巻号一覧
89 巻, 1 号
選択された号の論文の38件中1～38を表示しています
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Kazuhiro SUZUKI, Tadao TERAO, Toshiaki OSAWA1981 年 89 巻 1 号 p. 1-11
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーProtein kinase [EC 2. 7. 1. 37] of human erythrocyte membranes was solubilized with 0.5M NaCl in 5mM phosphate buffer, pH 6.7 at 4°C and purified on a CM-Sephadex C-50 column, followed by affinity chromatography on a histone-Sepharose 4 B column. The purified protein kinase gave a single band (molecular weight; 41, 000) on examination by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The optimum pH of the enzyme was 8.0 and a millimolar range of concentration of Mg2+ was required for its maximum activity. Histone and protamine were well phosphorylated by the protein kinase but casein and phosvitin were poor phosphate acceptors for the enzyme. The enzymic activity was not stimulated by cyclic AMP (cAMP). A cAMP-binding protein from human erythrocyte membranes inhibited the activity of the protein kinase, but the activity was restored with cAMP. A heat stable protein inhibitor from rabbit skeletal muscle also inhibited this enzyme. From these observations, this protein kinase seemed to be a catalytic subunit of the membrane bound cAMP-dependent protein kinase. This enzyme was strongly inhibited with Ca2+ in the presence of 1mM MgCl2. Various sulfhydryl reagents and polyamines also had inhibitory activity on the protein kinase. Natural substrates of the enzyme were investigated using heat treated membranes and 0.5M NaCl extracted membrane residues. Band 4.1, 4.2, and 4.5 proteins were phosphorylated but band 2 (spectrin) and band 3 proteins were poor substrates for this protein kinase.抄録全体を表示PDF形式でダウンロード (1949K) -
Keizo TESHIMA, Kiyoshi IKEDA, Kozo HAMAGUCHI, Kyozo HAYASHI1981 年 89 巻 1 号 p. 13-20
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe pH dependence of the binding constant of Ca2+ to phospholipases A2 [EC 3. 1. 1. 4] of N. naja siamensis, N. naja kaouthia, and N. raja atra was studied at an ionic strength of 0.1 and 25°C by measuring the decrease in tryptophyl fluorescence. All three enzymes exhibited precisely the same pH dependence. The binding constants at various pH values of the enzyme of N. naja naja, reported by Roberts et al. ((1977) J. Biol. Chem. 252, 6011-6017), fell practically on our pH dependence curve.
The pK value of an ionizable group was perturbed from 7.55 to 7.25 and protonation of another group with a pK value of 5.4 competed with the binding of the Ca2+ ion. The former group was assigned as a His residue corresponding to His 48 and the latter as Asp 49 in the active site on the basis of X-ray crystallographic results on the bovine pancreas enzyme (Dijkstra et al. (1978) J. Mol. Biol. 124, 53-60; Verheij et at. (1980) Biochemistry 19, 743-750). The pH dependence curve for porcine pancreas phospholipase A2, which was reported by Pieterson et al. ((1974) Biochemistry 13, 1439-1445) but is not yet well understood, was analyzed in a similar way on the basis of the pK value of His 48 estimated from the pH dependence of the tryptophyl fluorescence (van Dam-Mieras et al. (1976) Nobel Symp. 34, 177-197). The data were found to be well interpreted in terms of pK shifts of the α-amino group from 8.4 to 7.9 and of His 48 from 6.6 to 5.6 and in terms of protonation of Asp 49 with a pK value of 5.35, which competes with the Ca2+ ion binding. The pK shift of His 48 is in good agreement with those reported recently for equine and bovine enzymes (Verheij et al. (1980) Biochemistry 19, 743-750; Aguiar et al. (1979) Eur. J. Biochem. 100, 511-518).
The pH dependences of fluorescence intensity at 350nm (excited at 290nm) of a cobra phospholipase A2 of N. naja siamensis and its complex with Ca2+ were studied at an ionic strength of 0.1 and 25°C. Two other cobra enzymes also showed similar pH dependences. The curves were well interpreted in terms of participations of groups with pK values less than 2, 3.9, 9.75, and 11.1, in addition to the contributions from Asp 49 and His 48 perturbed by the Ca2+ ion binding.抄録全体を表示PDF形式でダウンロード (511K) -
Hiroshi NAKAMURA, Anthony N. MARTONOSI1981 年 89 巻 1 号 p. 21-28
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe mobility of spin labels covalently bound to the Ca2+-transport ATPase (ATP phosphohydrolase [EC 3. 6. 1. 3]) was studied by electron spin-resonance spectroscopy in purified ATPase and reconstituted vesicles. The purified ATPase of sarcoplasmic reticulum of rabbit skeletal muscle was covalently labeled with maleimide spin-labels of different chain length and the phospholipids were exchanged for dipalmitoylphosphatidylcholine.
The spectrum of the short-chain maleimide spin-label, bound to purified ATPase indicates reduced mobility after substitution of endogenous phospholipids with dipalmitoylphosphatidylcholine. With the long-chain maleimide derivative no difference was detected in the spectra, measured at 20-35°C temperature before and after substitution with dipalmitoylphosphatidylcholine. Below 10°C temperature the substitution with dipalmitoylphosphatidylcholine decreased the mobility of the prove, indicating that the microviscosity of environment in the vicinity of nitroxide groups was influenced by changes in the fatty acid composition.
With both short and long chain spin-labels bound to purified ATPase and sarcoplasmic reticulum vesicles the amplitude of weakly immobilized component sharply decreased in media containing 20-50% glycerol. Therefore, the mobility of covalently bound nitroxide group in short or long chain maleimide derivatives is also sensitive to the viscosity of the water phase.抄録全体を表示PDF形式でダウンロード (567K) -
Kiyoshi KONDO, Hiroko TODA, Kozo NARITA1981 年 89 巻 1 号 p. 29-36
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーPhospholipase A was purified 16.3-fold in terms of specific activity from the venom of Bungarus multicinctus by ion exchange chromatography on a CM-Sephadex C-25 column followed by gel filtration on a Sephadex G-75 column. The overall enzyme yield was 3.5% from the crude venom. The molecular weight and isoelectric point of the purified enzyme were estimated to be 14, 000 and 7.9 by electrophoresis on SDS-polyacrylamide gel and on polyacrylamide gel for isoelectric focusing, respectively. The enzyme was a single polypeptide chain consisting of 118 amino acids. Its N- and C-terminal residues were asparagine and glutamine, respectively. The enzyme was stable in the pH range of 2-10 and retained full activity after incubation for 24 h at 37°C. The optimum hydrolysis of egg yolk phosphatidyl choline was observed at pH 8.5 and the specific activity was 1, 450 units per mg of the enzyme. The enzyme was inactivated by treatment with p-bromophenacyl bromide, accompanied by the loss of one of two histidine residues. Research Institute for Microbial Diseases, Osaka University抄録全体を表示PDF形式でダウンロード (1033K) -
Kiyoshi KONDO, Hiroko TODA, Kozo NARITA1981 年 89 巻 1 号 p. 37-47
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーBungarus multicinctus phospholipase A was reduced and carboxymethylated. The RCM-enzyme was digested with TPCK-trypsin or cleaved with cyanogen bromide followed by chymotrypsin digestion. The resulting peptide mixtures were fractionated by gel filtration on Sephadex G-50 and G-25 columns or by DEAE-cellulose (DE-32) column chromatography. Further purification of the peptide mixtures was performed by paper electrophoresis at pH 3.5 or 6.5 or by paper chromatography. The sequences of isolated peptides were determined by the manual Edman or dansyl-Edman method. From the sequences of these peptides the whole enzyme sequence (total 118 residues) was deduced. The complete sequence of the enzyme is similar to those of phospholipases A2 from other snake venoms and mammalian pancreas. Further, a 58% sequence homology was found between the present phospholipase A and the A chain of β1-bungarotoxin, a presynaptic neurotoxin having weak phospholipase A activity, contained in the same venom.抄録全体を表示PDF形式でダウンロード (686K) -
Kaoru MIYAMOTO, Yoji ARATA, Hiszyuki MATSUO, Kozo NARITA1981 年 89 巻 1 号 p. 49-59
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーRibonuclease St consists of 101 amino acid residues in a single polypeptide chain with one disulfide bond. It has two histidines Iccated at positions 60 and 91 from the amino terminus. The pKa values of His-60 and His-91 were estimated by hydrogen-tritium exchange titration to be 8.0 and 6.3, respectively, and these values were confirmed by 1H NMR titration. The high pKa value of His-60 suggests that it interacts with a neighboring negative charge, presumably of a carboxylate. This is suggested by the presence of an inflection at pH 4.5 in the 1H NMR titration plot for His-60. The 1H NMR titration plot for His-91 also suggests its interaction with a carboxylate, although the pKa of His-91 was close to that of unperturbed histidine residues. This suggests that a positively charged group is also located in the vicinity of His-91.
It was concluded that His-91 is one of the active site residues of the enzyme. The pKa for His-91 was shifted to the alkaline side in the presence of 3'-GMP, a competitive inhibitor, in the titration plots observed by both hydrogen-tritium exchange and 1H NMR spectroscopy. The 31P NMR titration data suggest that in the 3'-GMP-RNase St complex the dianion form of the nucleotide participates in the interaction with the protonated form of His-91. The existence of another positively charged group with pKa of 7.0 was also suggested on the basis of the 31P NMR data.抄録全体を表示PDF形式でダウンロード (704K) -
Toshihiro TSUDZUKI1981 年 89 巻 1 号 p. 61-69
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリー1. A synaptic vesicle fraction isolated from bovine caudatolenticular nuclei showed enzymic activities of tyrosine hydroxylase [EC 1. 14. 16. 2] and dopamine β-hydroxylase [EC 1. 14. 17. 1]. Tyrosine hydroxylase, whose subcellular localization is uncertain, appeared to be associated with the synaptic vesicles.
2. The vesicle fraction took up [3H] dopamine increasingly with time without the aid of ATP (6.3 pmol of [3H]dopamine per mg of vesicle proteins, or 3-4% of the added dopamine, at 30min). In the presence of ATP, a transient accumulation of the amine was observed, reaching the highest level at 7-10min (5.6 pmol dopamine/mg protein), and then a rapid release of the amine took place, obeying firstorder kinetics with respect to the amine concentration. The amine uptake was strongly inhibited with NEM, regardless of the presence or absence of ATP.
3. The vesicle fraction also exhibited a weak ability to translocate protons inward and ATP-dependently, as monitored by an increase in the fluorescence intensity of ANS. The fluorescence enhancement persisted for at least 30min and this timedependent change was not consistent with that of the transient accumulation of [3H]dopamine mentioned above. Since the present vesicle preparation contained a small amount of mitochondrial ATPase (18-20% of the total activity), the proton translocating ability could be attributable to contaminating submitochondrial particles.
4. Therefore these results made it impossible to conclude that the transient uptake of [3H]dopamine by the synaptic vesicles was coupled to ATP hydrolysis.抄録全体を表示PDF形式でダウンロード (707K) -
I. Diffraction Pattern of the Photoreaction Unit Isolated from Rhodospirillum rubrum Chromatophore and Some Characteristics of the StructureMikio KATAOKA, Tatzuo UEKI1981 年 89 巻 1 号 p. 71-78
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe X-ray diffraction pattern from chromatophore membranes of a photosynthetic bacterium, Rhodospirillum rubrum, indicates that a highly organized protein assembly exists in the membrane. The X-ray scatterer was solubilized from chromatophores by a mixture of cholate and deoxycholate. The basic component was identified as the photoreaction unit, which consists of light-harvesting bacteriochlorophyll proteins and a reaction center.
The radial autocorrelation function, calculated directly from the X-ray intensity data, made it possible to deduce certain structural features of the X-ray scatterer.
1. The maximum dimension of the X-ray scatterer is estimated to be 110-130 Å.
2. The arrangement of the units in the chromatophore membrane is random.
3. Protein molecules in the unit form a rigid structure, being arranged mutually in fixed positions to give a distinct X-ray diffraction pattern.
4. The most probable structure is one which has rotational symmetry.抄録全体を表示PDF形式でダウンロード (2035K) -
Akio MURAKAMI, Mamoru MIMURO, Kaori OHKI, Yoshihiko FUJITA1981 年 89 巻 1 号 p. 79-86
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe absorption spectrum of allophycocyanin of Anabaena cylindrica was studied.
The extinctions of the main absorption bands (650 and 620nm) varied depending on the protein concentration, ionic strength, and pH. At higher protein concentrations or higher ionic strength, the 650nm band became stronger and the 620nm band became weaker. At pH values lower than 6.0, reverse changes occurred in association with protein dissociation into monomer. Similar spectral variation was also induced by sugars and polyols. Glucose, sucrose, or glycerol (1-5M) induced an increase in the 650 run band and a decrease in the 620 run band without causing any changes in protein conformation. Propylene glycol and ethylene glycol showed a reverse effect and caused protein dissociation into monomer. The difference spectra of all spectral changes were identical, consisting of a sharp and strong peak at 650nm and a broad and weak one in the reverse direction at a wavelength below 620nm. The spectral variation probably results from shifts of the electronic state of phycocyanobilin.
We postulated that a protein field favorable to the state producing the 650 nm band is established around phycocyanobilin when the protein takes a “tight state” through protein association or by the action of sugar in aqueous environment; in a “relaxed state” in the monomer, the state of phycocyanobilin similar to that in phycocyanin becomes dominant.抄録全体を表示PDF形式でダウンロード (572K) -
Michiyuki KASAI, Hirofumi ONISHI, Shizuo WATANABE1981 年 89 巻 1 号 p. 87-101
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe ATPase or ITPase reaction and ATP- or ITP-induced superprecipitation were studied as a function of the ATP or ITP concentration with suspensions of chicken gizzard “native” myosin B or “reconstituted” myosin B (a combination of actin, myosin, and native tropomyosin). The specific aim of the study was to answer the following questions:
i) Is the superprecipitation or the ATPase reaction sensitive to calcium ions even at very low concentrations of ATP?
ii) Is tropomyosin required for calcium sensitivity?
iii) Does “native” myosin B from gizzard muscle behave differently from “reconstituted” myosin B?
iv) Does the troponin-tropomyosin complex of rabbit skeletal muscle act as a regulatory protein for the contractile activity of acto-phosphorylated myosin?
Considering the overall time course of reaction rather than single values of activity, we found that the answers to the first three questions were negative, while that to the last question was positive. These results favor the kinase-phosphatase mechanism of calcium regulation rather than the leiotonin mechanism.抄録全体を表示PDF形式でダウンロード (2048K) -
Masayasu BANDO, Akira NAKAJIMA, Kenshi SATOH1981 年 89 巻 1 号 p. 103-109
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーA low molecular weight yellow substance with absorption maxima at 228, 263, and 365nm was separated from the water soluble fraction in human lens by gel filtration on a Sephadex G-15 column. The absorption spectrum of the yellow substance shifted to that of 3-OH L-kynurenine (absorption maxima; 228, 267, and 368 nm) after hydrolysis with β-glucosidase [EC 3. 2. 1. 21]. Concomitantly, its absorbances at 228 and 365nm decreased; the spectra of both compounds intersect at 235, 249, 263, 305, and 387nm (isosbestic points). The hydrolytic product of the yellow substance was shown to contain 3-OH L-kynurenine (by amino acid analysis) and glucose (by gas chromatography). The yellow substance was thus identified as 3-OH L-kynurenine O-β-glucoside. Since the molar extinction coefficient of authentic 3-OH L-kynurenine was found to be 3650M-1•cm-1 at 368nm, the molar extinction coefficient of the glucoside can be calculated to be 4340M-1•cm-1 at 365nm from the absorbance ratio of the glucoside at 365nm and of 3-OH L-kynurenine at 368 nm to the absorbances at the isosbestic points.
By employing the molar extinction coefficient thus obtained, the amount of 3-OH L-kynurenine O-β-glucoside isolated from human lens was estimated. The glucoside content in whole lens and the specific content, expressed as pmol per g lens protein, both decrease with age. In particular, the specific content decreases linearly with age over the period from birth to the age of 30-40, and subsequently it seems to remain at a constant level.抄録全体を表示PDF形式でダウンロード (435K) -
Toshiaki HIRATSUKA, Koki UCHIDA1981 年 89 巻 1 号 p. 111-123
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe location of the lysyl residues which were accessible to labeling with a fluorescent reagent, N-methyl-2-anilino-6-naphthalenesulfonyl chloride (Mns-C1), in the presence or absence of divalent metal ions was characterized by following the fluorescent peptides released from the labeled myosin on chymotryptic digestion.
The Mns groups were mainly (more than 90%) incorporated into myosin heavy chains (HCs), not into light chains (LCs) (less than 6%). The groups were also found to remain in chymotryptic heavy meromyosin (more than 80%). When the labeled myosin molecule was cleaved into subfragment-1 (S-1) and myosin rod, most (more than 86%) of the groups were found in the released peptides, Mns-P1 (6, 600 daltons) and a further degraded peptide, Mns-P2 (4, 400 daltons), but not in S-1 or the rod (less than 9%). The fluorescent peptides corresponding to Mns-P1 and Mns-P2 were also produced by chymotryptic digestion of HC fraction separated from the labeled myosin but not by similar digestion of LCs. The rate of production of these peptides from myosin was nearly equal to that of S-1-HC. The isolation of the peptides was achieved by gel filtration on Sepharose 6B in 6M guanidine-HCl. There was no significant difference in results between myosins labeled in the presence and absence of divalent metal ions.
The N-terminal end analysis of Mns-P1 by the 1-dimethylaminonaphthalene-5-sulfonyl (Dns) method yielded a single N-terminal amino acid, alanine. On the other hand, S-1-HC showed no α-N-Dns-amino acid suggesting that the S-1 head retains its blocked N-terminal end even after the production of Mns-P1. Taking this result into consideration, we concluded that the peptides containing the lysyl residues accessible to labeling by Mns-C1 were released from the S-1/subfragment-2 link region of cardiac myosin HC.抄録全体を表示PDF形式でダウンロード (3466K) -
Tomoko TAKAHASHI, Norio INOKUCHI, Masachika IRIE1981 年 89 巻 1 号 p. 125-134
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリー1. A major glucoamylase [EC 3. 2. 1. 3] of Aspergillus saitoi was purified by ultrafiltration followed by successive chromatography on DEAE-Sephadex, Ultrogel AcA 44 and SP-Sephadex. The purification achieved was 23-fold from crude extract with a yield of 21%. The purified enzyme, named Glue M1, was proved homogeneous as judged by polyacrylamide gel electrophoresis, isoelectric focusing, ultracentrifugation, and also from the absence of the glycosidase activities detected in crude extract.
2. Gluc M1 was a glycoprotein containing 18% neutral sugar and 0.77% glucosamine, and its molecular weight was estimated to be about 90, 000 by SDS-polyacrylamide gel electrophoresis and amino acid composition. The N-terminal amino acid was identified as alanine.
3. The pH optimum of Gluc M1 was 4.5 with soluble starch as a substrate. The enzyme was stable between pH 2.5 and 7.5 and retained full activity at temperatures up to 50°C. The enzyme activity was inhibited by Hg2+ and, to a lesser extent, by Pb2+ and Mn2+.
4. The Km value for malto-oligomer markedly decreased with increasing chain length of substrate in glucose unit (n) and the Vmax value increased with n, thus resulting in the increase in the Vmax/Km value with n. The kinetic parameters for other substrates such as soluble starch, glycogen and isomaltose as well as the K1 values for some saccharides were also determined.抄録全体を表示PDF形式でダウンロード (1293K) -
Hiroshi NAKADA, Takaya SAWAMURA, Yutaka TASHIRO1981 年 89 巻 1 号 p. 135-141
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーBiosynthesis of a hepatic binding protein specific for asialoglycoproteins and its subsequent insertion into microsomal membrane were studied by using antibody monospecific for the binding protein. 125I-Labeled antibody binds much more preferentially with membrane-bound ribosomes than with free ribosomes, and nascent binding protein labeled with [3H] puromycin was detected exclusively on tightly membrane-bound ribosomes, which can be detached from the membrane by puromycin treatment in the presence of high salt buffer. When rough microsomes labeled in vivo with 14C-amino acid mixture were digested with protease, nascent binding protein was effectively protected from the digestion like nascent albumin (_??_90%). When rough microsomes labeled in vitro with [3H]puromycin were digested with protease, the degree of protection of albumin was again_??_90%, whereas that of the binding protein was only_??_50%. The carbohydrate moieties of the binding protein and the bulk of glycoproteins in the microsomes labeled in vivo with [3H]glucosamine and [3H]mannose were also effectively protected from the protease digestion (_??_90%). These results indicate that the binding protein is exclusively synthesized on the membrane-bound ribosomes and spans the microsomal membrane probably exposing the carboxyl-terminal segment on the cytoplasmic surface and the amino-terminal segment charged with carbohydrate moieties on the lurninal surface, respectively.抄録全体を表示PDF形式でダウンロード (559K) -
Michitoshi NAKAMURA, Yoshiyuki SAKAKI, Nobuko WATANABE, Yasuyuki TAKAG ...1981 年 89 巻 1 号 p. 143-152
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーCa2+ plus Mg2+-dependent endodeoxyribonuclease was extracted from calf thymus chromatin and purified to a state free from contamination by other DNases. This DNase required both Ca2+ and Mg2+, or Mn2+ alone for its activity and the optimum pH for activity was at 6.5-7.5. No specificity for the 5'-base was observed. The molecular weight of the DNase was estimated to be about 25, 000-30, 000 by glycerol gradient centrifugation. Actin and antibody for pancreatic DNase (DNase I) did not inhibit the enzyme, whereas both strongly inhibited DNase I, suggesting that these two DNases are different enzymes.抄録全体を表示PDF形式でダウンロード (1199K) -
Kenji HIROTA, Tomoharu GOMI, Ryutaro KISHIMOTO, Masao IGUCHI, Ken-ichi ...1981 年 89 巻 1 号 p. 153-160
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーIn studies with a synthetic androgen, R 1881, an androgen-binding component was found in the cytosol of human placental villi. Kinetic analysis indicated that the Kd value of this component was 1.4nM at 0-4°C and that binding of R 1881 amounted to 277±73 fmol/mg protein. Glycerol density gradient ultracentrifugation showed a peak of binding activity in the 8S region in a medium of low ionic strength, but in the 4.5S region in a medium containing 0.5M KCl. The R 1881-binding component was inactivated by mild heat- or trypsin-treatment, but not by treatment with DNase or RNase. Most of the R 1881-binding activity was sedimented at 20 to 40% saturation of ammonium sulfate. These findings indicate that the R 1881-binding component in human placental cytosol is quite similar in its characteristics to androgen receptors, which are present in various androgen-responsive organs. Testosterone was a more potent competitor of R 1881-binding than DHT or cyproterone acetate. Scatchard plots indicated that the binding site of testosterone was identical with that of R 1881. These findings suggest that the androgen receptor in placental cytosol is specific for testosterone. The Kd value for testosterone was calculated to be 3.2nM.抄録全体を表示PDF形式でダウンロード (630K) -
Yoshitaka OHKUBO, Ikuo FUNAKOSHI, Ikuo YAMASHINA1981 年 89 巻 1 号 p. 161-167
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーHeparitinase [EC 4. 2. 2. 8, heparitin sulfate lyase] was prepared from an extract of cultured cells of Flavobacterium heparinum. Purification of the enzyme was achieved by repeating the hydroxyapatite column chromatography.& The enzyme was used to degrade heparan sulfate occurring on the surfaces of ascites hepatoma cells, AH 66. From the supernatant of the enzyme-treated cells, breakdown products from heparan sulfate could be detected by paper chromatography. The heparitinase was found to be more effective than trypsin in removing heparan sulfate from the cells. Furthermore, on analyzing glycosaminoglycans and glycopeptides from the enzyme-treated cells and control cells, it was concluded that heparan sulfate was exclusively present on the cell surface and accessible to the heparitinase whereas other cell surface complex carbohydrates remained intact.抄録全体を表示PDF形式でダウンロード (525K) -
Makoto SASAKI, Keiko TANIGUCHI, Kayoko MINAKATA1981 年 89 巻 1 号 p. 169-177
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe thiol proteinase inhibitor in human plasma (and serum) was separated into 3 forms [P-1 (S-1), P-2 (S-2), and P-3 (S-3)] by linear gradient elution on a DEAE cellulose column. The individual inhibitors were purified to a functionally pure state by gel filtration on a Sephadex G-150 column, starch block electrophoresis and affinity chromatography on a trypsin•hymotrypsin-Chromagel A-2 column. The largest molecular weight inhibitor P-3 was further purified by chromatography on an anti-albumin column and by preparative polyacrylamide gel electrophoresis; the final preparation appeared homogeneous by immunoelectrophoresis and analytical polyacrylamide gel electrophoresis. Monospecific antiserum against P-3 was prepared by immunizing rabbits with purified P-3. The three forms of inhibitor showed similar pH stability curves and inhibition spectra on the proteolytic (casein substrate) and amidase (Bz-Arg-pNA, and Bz-Tyr-pNA) activities of ficin, papain, trypsin, and chymotrypsin. Moreover, the antibody against P-3 suppressed the inhibitory activities of P-1, P-2, and P-3 to similar extents in various antibody concentrations, and no spur was formed between the precipitin lines of the three forms against anti-P-3 antibody by double immunodiffusion. However, the three forms differed in molecular weight and isoelectric point [mol. wt. and pI for P-1 (S-1), 90, 000 and 4.5 (85, 000 and 4.45); for P-2 (S-2), 95, 000 and 4.4 (94, 000 and 4.35); for P-3 (S-3), 167, 000 and 4.1 (150, 000 and 4.0)]. P-3 was the most heat-stable, showing no decrease in inhibitory activity when heated up to 70°C for Ih; P-1 and P-2 were stable up to 50°C. P-1 (S-1) and P-2 (S-2) migrated in the α2-region and P-3 (S-3) in the α1-region in accordance with the difference in their isoelectric points. Thus, the term α1-TPI is recommended for P-3 (S-3), and the terms α2-TPI1 and α2-TPI2 for P-2 (S-2) and P-1 (S-1), respectively. These data indicate that human plasma contains three different forms of thiol proteinase inhibitor, which have the same antigenicity.抄録全体を表示PDF形式でダウンロード (1619K) -
Keiko TANIGUCHI, Jinichi ITO, Makoto SASAKI1981 年 89 巻 1 号 p. 179-184
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe urinary thiol proteinase inhibitors u-TPI1 and u-TPI2 were partially purified from human urine by gel filtration on Sephadex G-50 and Sephadex G-100 columns, and affinity chromatography on a trypsin•chymotrypsin-Chromagel A-2 column. They showed similar inhibition spectra to that of plasma inhibitors, inhibiting ficin strongly and papain moderately, but not inhibiting trypsin and chymotrypsin. The molecular weights of u-TPI1 and u-TPI2 were determined to be 76, 000 and 22, 500 by gel filtration on Sephadex G-150 and G-75, respectively, and their isoelectric points were found to be 4.6 and 4.8 by isoelectrofocusing. u-TPI1 and u-TPI2 were labile at acidic pH, but stable at neutral and alkaline pH. Both inhibitors were relatively thermostable, showing no decrease in activity on heating up to 50°C for 1h. The antibody against plasma thiol proteinase inhibitor al-TPI suppressed the activities of the urinary inhibitors significantly, and on double immunodiffusion formed clear precipitin lines with both a-TPI1 and u-TPI2. On immunoelectrophoresis a-TPI1 migrated in the α2-region and a-TPI2 in the β1-region. It is concluded from these data that the urinary thiol proteinase inhibitors are degradation products of the plasma inhibitors.抄録全体を表示PDF形式でダウンロード (1004K) -
Hideki UCHIYAMA, Kinzo NAGASAWA1981 年 89 巻 1 号 p. 185-192
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーA hog-mucosal heparin purified gel-chromatographically (total sulfate, 2.20; N-sulfate, 0.82; N-acetyl, 0.15 (mol/mol HexN); activity, 184 USP units/mg) was partially N-desulfated to give a product (total sulfate, 2.12; N-sulfate, 0.71 (mol/mol HexN); activity, 159 USP units/mg). The free amino groups in the product was extensively labeled with fluoresceinylthiocarbamoyl (FTC) groups, and the labeled product was chromatographed on Octyl-Sepharose CL-4B to give a heparin preparation of fluorescein-labeled species (total sulfate, 2.04; N-sulfate, 0.72; degree of substitution, 0.059 (mol/mol HexN); activity, 155 USP units/mg). The fluorescent heparin thus obtained was indicated from its analytical data to have one FTC group per heparin molecule irrespective of the molecular weight.
The fluorescent heparin was separated into the low-affinity (56.6%) and highaffinity (43.4%) fractions for antithrombin III, and the anticoagulant activities of the two types of fluorescent heparin were compared with those of the starting heparin and the partially N-desulfated heparin, suggesting that FTC-substitution in heparin molecules had no effect on the known biological interaction with mobilized or immobilized antithrombin III.抄録全体を表示PDF形式でダウンロード (524K) -
Kazuto NINOMIYA, Shuji TANAKA, Shuji KAWATA, Satoru MAKISUMI1981 年 89 巻 1 号 p. 193-201
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーAn aminopeptidase was purified about 1, 700-fold from seeds of Japanese apricot (Prunus mume Sieb.) by a seven-step procedure comprising extraction from seeds, ammonium sulfate fractionation, DEAE-cellulose chromatography, first and second DEAE-Sepharose chromatography, hydroxyapatite chromatography, and Sephadex G-200 gel filtration. The purified enzyme was shown to be homogeneous on polyacrylamide gel electrophoresis. The molecular weight of the enzyme was estimated to be about 56, 000 by gel filtration on Sephadex G-200 and the isoelectric point was 4.9. The pH optimum for L-leucine β-naphthylamide was between pH 6.5 and 7.0, and the enzyme was stable in the pH 5.0 to 8.3 region and up to 50°C. The enzyme hydrolyzed a variety of aminopeptidase substrates with a free a-amino group. Of the amino acid, β-naphthylamides, the enzyme was highly specific for substrates with a hydrophobic side chain in the amino terminal residue. The enzyme was strongly inhibited by p-chloromercuribenzoate, heavy metals, diethyl pyrocarbonate, and photooxidation with methylene blue, but was not affected by thiol compounds, peptidase inhibitors of microbial origin, such as bestatin and puromycin, or metal chelating agents. No activation of the enzyme by metal ions was observed. These results suggest that the enzyme is a true aminopeptidase in which cysteine and histidine residues participate in the catalytic process, and is not classifiable as a metalloenzyme.抄録全体を表示PDF形式でダウンロード (1080K) -
Toichiro HOSOYA, Takashi SAITO1981 年 89 巻 1 号 p. 203-215
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリー1. The uterine peroxidase activity of rats was determined quantitatively at each stage of the estrous cycle, and it was found that the protein-based and DNA-based specific activities in proestrus and estrus are 4-5 times higher than those in diestrus. Ovariectomy caused a marked decrease in the activity in the uterus, and the administration of estrogen, but not other steroids, restored the activity. Of many organs in normal rats, the uterus had the greatest peroxidase activity. The peroxidase activity of pig uterus varied from animal to animal and the mean specific activity was about one-hundredth of that of rats.
2. The peroxidase activity of uterine tissue was mainly associated with subcellular particulates, especially microsomal fractions. The membrane-bound peroxidase showed a cyanide-difference spectrum which was very similar to those of lacto-peroxidase and thyroid peroxidase.
3. Rat uterine fluid peroxidase was also found to be estrogen-dependent and to exhibit a similar cyanide-difference spectrum.
4. On the basis of spectroscopic, kinetic, and other properties, the relationship between the uterine tissue peroxidase, uterine fluid peroxidase and eosinophil peroxidase is discussed.抄録全体を表示PDF形式でダウンロード (958K) -
Tsutomu MIURA, Yoshiko MATSUDA, Akihiko TSUJI, Nobuhiko KATUNUMA1981 年 89 巻 1 号 p. 217-222
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーAntisera to purified γ-glutamyltranspeptidase (γGTP) from human and rat kidney were prepared, and their reactivities toward purified γGTP from kidney, liver, and bile were tested. The following results were obtained:
1. On double immunodiffusion, Triton-solubilized γGTP, and papain-solubilized γGTP from rat kidney gave single precipitin lines which fused completely against antiserum to the purified enzyme from rat kidney.
2. An antigen-antibody complex of human kidney γGTP retained about 50% of the catalytic activity of the antigen.
3. Double immunodiffusion showed that the enzymes from human liver, kidney, and bile were immunologically identical.
4. Antiserum to rat kidney γGTP partially cross reacted with human γGTP, but antiserum to human γGTP reacted only very weakly with rat γGTP.
It is concluded that γGTP of human liver, kidney, and bile are immunologically identical and that rat γGTP and .human γGTP have certain antigenic determinants in common.抄録全体を表示PDF形式でダウンロード (1623K) -
Ryohei YAMAMOTO, Yumiko UMEDA, Akira KOSAKA, Kanefusa KATO1981 年 89 巻 1 号 p. 223-229
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーA sensitive enzyme immunoassay system for the measurement of antibodies in serum was developed by the use of a separation method based on the thiol-disulfide interchange reaction.
Serum samples including antibodies (anti-insulin, anti-human chorionic gonadotropin, or anti-β-D-galactosidase) were incubated with antigens labeled with β-D-galactosidase from Escherichia coli. Each reaction mixture was then passed through a small column (0.1ml) of (anti-IgG)IgG-Sepharose 4B, in which the (anti-IgG)IgG had been coupled by means of a disulfide bond. The column was washed to remove the unbound label, then the antibody-bound label was eluted from the column with a buffer containing 25mM dithiothreitol, which cleaved the disulfide bonds between the Sepharose matrix and the anti-IgG antibody molecules. By measuring the enzyme activity in the eluate, the amount of antibodies could be determined even in a serum sample which contained antibodies corresponding to as little as 0.01% of the standard antisera. Preliminary experiments showed that the present method can be used to detect the anti-insulin antibody in the sera from insulin-treated diabetic patients.抄録全体を表示PDF形式でダウンロード (500K) -
Yasuyuki SUZUKI, Masatoshi ITO, Hyogo SINOHARA1981 年 89 巻 1 号 p. 231-236
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーThe sex-steroid-binding plasma protein (SBP), which had been reported to be absent in the rat by several workers, was detected in 6-week-old male rats, but not in female rats aged 5-43 days. The rat SBP was purified to apparent homogeneity by affinity chromatography on testosterone-17α-ethynylcarboxyaminoethyl Sepharose 4B followed by hydroxyapatite column chromatography, and its properties were compared with those of rabbit SBP prepared in exactly the same fashion. The concentration of SBP in adult male rabbit was 25-fold greater than that in 6-week-old male rat, but the binding characteristics of both SBPs were very similar. They specifically bind testosterone, 5α-dihydrotestosterone, and 5α-androstane-3α, 17β-diol, but have virtually no affinity for estradiol, progesterone, or cortisol. Equilibrium dissociation constants for dihydrotestosterone were estimated to be 11.7 nm for rat SBP and 14.9 ntvt for rabbit SBP.抄録全体を表示PDF形式でダウンロード (406K) -
Nobuhiro HARADA, Tsuneo OMURA1981 年 89 巻 1 号 p. 237-248
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーTwo forms of cytochrome P-450, P-450 PB and P-450 MC, were purified to homogeneity from the liver microsomes of phenobarbital (PB)-treated and 3-methylchol-anthrene (MC)-treated rats, respectively. Rabbit antibodies against P-450PB and P-450 MC were prepared and the monospecificity of each antibody preparation was confirmed by various lines of evidence. By the use of these antibodies, the contents of P-450 PB and P-450 MC in microsomes could be determined separately by quantitative immunoprecipitation. P-450 PB and P-450 MC each amounted to about 10 of total cytochrome P-450 in the microsomes of normal rats. However, each of them was selectively and substantially increased by the appropriate inducer, and became a predominant component of cytochrome P-450 in the microsomes of drugtreated animals. The increase of each specific molecular species of cytochrome P-450 was about 10- to 20-fold within 48 h, whereas the increase of total cytochrome P-450 was only about 2- to 3-fold even after maximal induction by the drugs.
The drug oxidation activities of P-450PB and P-450MC were also significantly altered by the drug treatments. The administration of MC to PB-treated rats induced a drastic decrease in the P-450 PB-dependent oxidations of benzo (a) pyrene and 7-ethoxycoumarin, while the corresponding activities of P-450 MC increased sharply, and these changes were much more rapid than the change of the amount of each form of cytochrome P-450. However, the oxidation of benzphetamine was almost exclusively P-450 PB-dependent even after extensive induction by MC. These observations suggest that the specific activities of P-450 PB and P-450 MC in the oxidations of various drugs are quite differently affected by the induced states of animals.抄録全体を表示PDF形式でダウンロード (1663K) -
Yohtalou TASHIMA, Masahiro HASEGAWA, Lois K. LANE, Arnold SCHWARTZ1981 年 89 巻 1 号 p. 249-255
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーSpecific effects of spermine on Na+, K+-ATPase were observed using an enzyme partially purified from rabbit kidney microsomes by extraction with deoxycholate.
1. Spermine competed with K+ for K+-dependent, ouabain-sensitive nitrophenyl-phosphatase. The K1 for spermine was 0.075mM in the presence of 1mM Mg2+ and 5mM p-nitrophenylphosphate at pH 7.5.
2. Spermine activated Na+, K+-ATPase over limited concentration ranges of K+ and Na+ in the presence of 0.05mM ATP. The spermine concentration required for half maximal activation was 0.055mM in the presence of 1mM K+, 10mM Na+, 1mM Mg2+, and 0.05mM ATP.
3. The activation of Na+, K+-ATPase was not due to substitution of spermine for K+, Na+, or Mg2+.
4. When the concentration of K+ or Na+ was extremely low, or in excess, spermine did not activate Na+, K+-ATPase, but inhibited it slightly.
5. Plots of 1/v vs. 1/[ATP] at various concentrations of spermine showed that spermine decreased the Km for ATP without changing the Vmax.
6. Plots of 1/v vs. 1/[ATP] at concentrations of K+ from 0.05mM to 0.5mM showed that K+ increased the Km for ATP with increase in the Vmax in the presence of 0.2mM spermine similarly to that in the absence of spermine.
The contradictory effects of spermine on this enzyme system suggest that the
K+-dependent monophosphatase activity does not reflect the second half (the dephosphorylation step) of the Na+, K+-ATPase catalytic cycle.抄録全体を表示PDF形式でダウンロード (477K) -
Makoto FUJISAKI, Kiyoshi SUGAWARA1981 年 89 巻 1 号 p. 257-263
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーAn enzyme which catalyzes the coversion of arginyl residues to citrullyl residues in protein was obtained from the extract of the epidermis of newborn rats. The enzyme required Ca2+ for its activity. The enzyme activity was enhanced in the presence of DTT. The maximum activity was observed at pH 7.5 at 50°C in the presence of 10 mat CaCl2 and 2mM DTT. The activity was inhibited strongly by treatment of the enzyme with monoiodoacetate or PCMB, which suggests that the epidermal enzyme is an SH-enzyme. The molecular weight of the enzyme was calculated by gel filtration to be about 48, 000. It was essential for the α-amino or α-carboxyl group of the L-arginine substrate to be involved in a peptide linkage. The enzyme showed marked activities towards N-substituted L-arginine derivatives such as Bz-L-Arg, Bz-L-Arg-NH2, and Bz-Gly-L-Arg, but the action of the enzyme on free L-arginine was negligible. The enzyme activity was affected by the nature of the residue neighboring the arginyl residue in proteins. The authors propose the name “peptidylarginine deiminase” for this enzyme. A considerable specificity of the enzyme for proteins from the epidermal cells in terminal differentiation was observed. The results suggest that citrullyl residues in membranous protein of horny cells of the epidermis of newborn rat are formed by the action of epidermal peptidylarginine deiminase.抄録全体を表示PDF形式でダウンロード (526K) -
Tateo YAMANAKA, Yuhsuke KAMITA, Yoshihiro FUKUMORI1981 年 89 巻 1 号 p. 265-273
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーCytochrome c oxidase (cytochrome aa3-type) [EC 1. 9. 3. 1] was purified from Nitrobacter agilis to an electrophoretically homogeneous state and some of its properties were studied.
The enzyme showed absorption peaks at 422, 598, and 840 nm in the oxidized form, and at 442 and 606 nm in the reduced form. The CO compound of the reduced enzyme showed peaks at 436 and 604 nm, and the latter peak had a shoulder at 599 nm. The enzyme possessed 1 mol of heme a and 1.6g-atom of copper per 41, 000g, and was composed of two kinds of subunits of 51, 000 and 31, 000 daltons. These results show that the structurally minimal unit of the enzyme molecule is composed of one molecule each of the two subunits and contains 2 molecules of heme a and 2-3 atoms of copper.
The enzyme rapidly oxidized ferrocytochromes c of several eukaryotes as well as N. agilis ferrocytochrome c-552. The reactions catalyzed by the enzyme were strongly inhibited by KCN. The reduction product of oxygen catalyzed by the enzyme was concluded to be water on the basis of the ratio of ferrocytochrome c oxidized to molecular oxygen consumed.抄録全体を表示PDF形式でダウンロード (1642K) -
Hitoshi SAWADA, Masao AZEGAMI, Shin-ichi ISHII1981 年 89 巻 1 号 p. 275-284
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーA bacteriolytic_??_nzyme was found to be produced, concomitantly with the progeny phage, in Pseudomonas aeruginosa P14 infected with phage PS17. The enzyme, named PS17-lysozyme, was purified by acrinol treatment, two cycles of Amberlite CG-50 chromatography, and SP-Sephadex C-50 chromatography. Homogeneity of the preparation was demonstrated by three electrophoretic techniques. PS17-lysozyme behaved like a basic protein (pI, 9-10) consisting of a single polypeptide chain (molecular weight, 24, 500) and showed the substrate specificity of an N-acetyl-muramidase, i.e., the same specificity as hen egg-white lysozyme. The enzyme exhibited much higher specific activity than the egg-white enzyme when assayed with chloroform-killed P. aeruginosa P14 as a substrate. These characteristics, as well as the amino acid composition, were very similar to those of PRI-lysozyme; a bacteriolytic enzyme produced in mitomycin C-induced P. aeruginosa P15 concomitantly with a phage-tail-like bacteriocin, pyocin R1 (Ochi et al. (1978) J. Biochem. 83, 727-736). However, the behavior of these two lysozymes from P. aeruginosa in Amberlite CG-50 chromatography and some other properties indicated that they were not identical, though they were similar. The results are in accord with the view that pyocin R1 may be a defective form of a bacteriophage closely related to but not identical with phage PS17.抄録全体を表示PDF形式でダウンロード (1294K) -
Yuko ODA, Ken-ichi KASAI, Shin-ichi ISHII1981 年 89 巻 1 号 p. 285-296
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーQuantitative affinity chromatography of concanavalin A (Con A) was studied in order to clarify its mechanism of saccharide binding. Another aim of this work was to confirm the validity of frontal affinity chromatography, which we have developed for the study of specific interactions, for multivalent systems. Since Con A exists as either a dimer or a tetramer, it is a suitable multivalent test system. Immobilized p-aminophenyl-β-D-glucopyranoside (AP β-G1c Sepharose) was prepared and the interactions of homogeneous preparations of Con A with this affinity adsorbent were analyzed. Experiments were carried out under conditions where Con A exists as the dimer (5°C, pH 7.9, 1=0.19). The intrinsic dissociation constant of Con A for the immobilized ligand (Kd) could be determined from the extent of retardation. α-Con A (intact Con A) had a stronger affinity than β-Con A. Changes in pH and ionic strength had different effects on the affinity of α- and β-Con A. The dissociation constants of soluble saccharides and their derivatives (counter ligands) for Con A (K1) could be determined from their ability to diminish the elution volume of Con A. K1 values of various monosaccharides for β-Con A including those having very weak affinity, were determined. Further, the K1 values of a series of glucobioses were determined and compared. It was found that the binding mode of the reducing terminal glucose residue must be taken into account. The results are discussed in relation to their configurations. Frontal affinity chromatography proved to be very useful as a tool to analyze specific interactions in multivalent systems.抄録全体を表示PDF形式でダウンロード (837K) -
Masaaki KURODA, Takeshi TANAKA, Tomoh MASAKI1981 年 89 巻 1 号 p. 297-310
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーA new protein component of the Z-line of striated muscles was isolated from chicken breast muscle. This protein has been designated as eu-actinin because of its close similarity in polypeptide molecular weight to actin. Eu-actinin was extracted from myosin-removed myofibrils at low ionic strength at pH 6.5 and purified by column chromatography on Sepharose 4B and DEAE-cellulose. Although the polypeptide molecular weight of eu-actinin measured by SDS-polyacrylamide gel electrophoresis is similar to that of actin, other physico-chemical properties of eu-actinin definitely differ from those of actin. The isoelectric point of eu-actinin was more acidic than that of actin. The amino acid composition of eu-actinin was found to be different from that of actin or those of other muscle structural proteins. The results of analytical gel filtration on Sepharose 4B indicated that eu-actinin forms dimers through non-covalent bonding under aqueous conditions. Eu-actinin has a low axial asymmetry under low-salt conditions, as judged from its intrinsic viscosity ([η]=6.4ml/g for the dimer state) and exhibits a tendency to undergo self-association with increasing ionic strength.
Interactions of eu-actinin with other muscle proteins were examined by the affinity column technique. It was shown that eu-actinin binds to actin and α-actinin. Eu-actinin exhibited strong seeding ability for the polymerization of actin.
Antibody to eu-actinin was raised in a goat and purified by affinity chromatography. The specific antibody against eu-actinin did not form precipitine lines with actin or α-actinin. Immunofluorescence studies revealed that eu-actinin is localized at the Z-line of myofibrils. The FITC-conjugated antibody to eu-actinin also stained the Z-lines of rabbit skeletal muscle and chicken cardiac muscle. Therefore, it was concluded that eu-actinin is a new, ubiquitous constituent of Z-lines of striated muscles.抄録全体を表示PDF形式でダウンロード (2834K) -
Sadao YASUGI, Takeo MIZUNO1981 年 89 巻 1 号 p. 311-315
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーAn embryo-specific pepsinogen was isolated from the proventriculi of 15-day-old chicken embryos and purified by means of fractionation with ammonium sulfate, filtration on Sephadex G-100, and chromatography on DEAE-Sepharose CL-6B and hydroxyapatite. The properties of this pepsinogen and pepsin derived from it were compared with those of an adult-specific chicken pepsinogen and its pepsin. Though the optimal pH and alkali-stability were similar in the two pepsinogens, molecular weight, sensitivity to pepstatin, and antigenicity were quite different. Among the properties of this embryo-specific pepsinogen, the large molecular weight (56, 000 for pepsinogen and 53, 000 for pepsin) is especially noteworthy, since the molecular weights of the known pepsinogens of mammals and birds fall into the range of 35, 000-48, 000.抄録全体を表示PDF形式でダウンロード (1910K) -
Koscak MARUYAMA, Naotoshi MIMURA, Akira ASANO1981 年 89 巻 1 号 p. 317-319
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーActinogelin, a regulatory protein of cell motility, enhanced gelation of actin filaments in the absence of calcium ions, only on standing still or with very low velocity gradients (<0.1 s-1). The Ca2+-sensitive action of actinogelin on actin filaments was dependent on a weak external force. In the presence of a micromolar level of Ca2+, actinogelin did not affect the network formation of actin filaments at all.抄録全体を表示PDF形式でダウンロード (175K) -
Koui TAKAHASHI, Fumio NAKAMURA, Akio INOUE1981 年 89 巻 1 号 p. 321-324
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーPostmortem changes in the actin-myosin interaction were studied by determining the amount of thick and thin filaments dissociated by ATP. The amount of separated filaments was very small in myofibrils prepared from muscles in rigor, while it increased markedly during post-rigor storage of muscles. Electron microscopically, separated thick and thin filaments prepared from stored muscles were similar to freshly prepared ones and no signs of proteolytic degradation of either type of filament could be observed. A protein which was released from myofibrils (probably from Z discs) on Ca2+-treatment seemed to be most closely related to the postrigor dissociation of thick filaments from thin filaments.抄録全体を表示PDF形式でダウンロード (1579K) -
Takahisa HAYASHI, Yoji KATO, Kazuo MATSUDA1981 年 89 巻 1 号 p. 325-328
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーHydrolysis of the total non-cellulosic 14C-polysaccharides from soybean cell wall with carbohydrate hydrolases of an Aspergillus oryzae enzyme preparation yielded 14C-monosaccharides and [14C]isoprimeverose (6-O-α-D-xylopyranosyl-D-gluco-pyranose) in which all of the xylosyl residues of the xyloglucan were recovered. Based on this finding, an assay method for the activity of xyloglucan xylosyltrans-ferase was developed.
When UDP-[14C]xylose was incubated with a particulate enzyme fraction from soybean cells, radioactive polymers were synthesized. On digestion with the A. oryzae enzyme preparation, the product gave 14C-monosaccharides and [14C]isoprimeverose. This result suggests that the activity of xyloglucan xylosyltransferase can be distinguished from other polysaccharide synthase activities.抄録全体を表示PDF形式でダウンロード (1031K) -
Koichi MIZUNO, Motoko KOYAMA, Hiroh SHIBAOKA1981 年 89 巻 1 号 p. 329-332
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーA new method for isolating plant tubulin was devised. The method involves affinity chromatography with ethyl N-phenylcarbamate and Sepharose. The protein isolated by the affinity chromatography and purified by two successive chromato-graphical steps on DEAE-Sephadex A-50 and Sephadex G-200 consisted of two subunits which possessed the same mobilities as the α- and β-subunits of rabbit brain tubulin on SDS-polyacrylamide gel electrophoresis and showed colchicine-binding activity.抄録全体を表示PDF形式でダウンロード (1383K) -
Yasuhiro SUZUKI, Seiji NAGAO, Kuniya ABE, Tamio HIRABAYASHI, Yoshio WA ...1981 年 89 巻 1 号 p. 333-336
発行日: 1981年
公開日: 2008/11/18
ジャーナル フリーWe previously isolated a Ca2+-binding protein from a ciliate, Tetrahymena, and designated it as TCBP (Tetrahyinena Ca2+-binding protein). The present paper reports that TCBP, which has two high affinity Ca2+-binding sites (Kd=4.6×l0-6M), could activate porcine brain cyclic nucleotide phosphodiesterase at a concentration of over l0-6M free Ca2+, with the same mode of activation as that of authentic (porcine brain) calmodulin. In addition, the amino acid composition of TCBP was essentially the same as that of brain calmodulin. Therefore, we conclude that TCBP as an activator of Tetrahymena guanylate cyclase is indeed a calmodulin.抄録全体を表示PDF形式でダウンロード (957K)
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