism for the reaction, in which NADPH is the first binding substrate and NADP+ is the last releasing product.
Homoserine dehydrogenase is strongly inhibited by the metabolic end product, threonine, in the mixed manner with both ASA and NADPH. Isoleucine weakly inhibited the activity in the competitive manner with both ASA and NADPH. Sigmoidal curves are obtained when the rate of the reaction is plotted against threonine or isoleucine concentrations. Homotropic cooperativity is shown with respect to NADPH only in the presence of these end product inhibitors. No other amino acid of aspartate family except threonine and isoleucine inhibited nor activated the activity significantly. When inorganic salts are removed from the preparation the enzyme is very labile, but it is protected by threonine from this inactivation significantly.
From above results, the role of homoserine dehydrogenase in the regulation of threonine and lysine biosynthesis is discussed.View full abstractDownload PDF (586K) -
I. Purification and PropertiesMasataka YOSHINO1970 Volume 68 Issue 3 Pages 321-329
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSAMP nucleosidase [AMP phosphoribohydrolase, EC 3. 2. 2. 4] from A. vinelandii, which hydrolyzes AMP to form adenine and ribose 5-phosphate, has been purified. The purified enzyme is homogeneous as judged by its electrophoretic behavior. The enzyme is very unstable in the absence of divalent or trivalent anions such as sulfate, succinate or citrate, which effectively stabilize the enzyme. ATP and Mg2+ are ahsolu_??_ely required for the catalytic activity of enzyme. The Km values for Mg2+ and AMP are 1×10-4M and 5×10-4M, respectively. The enzyme exhibits many of the characteristics of an allosteric enzyme. The rate-concentration curve with respect to the substrate (AMP) concentration is hyperbolic, whereas the curve with respect to ATP is sigmoidal. The enzyme activity is inhibited by GMP, IMP, phosphate, curate and NH3 in an allosteric manner. In view of these data, AMP nucleosidase may be considered as an allosteric enzyme involved in regulating the degradation and interconversion of the purine nucleotides in A. vinelandii.View full abstractDownload PDF (1230K) -
II Association and DissociationNobuaki OGASAWARA, Masataka YOSHINO, Jun'pei ASAI1970 Volume 68 Issue 3 Pages 331-340
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSAMP nucleosidase [EC 3. 2. 2. 4] purified from A. vinelandii gives an s value of 6.3 S and a molecular weight of 120, 000. Upon treatment with 1%, sodium dodecyl sulfate, the enzyme dissociates into the smaller units of molecular weight of approximately 60, 000, indicating a dimeric structure. The existence of monomer was confirmed by gel filtration and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate.
The dimeric form associates into the tetrameric form with an s value of 10.6 S and a molecular weight of 240, 000 in the presence of AMP (substrate), ATP (activator. GMP, IMP and ITP. The divalent or trivalent anions also induce the association at a high concentration (0.2M). The two forms of the enzyme (dimer and tetramer are interconvertible. The subparticle structure in the presence of AMP was clearly shown by electron microscopic study.
The 10.6 S species induced by anions and the nucleotides other than ATP are quite stable to heat denaturation, whereas the one induced by ATP is heat labile. Furthermore, in the presence of ATP, there is an evidence for a slow process of equilibrium between the 6.3 S and 10.6 S species. On the other hand, the equilibrium of these two species is rather rapid process in the presence of anions and the nucleotides other than ATP. These results suggest that the conformation of the tetramer given by ATP is somewhat different from that resulted by other nucleotides and anionsView full abstractDownload PDF (1848K) -
Yoshikazu AYAKI, Kazumi YAMASAKI1970 Volume 68 Issue 3 Pages 341-346
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS7α-Hydroxycholesterol-14C was incubated with fortified rat mitochondria and the following C24-bile acids were identified: 3β, 7α-dihydroxychol-5-enoic acid, chenodeoxycholic acid and α-muricholic acid.
From these and previous data the following new pathway of chenodeoxycholic acid biogenesis is proposed: cholesterol→7α-hydroxycholesterol→3β, 7α-dihydroxychol-5-enoic acid→ chenodeoxycholic acid.View full abstractDownload PDF (393K) -
I. Amino Acid Composition and Terminal Amino Acid AnalysisKihachiro UEHARA, Tadashi MIZOGUCHI, Shigeyasu MANNEN1970 Volume 68 Issue 3 Pages 359-367
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe amino acid composition of β-amylase [EC 3. 2. 1. 2] from sweet potatoes grown in Japan was determined. The analyses indicate that the enzyme is composed of the following 419 amino acid residues per 50, 000g of the enzyme: AsP54, Thr15, Ser18, Glu41, Pro24, Gly35, Ala34, Val31, Met13, Ile19, Leu32, Tyr18, Phe18, Lys28, His7, Arg17, Trp10, and Cys5. No disulfide bond is present in the enzyme. Discrepancies exist between the results reported here and those reported by Thoma et al. (7). All of sulfhydryl groups involved in the enzyme are relatively unreactive in the native protein.
The terminal amino acid residues were investigated. One mole of NH2-terminal alanine per 50, 000g of enzyme was found by the FDNB* method. The COOH-ter-minal amino acid was analyzed by hydrazinolysis and treatment with carboxypep-tidase A [EC 3. 4. 2. 1]. However, the results were not consistent with each other, possibly because there may be a prolyl-glycine and/or -x-proline COOH-terminal sequence in the enzyme.View full abstractDownload PDF (613K) -
I. Chemical Characterization of Lipids Bound to Native and Defatted Bovine Serum Albumin MonomersMaryvonne ROSSENEU-MOTREFF, Victor BLATON, Bernard DECLERCQ, Daniel VA ...1970 Volume 68 Issue 3 Pages 369-377
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSTwo samples of bovine serum albumin (BSA) with different lipid contents were defatted either with carbon tetrachloride or by adsorption on charcoal. Native and defatted monomers were prepared from both samples by gel filtration on Sephadex G-150 and characterized by various methods. The lipid content of the native mono-mers, as determined by thin layer chromatography, consisted of about 80% of free fatty acids and 15% phospholipids, mostly lysolecithine. Defatting removed all the phospholipids leaving about 6% free fatty acids.
The fatty acid content of the native and defatted samples was analyzed by gas liquid chromatography. Both methods of defatting reduced the fatty acid content from 1 and 2.2 mole fatty acid/mole BSA for the native samples to 0.03 mole/mole of defatted BSA. Analysis of the fatty acid distribution showed that oleic, palmitic, stearic and linoleic acids were most predominant in the native BSA samples and were most easily removed during defatting.
The mobilities of native and defatted BSA on disc polyacrylamide electrophoresis were identical.View full abstractDownload PDF (2667K) -
Hirokazu OKUDAIRA, Tateshi KATAOKA, Hidechika OKADA, Reiko FURUSE-IRIE ...1970 Volume 68 Issue 3 Pages 379-394
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSExtract prepared from mouse lymph node was found to be cytotoxic to all tested tumor cells such as MM2, Friend, SR 61, Ehrlich, S 180 and AH-66F. It also lysed the erythrocytes of sheep, guinea pig, rabbit, rat and mouse. The cytotoxic activity of the extract was enhanced in the presence of EDTA. It more efficiently lysed sheep erythrocytes at lower pH, at lower ionic strength and at higher temperature.
The cytotoxic substance termed “cellular lytic factor” (CLF) was demonstrated to be free unsaturated fatty acids. No hemolytic activity could be demonstrated in chloroform-methanol extracts prepared from lymph nodes boiled or lyophilized immediately after extirpation. Both hemolytic activity and free fatty acids appeared in parallel after homogenization. CLF was fixed on the membrane of target sheep erythrocytes and then caused cytolysis. Inhibitory activity against lymph node extract was found in normal mouse serum. The inhibitory activity was recovered in the albumin fraction. CLF inhibitor inhibited CLF activity when it was added prior to the fixation of CLF on target cells.View full abstractDownload PDF (4788K) -
Ryuichi KATO, Akira TAKANAKA, Michiko TAKAYANAGHI1970 Volume 68 Issue 3 Pages 395-413
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe effects of administration of phenobarbital and methylcholanthrene to rats on the substrate-induced spectral changes of liver microsomal P-450 were investigated.
The administration of phenobarbital increased the content of P-450 and the magnitudes of hexobarbital, aminopyrine, aniline and zoxazolamine-induced spectral changes and oxidation of the drugs by liver microsomes.
The activities to hydroxylate hexobarbital and aniline and to N-demethylate aminopyrine per the magnitudes of the substrate-induced spectral changes were decreased in microsomes isolated from phenobarbital treated rats, whereas the zoxazolamine hydroxylation activity per the magnitude of the spectral change was increased.
The administration of methylcholanthrene to male rats increased the content of P-450, whereas the magnitudes of spectral changes induced by hexobarbital and aminopyrine were decreased in accordance with the decreases in the activities of hexobarbital hydroxylation and aminopyrine N-demethylation. In contrast, the magnitudes of aniline and zoxazolamine-induced spectral changes and aniline and zrxazolamine hydroxylations were markedly increased in methylcholanthrene-treated rats.
These results suggest that the difference in the effects of methylcholanthrene is not due to the difference in the type of spectral change, but it may be related to the difference in the degree of androgen dependence in the magnitude of the spectral changes.
On the other hand, the administration of methylcholanthrene to female rats decreased the magnitudes of hexobarbital and aminopyrine-induced spectral changes, but the metabolisms of those drugs were not significantly affected.
Marked alteration in the shape of the difference spectra induced by heaoobarbitzl, aminopyrine and zoxazolamine was observed in microsomes isolated from methylcholanthrene treated rats. The administration of phenobarbital did not alter the Km and K, (spectral dissociation constant) values for the hexobarbital hydroxylation and spectral change, but increased the Km value for aniline hydroxylation.View full abstractDownload PDF (1426K) -
Tomoko HAYASHI, Koichi IWAI1970 Volume 68 Issue 3 Pages 415-417
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (147K) -
Tadashi INAGAMI, Takashi MURACHI1970 Volume 68 Issue 3 Pages 419-421
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (168K) -
Yoshinao KATSUMATA, Atsuko MIYAZI, Takayuki OZAWA1970 Volume 68 Issue 3 Pages 423-425
Published: September 25, 1970
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (165K)
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