巻号一覧
91 巻, 3 号
選択された号の論文の42件中1～42を表示しています
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Ken-ichi TANAMOTO, J. Yuzuru HOMMA1982 年 91 巻 3 号 p. 741-746
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーRegions of lipopolysaccharide derived from Pseudomonas aeruginosa essential for pyrogenicity and activation of the proclotting enzyme of the horseshoe crab were examined. Free lipid A with intact fatty acids showed strong pyrogenicity but showed little activation of the proclotting enzyme. Chemical modification of the polysaccharide portion and deacylation of the lipopolysaccharide diminished activation of the proclotting enzyme. The native-protein portion attached to the lipopolysaccharide also inhibited the activation of proclotting enzyme by lipopolysaccharide, but not pyrogenicity. These results indicate that free lipid A is sufficient for pyrogenicity, whereas the complete lipopolysaccharide is the strongest activator of the proclotting enzyme. The lipopolysaccharide of P. aeruginosa, which showed the strongest activation of proclotting enzyme, showed the weakest pyrogenicity of all the lipopolysaccharides tested here. All these results demonstrate that there is no correlation between pyrogenicity and proclotting enzyme activation induced by lipopolysaccharides.抄録全体を表示PDF形式でダウンロード (373K) -
Yuzuru ETOH, Hirofumi SHOUN, Kei ARIMA, Teruhiko BEPPU1982 年 91 巻 3 号 p. 747-753
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーMucor rennin, a milk-clotting acid protease produced by a fungus Mucor pusillus, was inactivated by photo-oxidation mediated by methylene blue according to first order kinetics. The pH profile of the inactivation rate showed that a dissociating group with a pK value of 7.6 was involved in the inactivation. Addition of pepstatin A, an inhibitor specific for acid proteases, caused a marked alkaline shift of the pK value. One of two histidyl residues in the enzyme was destroyed by the photooxidation, with complete loss of the enzyme activity. Analysis of inhibitor binding activity and chemical modification with diazoacetyl-DL-norleucine suggested that the photo-oxidized enzyme still retained its original conformation. These results indicated that one histidyl residue in addition to the two essential carboxyl groups is involved in the catalytic function of Mucor rennin.抄録全体を表示PDF形式でダウンロード (415K) -
Kaichi KIDA, Takashi NISHIO, Katsuya NAGAI, Hiroshi MATSUDA, Hachiro N ...1982 年 91 巻 3 号 p. 755-760
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe gluconeogenesis in the kidney in vivo in fed rats was studied by measuring the rate of synthesis of 14C-labeled blood glucose derived from 14C-labeled substrates injected into functionally hepatectomized rats. Among the substrates for the gluconeogenesis in the kidney examined, the most effective substrates were lactate, glycerol, pyruvate and glutamine, whose contributions to the renal gluconeogenesis were 54.0%, 26.5%, 4.1%, and 5.5% at 2:00 a. m., when the activity of phosphoenolpyruvate carboxykinase [EC 4. 1. 1. 32] was highest, and 50.0%, 31.0%, 5.3%, and 3.2% at 2:00 p. m., when it was lowest. These findings showed that there was no significant daily change in the total renal gluconeogenesis. Based on these data, we propose as a working hypothesis that a major function of the renal gluconeogenesis, utilizing lactate, glycerol, pyruvate, and glutamine as preferred substrates, is to meet the constant minimum requirement for blood glucose in the brain.抄録全体を表示PDF形式でダウンロード (343K) -
Nobuko MINAGAWA, Akio YOSHIMOTO1982 年 91 巻 3 号 p. 761-774
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーNADPH-nitrate reductase [NADPH : nitrate oxidoreductase, EC 1. 6. 6. 3] was purified 500-fold from Aspergillus nidulans with an overall yield of about 20%. The purified enzyme catalyzed NADPH-nitrate, NADPH-cytochrome c, FADH2-nitrate and reduced methyl viologen-nitrate reductase activities. Its molecular weight was estimated to be 180, 000 from the Stokes radius and sedimentation coefficient. The oxidized enzyme exhibited an absorption spectrum having a peak at 412 nm and a broad shoulder at about 450 nm. When reduced with NADPH, absorption peaks appeared at 423 (Soret), 527 (β) and 557 (α) nm, and absorption in the 450 nm region decreased. Upon treatment of the reduced enzyme with KNO3, the spectrum returned to that of the oxidized enzyme. The presence of protoheme in the enzyme was confirmed by the absorption spectrum of reduced pyridine hemochromogen. It was concluded that a b-type cytochrome (“cytochrome b-557”) is present in the enzyme and is involved in the intramolecular electron transport from NADPH to nitrate. The NADPH-nitrate and NADPH-cytochrome c reductase activities, but not the other two activities, were significantly decreased by incubation of the enzyme at 37°C in the absence of FAD. Analysis by SDS slab gel electrophoresis suggested that the nitrate reductase consists of two each of two subunits of 59, 000 and 38, 000 daltons and that a dissociation of 38, 000 subunits from the native enzyme occurs during heat treatment, resulting in alteration of the catalytic activity.抄録全体を表示PDF形式でダウンロード (1304K) -
Kunihiro YAMAMOTO, Leslie J. DEGROOT1982 年 91 巻 3 号 p. 775-782
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーA selective adsorbent for thyroid peroxidase was prepared by attaching tyrosine, a possible substrate of peroxidase, to agarose beads. When partially purified calf thyroid peroxidase was passed through a column containing this adsorbent, the peroxidase activity present was bound to the agarose. The binding of thyroid peroxidase on the adsorbent was inhibited by tyrosine and iodotyrosines. Quantitative elution was readily achieved by modifying the pH of eluting buffers. The peroxidase eluted at pH 8.5 or pH 9.8 was slowly inactivated. During this inactivation, enzyme activity assayed by triiodide formation was not affected, while peroxidase activity assayed by guaiacol oxidation and tyrosine iodination were slowly reduced. Enzyme activity was protected by elution under a partially anaerobic state. Iodide and guaiacol did not interfere with the adsorption of thyroid peroxidase by tyrosine residues on agarose.
These data indicate the following characteristics of thyroid peroxidase.
1. Tyrosine and iodotyrosines are the substrates of thyroid peroxidase.
2. Thyroid peroxidase has specific active site(s) for tyrosine and iodide which are independent of each other.
3. The active site (s) for tyrosine and iodotyrosines are common.
4. The active site (s) for tyrosine and guaiacol are similar but are not identical.
5. Thyroid peroxidase is able to bind tyrosine before it is activated to “Complex I” by hydrogen peroxide.抄録全体を表示PDF形式でダウンロード (534K) -
Ken-ichiro KOBAYASHI1982 年 91 巻 3 号 p. 783-792
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーCrithidia fasciculata, a pterin requiring protozoa, contained a NADPH-dependent dihydro-6-formylpterin reducing enzyme. The aldehyde reductase was purified and characterized. This enzyme was soluble and constitutive, and had the ability to catalyze the interconversion between aldehydes and alcohols. The optimal pH was 7.0 for the reductase activity and 9.0 for the dehydrogenase activity. The enzyme had a broad substrate specificity and reduced aromatic and aliphatic aldehydes such as dihydro-6-formylpterin, benzaldehyde, pyridine-3-aldehyde, butyraldehyde, DL-glyceraldehyde, and acetaldehyde. The enzyme was inhibited by sulfhydryl reagents and heavy metals, but not inhibited by chelating reagents. Its molecular weight was determined to be 66, 000 and 72, 000 by gel filtration and sedimentation equilibrium analysis, respectively. The value of 39, 000 was obtained by sodium dodecyl sulfate gel electrophoresis indicating a dimeric structure. The aldehyde reductase of Crithidia may be classified as NADP+-dependent aryl-alcohol dehydrogenase [EC 1. 1. 1. 91].抄録全体を表示PDF形式でダウンロード (1432K) -
Tadaomi TAKENAWA, Yoshitaka NAGAI1982 年 91 巻 3 号 p. 793-799
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーCDP-diglyceride: inositol transferase was inhibited by unsaturated fatty acids. The inhibitory activity decreased in the following order: arachidonic acid>linolenic acid>linoleie acid>oleic acid_??_palmitoleic acid. Saturated fatty acids such as myristic acid, palmitic acid, and stearic acid had no effect. Calcium ion also inhibited the activity of CDP-diglyceride: inositol transferase.
In rat hepatocytes, arachidonic acid inhibited 32P incorporation into phosphatidylinositol and phosphatidic acid without any significant effect on 32P incorporation into phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine. Ca2+ ionophore A 23187 also inhibited 32P incorporation into phosphatidylinositol. However, 32P incorporation into phosphatidic acid was stimulated with Ca2+ ionophore A 23187.
Phosphatidylinositol-specific phospholipase C was activated by unsaturated fatty acids. Polyunsaturated fatty acids such as arachidonic acid and linolenic acid had a stronger effect than di- and monounsaturated fatty acids. Saturated fatty acids had no effect on the phospholipase C activity. The phospholipase C required Ca 2- for activity. Arachidonic acid and Ca2+ had synergistic effects.
These results suggest the reciprocal regulation of phosphatidylinositol synthesis and breakdown by unsaturated fatty acids and Ca2+.抄録全体を表示PDF形式でダウンロード (455K) -
Yumiko KAWABATA, Fumio TASHIRO, Yoshio UENO1982 年 91 巻 3 号 p. 801-808
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーZearalenone and its derivatives (α-zearalenol and α-zearalanol), estrogenic mycotoxins produced by Fusarium species, when added in vivo and in vitro to immature rat uteri, induced the incorporation of labeled amino acids into a specific uterine protein (induced protein). When immature rat uteri were incubated with α-zearalenol in vitro, the maximum induction of the induced protein synthesis was obtained with 1×10-6M and the induction was detected 15min after the start of the incubation. Moreover, this induction was strongly inhibited by prior addition of inhibitors of RNA synthesis such as α-amanitin and actinomycin D. The molecular weight of the induced protein obtained by the in vivo and in vitro treatments with zearalenone and α-zearalenol was estimated to be about 52, 000 by means of SDS-polyacrylamide gel electrophoresis.
These findings clearly indicate that these estrogenic mycotoxins, despite their non-steroidal structures, exhibit an estrogenic activity toward target tissues in a similar manner to that of natural estrogens.抄録全体を表示PDF形式でダウンロード (465K) -
Noshi MINAMIURA, Koji MATOBA, Hiroshi NISHINAKA, Takehiko YAMAMOTO1982 年 91 巻 3 号 p. 809-816
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーα-Glucosidase was extracted from a homogenate of human kidney, initially with 0.02M Tris-HCl buffer, pH 7.6, and subsequently with a mixture of 0.5% cholate and 0.5%. Triton X-100 in the same buffer, pH 7.6. The enzyme in each of these two fractions was purified to the electrophoretically pure state by fractional precipitation with ammonium sulfate, column chromatographies on DEAF-cellulose, hydroxyapatite, Bin Gel A-1.5m and affinity chromatography on heated glutinous rice. The two purified α-glucosidase preparations obtained were the same in enzymatic and proteochemical properties, and the molecular weight and isoelectric point estimated were 3×105 and 4.2, respectively. No evidence for subunit structure was obtained. The optimum pH for activity was 5.6 and the activity was drastically inhibited by Nojirimycin. The α-glucosidase readily hydrolyzed maltose, starch, and glycogen, producing only glucose. It hydrolyzed maltotriitol to spilit the nonreducing end glucose, but scarcely hydrolyzed maltitol or various other heteroglucosides examined. All these proteochemical and enzymatic properties of kidney α-glucosidase were the same as those of urine F-1 α-glucosidase. Also, kidney tissue α-glucosidase produced a clear precipitin line with antisera against urine F-1 α-glucosidase. These facts suggest that F-1 α-glucosidase in urine originates from kidney tissue.抄録全体を表示PDF形式でダウンロード (949K) -
Takashi KUMAZAKI, Shin-ichi ISHII1982 年 91 巻 3 号 p. 817-823
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーA simple photometric method for rapid and accurate determination of the activity of pyocin R 1, a bacteriocin produced by Pseudomonas aeruginosa strain P 15, has been developed. This method is based on the turbidity-decrease observed when the bacteriocin is added to a suspension of sensitive bacteria P. aeruginosa strain P 11. Optimum conditions for the turbidity-decreasing activity of pyocin R 1 are in 0.01M Tris-HCl buffer containing 0.2M NaCl (pH 7.5) at 37°C. A good correlation was found between the dose of pyocin R 1 and the rate of the turbidity-decrease (with a correlation coefficient of more than 0.98). The amount of pyocin R 1 required for this assay is nearly the same as that used for the conventional colony-counts method. The assay for one sample takes less than 3min, whereas an overnight wait is necessary for the conventional method. This method is shown to be very suitable for following the time course of activity change observed when pyocin R 1 is treated with various chemicals, including receptor substances obtained from sensitive cells. The turbidity-decrease assay was also found to be applicable to the determination of activities of other R-type pyocins.抄録全体を表示PDF形式でダウンロード (446K) -
Takashi KUMAZAKI, Yasuhiko OGURA, Shin-ichi ISHII1982 年 91 巻 3 号 p. 825-835
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーBy a mild alkaline treatment, pyocin R 1 was disassembled into its structural parts, a contracted sheath (and its fragments), a core, and fibers. An alkaline sucrose density gradient centrifugation after this treatment was effective in obtaining fiberrich fractions. The pooled fractions were treated with IgGs against isolated sheaths and isolated cores, simultaneously, and then chromatographed on DEAE-Sepharose CL-6 B. The final preparation of fibers purified in this way was confirmed to be homogeneous by electron microscopic observation and an immuno-precipitation reaction. The isolated fiber was found to consist of two major subunit proteins, No. 2 and No. 9, with molecular weights of 71, 000 and 31, 000, respectively. The fiber exhibited the ability to be adsorbed on sensitive bacterial cells (Pseudomonas aeruginosa P 14), and to protect against the inactivation of pyocin R1 by a lipopolysaccharide preparation from the bacteria.抄録全体を表示PDF形式でダウンロード (2471K) -
Retsu MIURA, Yasuzo NISHINA, Kiyoshi SHIGA, Hiromasa TOJO, Hiroshi WAT ...1982 年 91 巻 3 号 p. 837-843
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーResonance Raman (RR) spectra of two reaction intermediates of D-amino acid oxidase with substrate analogs were obtained. The reaction intermediates studied were (1) the one in the aerobic oxidative reaction of the enzyme with β-cyano-D-alanine and (2) the other in the reverse reductive reaction of the enzyme with chloropyruvate and ammonium. Both intermediates are characterized with the charge transfer absorption bands in the long wavelength region extending beyond 600 nm. The RR spectra of the two intermediates excited at 488.0 or 514.5 nm are those of oxidized flavin, which is consistent with our previous assumption that oxidized flavin is involved in these reaction intermediates. Relatively simple RR spectra were obtained for these intermediates with excitation at 632.8 nm which is within the region of the charge transfer bands. The resonance enhancement for the Raman lines around 1585 and 1350 cm-1 for either of the intermediates with excitation in the region of the charge transfer bands suggests that the charge transfer interaction involves the N (5)-C (4 a) region extending to the C (10 a)-N (1)-C (2) region of the isoalloxazine nucleus. The Raman line at 1657 cm-1 for the intermediate with chloropyruvate and ammonium was assigned to C=N of an imino acid from the isotopic frequency shift upon 15N-substitution. This assignment substantiates our previous conclusion that the intermediate involves an imino acid, α-imino-β-chloropropionate.抄録全体を表示PDF形式でダウンロード (411K) -
Akira SAKAI, Yoshio WATANABE1982 年 91 巻 3 号 p. 845-853
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーTwo DNA polymerase activities, polymerases A and B, were separated from the Triton-treated cell homogenate of exponentially growing Tetrahymena pyriformis by phosphocellulose column chromatography. Their properties were as follows. Polymerase A: The molecular weight was about 140, 000, the sedimentation value was about 6.2 S, the optimum Mg2+ concentration was 15mM, the optimum K+ (or Na+) concentration was 20mM, and the optimum pH was 7.4. The enzyme activity was inhibited by cytosine-β-D-arabinofuranoside-5'-triphosphate (araCTP) or aphidicolin, but not by 2'-3'-dideoxythymidine-5'-triphosphate (ddTTP). Polymerase B: The molecular weight was about 70, 000, the sedimentation value was 4.3 S, the optimum Mg2+ concentration was 15mM, the optimum K+ (or Na+) concentration was 150mM, and the optimum pH was 8.4. The enzyme activity was inhibited by ddTTP, but not by araCTP or aphidicolin. Polymerases A and B were both found to be N-ethylmaleimide-sensitive.
These results indicate that at least two N-ethylmaleimide-sensitive DNA polymerases, A and B, are present in exponentially growing Tetrahymena cells. Polymerase A bears many similarities to DNA polymerase α of higher eukaryotes and polymerase B also bears similarities to DNA polymerase β except as regards N-ethylmaleimide sensitivity. Based on the properties of polymerases A and B, the relation of Tetrahymena DNA polymerases reported by several investigators is discussed.抄録全体を表示PDF形式でダウンロード (550K) -
Akira SAKAI, Yoshio WATANABE1982 年 91 巻 3 号 p. 855-863
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーWe investigated the relation between two N-ethylmaleimide (NEM)-sensitive DNA polymerases (designated as pol A and pol B in the preceding paper) and an NEM-resistant DNA polymerase (Furukawa et al. (1979) Nucl. Acids. Res. 7, 2387-2395) of Tetrahymena pyriformis with respect to changes in activity during cell growth and to chromatographic properties. Pol A activity per culture increased in accordance with the increase in cell number during the log phase but decreased during the stationary phase. Pol B and NEM-resistant polymerase activities per culture also increased during the log phase and the increases continued even in the stationary phase. All the changes were protein synthesis-dependent, since the changes were inhibited by treating the cells with cycloheximide. The changes of pol B and NEM-resistant polymerase activities during cell growth were always parallel and the ratio of the two enzymatic activities (NEM-resistant polymerase activity/pol B activity) remained constant with a value of about 0.03. This was also the case for cycloheximide-treated cultures. Furthermore, the enzymatic activities could not be separated by successive column chromatographies on phosphocellulose, DEAF-Sephadex A-25 and thiol-Sepharose. In these chromatographies, the elution profiles of the two activities coincided with each other and the activity ratio kept a constant value of about 0.03.
From these results, it is likely that the apparent NEM-resistant activity we measured corresponds to the remaining activity of pol B under NEM inhibition; in other words, no NEM-resistant polymerase really exists in Tetrahymena.抄録全体を表示PDF形式でダウンロード (524K) -
Ikuo KAWASHIMA, Kayoko FUKUDA, Motowo TOMITA, Akira HAMADA1982 年 91 巻 3 号 p. 865-872
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe oligosaccharide units of glycophorin isolated from porcine erythrocyte membranes were released by alkaline borohydride treatment and purified by gel filtration and ion-exchange chromatography. Structures of the O-glycosidic oligosaccharides were determined by methylation analysis, the methylated sugar being identified by gas-liquid chromatography-mass spectrometry and nitrous acid deamination after hydrazinolysis. The major oligosaccharide was a trisaccharide, Gal (1→3) [NeuNGly (2→6)] GalNAc. The other oligosaccharides were larger and contained GlcNAc. One was a pentasaccharide, Gal (1→3) Gal (1→4) GleNAc (1→3) Gal (1→3) GalNAc. The structure of the trisaccharide was also analyzed by direct-probe mass spectrometry of the permethylated derivative, and the result obtained was consistent with the proposed structure.抄録全体を表示PDF形式でダウンロード (539K) -
Noriko ANDO, Tamio YAMAKAWA1982 年 91 巻 3 号 p. 873-881
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーSeven ganglioside species were isolated and purified from erythrocyte membranes of Japanese cats by DEAE-Sephadex and latrobeads column chromatographies. The structures of these gangliosides were determined as GM 1 (NeuGc), GM 3 (NeuAc), GM 3 (NeuGc), GD 3 (NeuGc), GD 3 (NeuGc←NeuAc), GT 3 (NeuGc), and another GM 3 containing a sialic acid of unidentified nature. The occurrence of GT 3 suggested the probable presence of a biosynthetic pathway of GM 3GD 3→GT 3 in erythropoietic cells of Japanese cats. The presence of GD 3 having one penultimate N-glycolylneuraminic acid and one terminal N-acetylneuraminic acid, GD 3 (NeuGc←NeuAc) would indicate that this GD 3 acts as an intermediate in a possible pathway from GM 3 (NeuGc) to GD 3 (NeuGc).
Thin layer chromatographic patterns of toal erythrocyte membrane gangliosides were compared among Japanese cats (n=3), lions (n=3), a serval and a racoon dog. The three species of felid showed similar patterns to each other and contained N-glycolylneuraminic acid as the major sialic acid. On the other hand, erythrocytes of racoon dog, a member of canidae, contained neither GD3 nor GT3, but only GM3.抄録全体を表示PDF形式でダウンロード (2790K) -
Takaomi TAIRA, Ryuken KII, Kuniyasu SAKAI, Hikaru TABUCHI, Saeko TAKIM ...1982 年 91 巻 3 号 p. 883-888
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーGlycogen phosphorylase kinases in soluble fractions of various rat tissues were examined for the pH 6.8/8.5 activity ratio, Ca2+dependency, activation by cyclic AMP-dependent protein kinase (protein kinase A), and reactivity with anti-skeletal muscle phosphorylase kinase serum. The enzymes could be divided into at least two major groups; muscle and liver types. The muscle type, that has a low value of pH 6.8/8.5 activity ratio, is highly dependent on Ca2+, markedly activated by protein kinase A, and strongly inhibited by the antiserum. Inversely, the liver type, that has a high value of pH 6.8/8.5 activity ratio, is poorly dependent on Ca2+, not activated by protein kinase A, and weakly inhibited by the antiserum. The enzymes from heart and skeletal muscle were similar and belonged to the former entity. Whereas, the enzymes from liver, kidney, spleen, lung, and testis appeared to belong to the latter entity. The enzyme from brain apparently differs from these entities, and seems to be an intermediate type or a hybrid of the two.抄録全体を表示PDF形式でダウンロード (394K) -
Masa-aki TAKAHASHI, Kozi ASADA1982 年 91 巻 3 号 p. 889-896
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーPulse-generation of O2- by a flash was used to determine the reactivity of O2-. O2- was produced within 10 ms by a flash of light through the excitation of FMN in the presence of N, N, N', N'-tetramethylethylenediamine and oxygen. Kinetic analysis of cytochrome c reduction by O2- generated by flash yielded the reaction rate constant between cytochrome c and O2- and the spontaneous disproportionation rate constant of O2-. We applied it for superoxide dismutase assay using a linear relation between superoxide dismutase concentration and the apparent rate constant of cytochrome c reduction by O2-. The catalytic rate constant and activation energy at pH 7.3 of bovine liver Cu, Zn-superoxide dismutase were found to be 1.75×109 M-1•s-1 at 25°C and 26.9 kJ•M-1, respectively.
The kinetics of O2- decay can be also monitored at 240 nm in this flash-photometric system and gave the spontaneous disproportionation rate constant of O2- and the catalytic rate constant of superoxide dismutase.抄録全体を表示PDF形式でダウンロード (505K) -
Minoru NOMOTO, Hiroaki HAYASHI, Koichi IWAI1982 年 91 巻 3 号 p. 897-904
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe complete amino acid sequence of Tetrahymena pyriformis H 2 B histone was determined. The histone was obtained as described in the preceding paper [Nomoto, M. & Iwai, K. (1982) J. Biochem. 91, 719-723]. The purified histone was digested with an arginine-specific protease, clostripain, and the peptides, fragmented at 7 arginyl bonds and also at many of the 20 lysyl bonds, were fractionated by repeating column chromatography; most of these peptides were sequenced by Edman degradation. The chymotryptic peptides overlapping the clostripain peptides were obtained by limited or more extensive digestion of intact histone. The sequencing of these peptides led to reasonable aligning of the clostripain peptides. Thus, the sequence of 119 amino acid residues (mol. wt. 13, 316 for the unmodified form) has a completely α-N-blocked proline at residue 1 and a partially ε-N-acetylated lysine at residue 3. This sequence is compared with the known sequences of calf thymus and other H2B histones, and the implications for the structure and function relationship of this histone species and also for the phylogeny of protozoa are discussed.抄録全体を表示PDF形式でダウンロード (455K) -
Isao MORISHIMA1982 年 91 巻 3 号 p. 905-909
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーGuanosine 3'-phosphate and 2'-deoxyguanosine 3'-phosphate are potent inhibitors of guanylate cyclase of various tissues of the silkworm, Bombyx mori. The inhibitory activity is specific for guanine 3'-nucleotides. Thus, 2'-GMP and 5'-GMP are one order or more less potent than 3'-GMP, and the other 3'-nucleotides except 3'-IMP, i.e. 3'-AMP, 2'-deoxy-3'-AMP, 3'-CMP, and 3'-TMP, have no inhibitory activity. Guanosine and 2'-deoxyguanosine are only weakly active. The 3'-nucleotide inhibition is dependent on the concentration of Mn2+. The concentrations of 2'-deoxy-3'-GMP and 3'-GMP required for 50'% inhibition are 0.12 and 0.15mM, respectively, with 5mM Mn2+.抄録全体を表示PDF形式でダウンロード (273K) -
Hiroshi TAKATSUJI, Tokuzo NISHINO, Katsura IZUI, Hirohiko KATSUKI1982 年 91 巻 3 号 p. 911-921
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーWhen microsomal fraction of Saccharomyces cerevisiae was incubated with farnesyl pyrophosphate or presqualene pyrophosphate in the presence of Mn2+, 12, 13-cisdehydrosqualene (DeH2Sq) and some related compounds were found to be formed. Incubation in the presence of NADPH gave rise to only squalene. By heat treatment of the microsomal fraction, the DeH2Sq- and squalene-forming activities were inactivated at approximately the same rate. The elution patterns of both activities upon Sephacryl S-200 chromatography of the enzyme solubilized from the microsomal fraction with taurodeoxycholate coincided completely. These results indicate that DeH2Sq formation in yeast is catalyzed by squalene synthetase. Divalent cation was essential for this reaction and Mn2+ was six times more effective than Mg2-. DeH2Sq formation was also observed when microsomes of pig liver were used instead of yeast microsomal fraction, suggesting that this reaction is a ubiquitous one among the eucaryotes which are capable of synthesizing sterols. Based on these observations, the mechanisms of DeH2Sq and squalene formations are discussed.抄録全体を表示PDF形式でダウンロード (753K) -
Yasunori KUSHI, Shizuo HANDA1982 年 91 巻 3 号 p. 923-931
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーSimple molecular species of intact ceramide mono-, di-, tri-, tetra-, and pentasaccharides purified by reversed phase high-performance liquid chromatography (HPLC) were analyzed by field desorption mass spectrometry (FD-MS). The analysis of sphingoglycolipids without chemical derivatization by FD-MS not only provides molecular information but also significant characteristic fragments for structural determination due to the cleavage of glycosidic bonds. These ions, therefore, give information on the molecular species of sphingoglycolipids and sugar sequences of their oligosaccharides.
Intact GL1a, GL2a, and an equimolar mixture of GL1a and GL2a were also analyzed by FD-MS. In the spectra, the ions, (M+H)+, (M+Na)+, and (M+H-H2O)+, were observed as high intensive ions and different molecular species ions thereafter could be identified in all spectra.
The FD-MS method is particularly useful in structural studies of glycolipids from natural sources.抄録全体を表示PDF形式でダウンロード (498K) -
Hiroshi TERAOKA, Hitoshi ARITA, Mikio TAMAKI, Yoko FUJII, Kentaro TANA ...1982 年 91 巻 3 号 p. 933-938
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーMicroinjection of mouse liver mRNA into Xenopus laevis oocytes induced efficient export of a polypeptide with an apparent Mr of 68, 000 which was immunoprecipitable with anti-mouse albumin antibody. Analysis of the anti-albumin precipitate of the exported protein by two-dimensional gel electrophoresis showed that the electrophoretic behavior precisely coincided with that of authentic mouse serum albumin. This result indicates that the Xenopus oocyte may perform secretory processes similar or identical to those occurring in liver cells with respect to the processing of albumin.抄録全体を表示PDF形式でダウンロード (2128K) -
Masayuki KANDA, Kazuko HORI, Toshitsugu KUROTSU, Yoko YAMADA, Setsuko ...1982 年 91 巻 3 号 p. 939-943
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーPhenylalanine activation of gramicidin S synthetase 1 (GS 1) [EC 5. 1. 1. 11] of Bacillus brevis is inhibited by phenylglyoxal. The inactivation of GS 1 by phenylglyoxal obeys pseudo-first-order kinetics and formation of a reversible enzyme-reagent complex prior to modification is indicated. Both ATP and phenylalanine prevent the inactivation by phenylglyoxal. ATP is competitive with phenylglyoxal, whereas phenylalanine is not. In the presence of ATP, one residue of arginine per mol of protein is protected from the modification as determined by amino acid analysis and incorporation of [7-14C] phenylglyoxal. These results indicate that a single arginine residue of GS 1 is essential for phenylalanine activation in binding the phosphate moiety of ATP.抄録全体を表示PDF形式でダウンロード (319K) -
Akiko JIMBO, Isamu MATSUMOTO1982 年 91 巻 3 号 p. 945-951
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe role of a tyrosyl residue in the binding of Arachis hypogaea (peanut) agglutinin, AHA, to lactose has been studied using two techniques, titration of the phenolic hydroxyl group of the tyrosine residue and chemical modification of the tyrosine with iodine.
More than three tyrosyl residues per mol of AHA were masked when AHA was titrated in the presence of lactose. Lactose also protected some tyrosyl residues of AHA from the modification with iodine. Upon interaction with lactose, AHA iodinated in the presence of lactose gave a UV-difference spectrum with similar peaks to those of native AHA, while AHA iodinated in the absence of lactose gave a spectrum without such peaks. Though not only native AHA but also iodinated AHA was completely adsorbed on a column of lactamyl-Sepharose 6 B, equilibrium dialysis showed that the binding constant and the number of binding sites of native AHA and iodinated AHA with lactose were 4.3×103 and 3.0×103M-1, and 3.2 and 1.8, respectively.
These results suggest that about two of four sugar binding sites have tyrosyl residues which induce the UV-difference spectra upon binding with lactose, and that the iodination of these tyrosyl residues results in a decrease of the number of binding sites on AHA.抄録全体を表示PDF形式でダウンロード (414K) -
Masateru SHIN, Naoko SAKIHAMA, Nobuko SUGIMOTO, Tomoaki MIYAZAWA, Reik ...1982 年 91 巻 3 号 p. 953-957
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーImmobilized ferredoxin-NADP+ reductase (FNR) was prepared by coupling reaction of CNBr-Sepharose 4 B with the spinach enzyme. The immobilized FNR was found to retain the activity of complex formation with ferredoxin as well as the enzymatic activities such as NADPH-diaphorase and NADPH-cytochrome c reductase activities. The complex formation of immobilized FNR with ferredoxin was investigated by measuring reflex spectra of the immobilized FNR with or without ferredoxin and by titration with ferredoxin. The experimental results obtained for the dissociation constant, pH profile and effect of salts were coincidental with those reported for the free enzyme system.抄録全体を表示PDF形式でダウンロード (290K) -
Seiichi KAWASHIMA, Kazutomo IMAHORI1982 年 91 巻 3 号 p. 959-966
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe core proteins dissociated from chicken erythrocyte chromatin in high salt and at various pHs were characterized according to their histone composition and the oligomeric degree of histones. The dissociation profile of histones from chromatin by salt was also examined.
The type of histone oligomers formed depended on pH during dissociation and fractionation. Heterotype histone oligomers were obtained at pH 6-9, while the octamer dissociated into homotype histone oligomers at pH 4-5. At pH 8, the octamer was in an equilibrium with the (H 2 A•H 2 B) (H 3•H 4)2 hexamer, the (H 3•H 4)2 tetramer, and the (H 2 A•H 2 B) dimer. At pH 5, the octamer dissociated into homotype dimers, presumably (H 2 A•H 2 B) and (H 3•H 4).抄録全体を表示PDF形式でダウンロード (2151K) -
Seiichi KAWASHIMA, Kazutomo IMAHORI1982 年 91 巻 3 号 p. 967-973
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーChicken erythrocyte chromatin, whole or (H 1, H 5)-depleted, was dissociated in 2M NaCl in the presence or absence of 5M urea at pH 8 or pH 5, and reconstituted by decreasing the concentration of NaCl and urea. The reassociated products were characterized by their solubilities in 0.1mM EDTA, micrococcal nuclease digestion, cross-linking of histones, and fractionation of histone oligomers by solubility in ammonium sulfate solution.
In the absence of urea, the nucleosome structure and the histone octamer were reconstituted perfectly at both pH 5 and pH 8. When chromatin was exposed to urea, no nucleosome structure or histone octamer was obtained at pH 5 either decreasing the concentration of salt first or that of urea first. At pH 8, the chromatin structure was regained fairly well by decreasing the concentration of urea first, but only partially by decreasing the concentration of salt first. Solubility in 0.1mM EDTA was found to be a good criterion for monitoring the proper reassociation of chromatin.抄録全体を表示PDF形式でダウンロード (1835K) -
Kiyoshi IWAMOTO, Junzo SUNAMOTO1982 年 91 巻 3 号 p. 975-979
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーUnder specific conditions where neither induced aggregation nor fusion is brought about, the adsorption of polysaccharides on liposomal membranes was investigated by the fluorescence depolarization technique using fluoresceinylthiocarbamoyldextrans (FITC-dex) as probes.
The adsorption of FITC-dex on liposomes significantly increased the fluorescence polarization of FITC fluorophore due to the restriction of the mobility of the dextrans. Dextran with larger molecular weight was efficiently adsorbed on liposomes, in good agreement with the tendency for polysaccharide-induced aggregation of liposomes (Sunamoto et al. (1980) J. Biochem. 88, 1219-1226). The adsorption seemed to be related to the fluidity of liposomal membranes, since dextrans were adsorbed more efficiently on egg lecithin liposomes than dipalmitoyl lecithin liposomes at 25.0°C. However, the adsorption of dextrans did not cause a significant change in the fluidity of the liposomal membrane itself under the specific conditions adopted in this work; this was ascertained from the mobility of sodium 8-anilino-1-naphthalenesulfonate (ANS) intercalated close to the surface of liposomes.抄録全体を表示PDF形式でダウンロード (316K) -
Fumie YAMASAKI, Hidenori HAYASHI1982 年 91 巻 3 号 p. 981-988
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe kinetic properties and susceptibilities to various agents of intracellular (particulate and soluble) and extracellular phosphodiesterases [EC 3. 1. 4. 17] of Dictyostelium discoideum induced by cyclic adenosine 3', 5'-monophosphate (cyclic AMP) were studied and compared. Intracellular particulate phosphodiesterase was obtained by solubilization of the light mitochondrial fraction with Emulgen. The Michaelis constants of this enzyme were 4.5±0.7 and 10±0.7 μM, while those of the intracellular soluble phosphodiesterase were 4.6±0.3 and 13±2.8 μM. However, the Michaelis constant of the extracellular phosphodiesterase was 6.8±0.9 μM, differing from the values of the two intracellular enzymes. Susceptibilities of the enzyme activity to various agents (theophylline, caffeine, dithiothreitol, glutathione, etc.) were essentially the same among these three phosphodiesterases. In the presence of 10mM ethylenediaminetetraacetate, the activities of the particulate and the soluble enzymes were both decreased to about 60%, while that of the extracellular enzyme remained at 90%. The inhibition constants of cyclic inosine monophosphate for the cellular enzymes (35 and 100 μM for the particulate enzyme, and 37 and 90 μM for the soluble one) were considerably different from the value for the extracellular enzyme (48 μm).
These results suggest that the characteristics of these three phosphodiesterases are substantially similar, but that the affinity of the intracellular (particulate and soluble) enzymes for the substrate is somewhat different from that of the extracellular enzyme.抄録全体を表示PDF形式でダウンロード (513K) -
Masayuki MIYAWAKI, Sumio TANASE, Yoshimasa MORINO1982 年 91 巻 3 号 p. 989-999
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーReaction of the pyridoxal form of cytosolic aspartate aminotransferase from pig heart with 1, 2-cyclohexanedione or other α-dicarbonyls led to a progressive decrease in the enzymic activity toward natural dicarboxylic substrates. The inactivation was prevented by the presence of dicarboxylic substrate analogs. The dependence of the inactivation rate on the cyclohexanedione concentration indicated that the modifying reagent forms a dissociable complex with the enzyme prior to the inactivation. These saturation kinetics were observed also with other α-dicarbonyls tested. The inactivation was fully accounted for by the modification of a single arginine residue per monomeric unit of the enzyme. Activities for α, β-elimination reaction with 3-chloro-L-alanine and transamination with L-alanine did not decrease but appeared to increase considerably with the progress of the arginine modification. In these aberrant reactions, affinity for the monocarboxylic substrates was higher with the modified enzyme than with the native unmodified enzyme. Glutamate or aspartate was still capable of reacting with the pyridoxal form of the extensively modified enzyme to produce the pyridoxamine form at a rate comparable to that of the reaction with 3-chloro-L-alanine or L-alanine. Succinate, glutarate, maleate, 2-methylaspartate or erythro-3-hydroxy-aspartate which bind strongly to the native enzyme and thus acts as potent inhibitors in the reactions with monocarboxylic substrates did not exhibit any appreciable inhibitory effect on these reactions catalyzed by the arginine-modified enzyme. Proton NMR spectroscopy demonstrated that succinate strongly interacts with the native enzyme to generate substantial changes in the enzyme spectra whereas there was no such evidence for the specific interaction with this dicarboxylate with the arginine-modified enzyme.抄録全体を表示PDF形式でダウンロード (716K) -
Kikuko TAKEUCHI1982 年 91 巻 3 号 p. 1001-1007
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーMyosin and F-actin were prepared from bovine carotid arterial smooth muscle and the properties of the binding of myosin to F-actin were compared with those of the binding of skeletal muscle myosin to F-actin. The following differences were observed between skeletal and smooth muscle myosins.
1. The rate of ATP-induced dissociation of arterial actomyosin was equal to that of hybrid actomyosin reconstituted from arterial myosin and skeletal muscle F-actin, but was much lower than those of skeletal muscle actomyosin and of hybrid actomyosin reconstituted from skeletal muscle myosin and arterial F-actin.
2. The amount of ATP necessary for complete dissociation of arterial actomyosin was 2 mol/mol of myosin, although it is well known that skeletal muscle actomyosin is dissociated completely by the addition of 1 mol ATP per mol of myosin.
3. Arterial actomyosin and hybrid actomyosin reconstituted from arterial myosin and skeletal muscle F-actin did not dissociate upon addition of 0.1mM PPi, while skeletal muscle actomyosin dissociated completely.
4. In the absence of Mg2+, neither dissociation by ATP nor ATPase [EC 3. 6. 1. 3] activity was observed with arterial actomyosin and hybrid actomyosin reconstituted from arterial myosin and skeletal muscle F-actin. On the other hand, skeletal muscle actomyosin dissociated almost completely upon addition of ATP and showed a considerably high ATPase activity.
These observations reveal marked differences between myosins from skeletal and smooth muscles in their binding properties to F-actin.抄録全体を表示PDF形式でダウンロード (467K) -
Takashi MANABE, Setsuko JITZUKAWA, Noriaki ISHIOKA, Toshiaki ISOBE, Ts ...1982 年 91 巻 3 号 p. 1009-1015
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーExtremely acidic proteins in bovine brain extracts, including S-100 proteins and calmodulin, were separated by two-dimensional electrophoresis in the absence of denaturing agents. The pattern was compared with the patterns of other bovine tissue extracts and also with those of brain extracts of other species. S-100 proteins (S-100 a and S-100 b) were specifically abundant in nerve tissues. A small amount of S-100 proteins was detected in heart extract. Extracts of liver and kidney did not have S-100 proteins, but each showed the distribution pattern of acidic proteins characteristic to the tissue. Calmodulin seemed to be present in all tissue extracts examined. Comparisons of the patterns of acidic proteins in brain extracts of various animal species suggest that S-100 proteins are more “variable” in structure than calmodulin.抄録全体を表示PDF形式でダウンロード (2236K) -
Hidenori HAYASHI, Mitsue MIYAO, Sigehiro MORITA1982 年 91 巻 3 号 p. 1017-1027
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーBacteriochlorophyll (Bchl)-protein complexes were isolated from Rhodopseudoinonas palustris. Detergent treatment and polyacrylamide gel electrophoresis under rather mild conditions resulted in clear separation of light-harvesting Bchls into B 870 Bchls and B 800-850 Bchls as two distinctly different protein complexes. It was shown that almost all the Bchl contained in intracytoplasmic membranes was recovered as either B 870-reaction center complexes or B 800-850 complexes without loss of Bchls as free pigments. Furthermore, it was shown that the spectral form of each type of Bchl was not altered by this procedure for isolation, as judged by the calculated absorption spectrum which was the sum of the absorption spectra of the isolated complexes. Fluorescence measurement of the isolated complexes and intracytoplasmic membranes not only supported these ideas, but also indicated that the excited state was actually transferred from B 800-850 Bchls to B 870 Bchls. The isolation and measurements of absorption and fluorescence were carried out on spectrally different types of intracytoplasmic membrane from cells cultured under different culture conditions. The B 870-reaction center complexes from different types of intracytoplasmic membrane were spectrally identical. The B 800-850 complexes were widely different in absorption spectra, especially in the ratios of peaks at 800 and 850 nm, but exhibited similar fluorescence spectra.抄録全体を表示PDF形式でダウンロード (1292K) -
Hidenori HAYASHI, Tsunenori NOZAWA, Masahiro HATANO, Sigehiro MORITA1982 年 91 巻 3 号 p. 1029-1038
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーBacteriochlorophyll (Bchl)-protein complexes containing light-harvesting Bchls were isolated from Rhodopseudomonas palustris, and the CD spectra of these complexes were measured in the near-infrared region. These isolated Bchl-protein complexes retained the CD signals of light-harvesting Bchls that were observed in intracytoplasmic membrane preparation. Comparison of the CD spectrum of B 870-reaction center complexes with that of the isolated reaction centers revealed that the peak at 860 nm and the trough at 890 nm were attributable to the B 870 spectral form, and that the peak at 790 nm and the trough at 810 nm were not all attributable to the reaction center. The CD spectra of spectrally different types of B 800-850 complex revealed that the magnitudes of the peak at 840-850 nm and the trough at 860-870 nm were correlated with the magnitude of the absorption peak at around 850 nm. Therefore, these positive and negative CD bands were attributable to the B 850 spectral form. In a similar manner, the peak at 810-820 nm and trough at 790 nm were attributed to the B 800 spectral form.抄録全体を表示PDF形式でダウンロード (607K) -
Yasuhiro HASHIMOTO, Hideaki OTSUKA, Tamio YAMAKAWA1982 年 91 巻 3 号 p. 1039-1046
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーGlycolipids of erythrocytes from inbred mice, C3H/He and CDF1, were analyzed. Galactosylceramide, glucosylceramide, GM4 and GM2 were separated and their structures were established. Sialic acid of GM4 was exclusively N-acetylneuraminic acid, while GM2 contained only N-glycolylneuraminic acid. The fatty acid composition of GM4 was very similar to that of galactosylceramide, and a similarity was also found between that of GM2 and glucosylceramide. These results suggest that erythroid cells of mice have two separate biosynthetic pathways of gangliosides. One is the pathway to GM4 (NeuAc) from galactosylceramide, and the other is that for synthesizing GM2 (NeuGc) from glucosylceramide.抄録全体を表示PDF形式でダウンロード (972K) -
Shun NAKAMURA, Naoki NAKAYAMA, Kenji TAKAHASHI, Yoshito KAZIRO1982 年 91 巻 3 号 p. 1047-1063
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe complete amino acid sequence of Fragment B obtained by the limited tryptic digestion of E. coli polypeptide chain elongation factor To (EF-Tu) was determined. Seven peptides formed from Fragment B by cleavage with cyanogen bromide (designated as CB 1 to CB 7 according to their order of alignment from N- to C-termini of Fragment B) were purified, and six of them were completely sequenced by the manual method of sequential Edman degradation with direct identification of the phenylthiohydantoin-amino acids. The remaining one cyanogen bromide peptide (CB 6) containing 109 amino acid residues was further digested with trypsin. Twelve tryptic peptides (designated as T 1 to T 12 according to their order of alignment from N- to C-termini of CB 6) were isolated, and their amino acid sequences were analyzed.
The alignment of CB peptides was based on the results of the automated sequence analysis of Fragment B from its N-terminal, and the sequence analysis of the overlapping peptides containing sulfhydryl groups obtained by the complete tryptic digestion of Fragment B. The alignment of peptides T 1 to T 12 on CB 6 was based on the result of the automated sequence analysis of CB 6, and the sequence of the overlapping peptide obtained by the chemical cleavage of CB 6 at the tryptophan residue using cyanogen bromide in heptafluorobutyric acid. The nucleotide sequence of the tufA gene was also utilized for the alignment of these peptides.
Fragment B comprises amino acid residues 59 to 263 of E. coli EF-Tu, which consists of 393 amino acids. It contains two functional (SH1 and SH2) and one non-functional (SH3) sulfhydryl groups of EF-Tu. All of the five histidine residues in Fragment B were distributed within the first N-terminal quarter, and three of them were found to be clustered around SH2. Although E. coli EF-Tu consists of two gene products (tufA and tufB), no microheterogeneity was found in the amino acid sequence of Fragment B.抄録全体を表示PDF形式でダウンロード (1095K) -
Kiyoshi SUGAWARA, Yoshihiro OIKAWA, Takeshi OUCHI1982 年 91 巻 3 号 p. 1065-1071
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーPeptidylarginine deiminase, which catalyzes the deimination of arginyl residues in protein, was identified and partially purified from rabbit skeletal muscle. The specific activity of the crude extract from the muscle was about 120 times that of the extract from newborn rat epidermis. The enzyme was purified about 250-fold over the initial extract of rabbit skeletal muscle in a yield of about 53%. The enzyme requires Ca2+ as an essential cofactor and the activity was not inhibited by monoiodoacetate or PCMB. The molecular weight of the enzyme was found to be about 115, 000 by gel chromatography on Bio-Gel P-300. The enzyme catalyzed the deimination of arginyl residue when both the α-amino and α-carboxyl groups were substituted, and showed low activity when substrates had either a free α-amino or a free α-carboxyl group. The action of the enzyme on free L-arginine was negligible. Proteins such as protamine, histone, and ribonuclease A were better substrates than the other small synthetic peptides tested.抄録全体を表示PDF形式でダウンロード (410K) -
Antimo D'ANIELLO, John HAKIMI, Giuseppe M. CACACE, Costante CECCARINI1982 年 91 巻 3 号 p. 1073-1080
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーWe have isolated and purified, by affinity chromatography with Agarose-ε-aminocaproyl-fucosamine, an α-L-fucosidase [α-L-fucoside fucohydrolase EC 3. 2. 1. 51] from the hepatopancreas of Octopus vulgaris. In the purified fraction only fucosidase activity could be detected. However, two protein bands, one major (about 95 per cent) and one minor (about 5 per cent), were evident on sodium dodecyl sulfatepolyacrylamide gel electrophoresis. Isoelectric focusing also revealed two activities, pI 8.1 (major) and pl 7.3 (minor). Under denaturing conditions the molecular weight of the major band was estimated to be 52, 000 while that of the minor one was 43, 000. Only one major activity peak with an apparent molecular weight of 70, 000-75, 000 was detected by gel filtration chromatography. The enzyme has two optimal pH values, and the relative activities are temperature-dependent; one optimum is at pH 5.5±0.2 and the other at pH 3.0±0.2. We found that the enzyme has a maximum activity at about 70°C, but 50 per cent of the enzyme was inactivated at 70°C after 5min. The purified enzyme, using p-nitrophenyl-L-fucoside as substrate, has a specific activity of 38.9 units/mg of protein, Km of 3.58×10-4 at and Vmax of 65 μmolJmin/mg of protein. α-L-Fucose acts as a competitive inhibitor, with a Ki of 1.2×10-M. α-L-Fucosidase released radioactive fucose from cellular glycopeptides, but no detectable free fucose was released from 5 natural substrates.抄録全体を表示PDF形式でダウンロード (982K) -
Tetsuaki ABE, Gensaku OKADA, Hirobumi TERAOKA, Kinji TSUKADA1982 年 91 巻 3 号 p. 1081-1084
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe β-form of S-adenosylmethionine synthetase among three isozymes has been purified from rat liver, and proven to be homogeneous. The molecular weight of this enzyme was estimated to be 100, 000 by gel filtration on Sephacryl S-200, and the enzyme was shown to be composed of two subunits of 48, 000 daltons. A rabbit antiserum against the normal rat liver β-form of S-adenosylmethionine synthetase was used for immunochemical characterization. The α- and β-forms of isozyme are immunochemically identical, but the antiserum did not react with the γ-form from rat kidney.抄録全体を表示PDF形式でダウンロード (1505K) -
Katsuhiko NISHIMORI, Yoshiyuki KAWAGUCHI, Makoto HIDAKA, Takeshi UOZUM ...1982 年 91 巻 3 号 p. 1085-1088
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーThe nucleotide sequence of prorennin (prochymosin) cDNA cloned in E. coli was determined by the technique of Maxam and Gilbert. The longest prorennin cDNA insert in pTACR1 contained the putative signal sequence and the coding sequence for the peptide from the 1st amino acid, Ala (NH2 terminal), to the296th, Ser, and the other clone pTACR9 contained the coding sequence from the 258th, Asp, to the 365th, Ile (COOH terminal), and the TGA termination codon followed by the 3'-untranslated region. Thus, the whole coding sequence for prorennin was obtained in the pair of pTACR1 and pTACR9.抄録全体を表示PDF形式でダウンロード (279K) -
Kenji IKEHARA, Mayuko OKAMOTO, Kin-ichi SUGAE1982 年 91 巻 3 号 p. 1089-1092
発行日: 1982/03/01
公開日: 2008/11/18
ジャーナル フリーSporulation of Bacillus subtilis, growing exponentially in the presence of rapidly metabolizable nutrients, was induced by addition of decoyinine (an antibiotic inhibitor of GMP synthesis), and intracellular amounts of ppGpp were determined after 2M formic acid extraction by polyethyleneimine (PEI)-cellulose thin-layer chromatography. Consequently, it was found that the ppGpp in vegetative cells abruptly disappeared after the addition of decoyinine. This indicates that the disappearance of ppGpp is closely correlated to the initiation of B. subtilis sporulation.抄録全体を表示PDF形式でダウンロード (1409K)
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