巻号一覧
95 巻, 6 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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Setsuko YOKOTA, Katsuro URATA, Toshio SATOH1984 年 95 巻 6 号 p. 1535-1541
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーIn order to identify the b-type cytochrome involved in the nitrate reduction in a photodenitrifier, Rhodopseudomonas sphaeroides forma sp. denitrificans, the b-type cytochromes in the spheroplast membranes were characterized. Difference spectra at 77 K of spheroplast membranes indicated the presence of two b-type cytochromes with α bands at 556.5 and 562 nm. Three components considered to be of the b-type cytochrome were resolved by anaerobic potentiometric titration at 560-572 nm. Their midpoint potentials at pH 7, Em, 7, were -135 mV, +40 mV and +175 mV and their approximate reduced minus oxidized maxima were determined to be at 565 nm (562 nm at 77 K), 560 nm (556.5 nm) and 560 nm (556.5 nm), respectively. These values are almost the same as those reported for R. sphaeroides. The Em, 7 value of the cytochrome c involved in the nitrate reductase of this denitrifier was determined to be 250 mV. A b-type cytochrome reduced with NADH and FMN was oxidized by nitrate in chromatophore membranes. The possibility that cytochrome b (Em, 7=175 mV) is involved in the nitrate reduction is discussed.抄録全体を表示PDF形式でダウンロード (572K) -
Yasuhiro HASHIMOTO, Mikiko ABE, Yoshihiro KIUCHI, Akemi SUZUKI, Tamio ...1984 年 95 巻 6 号 p. 1543-1549
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーGM 2 containing NeuGc was a major ganglioside in the liver of mouse strains such as BALB/c, DBA/2, C3H/He, and C57BL/10, whereas WHT/Ht mouse liver did not contain GM2 (NeuGc) but contained GM3 (NeuGc) as a major ganglioside. Since GM3 (NeuGc) is a biosynthetic precursor of GM2 (NeuGc), WHT/Ht liver was considered to lack the ability to synthesize GM2 (NeuGc) from GM3 (NeuGc) (Hashimoto, Y., et al. (1983) J. Biochem. 93, 895-901). In this study we measured the activity of UDP-N-acetylgalactosamine: GM3 (NeuGc) N-acetylgalactosaminyl-transferase in the liver of BALB/c, WHT/Ht, and their progeny. The transferase activity in the microsomal fraction of BALB/c liver was 2.10±0.32×10-5 units/mg protein (mean ±S. D.), whereas no activity was detected in that of WHT/Ht liver. F1 hybrids between BALB/c and WHT/Ht expressed GM2 (NeuGc) as well as the enzyme activity, the level of which was almost half that in BALB/c liver (1.10±0.12×10-5 units/mg protein). The backcross generation of F1 to WHT/Ht segregated into two groups with respect to expression of GM2 (NeuGc) and the transferase activity: 11 of the 21 mice analyzed expressed both GM2 (NeuGc) and the transferase activity (1.28±0.18×10-5 units/mg protein), whereas the rest expressed neither. These results suggest that the expression of GM2 (NeuGc) is directly regulated by the activity of UDP-N-acetylgalactosamine: GM3 (NeuGc) N-acetylgalactosaminyltransferase in mouse liver.抄録全体を表示PDF形式でダウンロード (1358K) -
Taro NAKAMURA, Kenichi FUJITA, Yoshitomo EGUCHI, Michio YAZAWA1984 年 95 巻 6 号 p. 1551-1557
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーCalmodulins were isolated from vegetative mycelia of Basidiomycetes fungi, Agaricus campestris and Coprinus lagopus. These calmodulins showed similar mobilities to those of animal calmodulins on nondenaturing polyacrylamide gel electrophoresis in the presence or absence of Ca2+. The molecular weights of both calmodulins were determined to be 16, 000. Agaricus calmodulin consisted of 148 amino acids including ε-N-trimethyllysine and cysteine. The UV-absorption spectrum showed the relatively high content of phenylalanine in Basidiomycetes calmodulins. The difference UV-absorption spectrum due to the blue shift by Ca2+ was observed. Both calmodulins activated muscle myosin light chain kinase and pea NAD+ kinase in a Ca2+-dependent manner, and the activities were inhibited by trifluoperazine or chlorpromazine.
A calmodulin-like protein was partially purified from baker's yeast, Saccharomyces cerevisiae. However, detection of a calmodulin-like protein in prokaryotes was not successful.抄録全体を表示PDF形式でダウンロード (1064K) -
Kinuko KIMURA, Keiko YAGI, Kouji MATSUOKA1984 年 95 巻 6 号 p. 1559-1567
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーGlutamine synthetase from a Gram-positive acid-fast bacterium, Mycobacterium smegmatis, was purified to homogeneity from cells grown with glycerol-bouillon medium. Electron micrographs of the enzyme revealed a dodecameric arrangement of its subunits in two superimposed hexagonal rings, similar to the structure of glutamine synthetase of Escherichia coll. Disc electrophoresis in the presence of sodium dodecyl sulfate indicated a subunit molecular weight of 56, 000. The sedimentation coefficient of the native enzyme was estimated to be 19.45 by ultracentrifugation in a sucrose gradient.
Like the E. coli enzyme, the glutamine synthetase from M. smegmatis is regulated by adenylylation/deadenylylation. This conclusion was based on studies of the effect of snake venom phosphodiesterase treatment on the catalytic and spectral properties of the isolated enzyme. The AMP released from the enzyme by the phosphodiesterase was identified by thin-layer chromatography.
Despite the structural similarity of both enzymes, striking differences were found between the catalytic properties of M. smegmatis and E. coli glutamine synthetases. The divalent cation specificity of the M. smegmatis enzyme was not altered by adenylylation of the enzyme, and deadenylylation of the enzyme caused a significant increase in the specific activities for both biosynthetic and transfer reactions with either Mg2+ or Mn2+.抄録全体を表示PDF形式でダウンロード (1474K) -
Tomoko KOMIYAMA, Makoto MIWA, Tetsuo YATABE, Hiroshi IKEDA1984 年 95 巻 6 号 p. 1569-1575
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThermal denaturation of Streptomyces subtilisin inhibitor was studied by means of circular dichroism (CD) measurements in the far-UV and near-UV regions. The denaturation was found to be largely reversible; the partial irreversibility was associated with a slight loss of the inhibitory activity. Difference CD spectra in the far-UV region clarified the existence of two distinct steps in the thermal transition of the secondary structure. The first step below 80°C is attributable to a partial conformational change in the α-helix portion, whereas the second step between 80°C and 94°C is attributable to a major conformational change involving the β-sheet portion. On the assumption that the major denaturation involves dissociation of the SSI into its subunits, the enthalpy and entropy changes were determined to be 216 kcal•mol-1 and to be 603 cal•deg-1•mol-1, respectively.抄録全体を表示PDF形式でダウンロード (498K) -
Umeji MURAKAMI, Koki UCHIDA1984 年 95 巻 6 号 p. 1577-1584
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA two-dimensional electrophoresis procedure for the separation and analysis of troponin subunits is described in which the protein solution supplemented with 50mM each of both glutamic and aspartic acids is subjected to nonequilibrium pH gradient electrophoresis in the first dimension. Complete dissolution and gelation of the sample with agarose are essential for analysis of constituent proteins of cardiac myofibrils. Electrophoresis in the first dimension gel is carried out for a relatively short time, 2-3 h. In combination with sodium dodecyl sulfate slab gel electrophoresis (second dimension), three subunits, troponin T, troponin I, and troponin C, of dog cardiac troponin-tropomyosin complex and myofibrils can be simultaneously analyzed quantitatively on a slab gel. The contents of troponin and tropomyosin of cardiac myofibrils were 275±34 pmol/mg of myofibrillar protein. The molar ratio of troponin T, troponin I, troponin C, and tropomyosin was close to 1:1:1:1 in troponin-tropomyosin complex and myofibrils.抄録全体を表示PDF形式でダウンロード (1576K) -
Toshihiro TSUDZUKI1984 年 95 巻 6 号 p. 1585-1592
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe dopamine (DA)-translocating mechanism of synaptic vesicles isolated from rat brain has been studied in the presence of an artificially imposed ΔpH on the vesicle membranes (acidic inside with respect to the external medium) without the aid of ATP-Mg2+. Under the experimental conditions, [3H] DA uptake by the synaptic vesicles was driven by two different, i.e. ΔpH-dependent and -independent processes. Both processes appeared to be carrier-mediated based on the inhibition by NEM (N-ethylmaleimide), an -SH reagent, and by nomifensine, a DA uptake blocker at nerve terminals. The DA carrier of the vesicles was similar to that of the nerve terminal plasma membrane with respect to their susceptibility to nomifensine. The ΔpH-dependent uptake was transient and most of the incorporated DA was easily lost from the vesicles. On the other hand, the ΔpH-independent uptake increased with time and the amine was retained in the vesicles. The initial rate of the ΔpH-independent uptake was lower than that of the ΔpH-dependent one but their extents were comparable with each other. These results indicate that rat brain synaptic vesicles have a DA uptake system requiring no ATP hydrolysis.
A preparation of synaptic vesicles used here exhibited an inwardly directed proton translocation in the presence of ATP-Mg2+ when monitored by following changes in the fluorescence of ANS (8-anilino-1-naphthalene sulfonate). However, the time course of the ΔpH-generation was not influenced by the addition of 1mM DA. Therefore these results suggest that there is no close correlation between the active proton translocation and the DA uptake in synaptic vesicles. Since the vesicle preparation was usually contaminated with a small amount of mitochondrial membrane fragments judging from the presence of respiratory chain-cytochromes, the active proton translocation might be at least partially due to the contaminating submitochondrial particles.抄録全体を表示PDF形式でダウンロード (660K) -
V. Effect of Phospholipase C Treatment on the Binding Activities of the Fc Receptor of Macrophage or Its Isolated Plasma MembraneYoshitomi AIDA, Mari ITONAGA, Kaoru ONOUE1984 年 95 巻 6 号 p. 1593-1602
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe effect of phospholipase C treatment on the binding activity of the Fc receptor of guinea pig macrophage was studied to analyze the interaction of the Fc receptor with membrane phospholipids necessary for the activity. It was confirmed by subcellular fractionation that the receptor is localized on the plasma membrane. Treatment of the whole cell or isolated plasma membrane with phospholipase C of Clostridium perfringens diminished the binding of soluble IgG2-immune complex to Fc receptors on the cell or membrane. On the other hand, phospholipase C of Bacillus cereus did not affect the activity when it acted on the whole cell but it did diminish the activity when it acted on the isolated plasma membrane. Analysis of the phospholipids of untreated and treated macrophages or plasma membrane showed that phosphatidylcholine molecules, particularly those located in the membrane (not accessible to attack from the cell surface by phospholipase C of B. cereus), appear to be crucial for efficient interaction of macrophage Fc receptors with immune complex. Ligand-binding experiments with macrophages showed that the diminished binding activity was due to a decrease of the avidity for immune complex, but did not seem to be due to a decrease in the number or affinity of Fc receptors for monomeric IgG2. Taken together with the previous results which demonstrated that Fc receptors which had apparently lost the activity due to delipidation could be reconstituted with phosphatidylcholine but not with most other phospholipids, the results seem to indicate that the diminution of the binding activity to the immune complex of macrophage or its plasma membrane caused by phospholipase C treatment is due to the impairment of multivalent interaction between Fc receptor molecules on the membrane and IgG2 molecules in the immune complex, probably as a result of the loss of interaction of the head groups of phospholipids with Fc receptor molecules and the change in membrane properties resulting from the increase of diglycerides.抄録全体を表示PDF形式でダウンロード (800K) -
Takashi TAKAGI, Kazuhiko KONISHI1984 年 95 巻 6 号 p. 1603-1615
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe isotypes of sarcoplasmic Ca2+ binding protein (SCP) were purified from shrimp tail muscle. SCP exists in a dimeric form. One sample of shrimp contained only αA chain, whereas another contained αB and β chains, and a heterodimer of αBβ which was not analyzed precisely. The amino acid sequences of the two α chains were determined. The two a chains are composed of 190 and 192 amino acid residues, respectively. The sequences of the two α chains differed in only four amino acids out of 192 residues. The sequences indicate that the α chain has three Ca2+-binding sites which are common to EF-hand type Ca2+-binding protein. In the absence of added Ca2+ and Mg2+, the amounts of bound Ca2+ in αA, αB, and β chains were 3.0, 3.3, and 2.4 mol/22, 000g protein, respectively. Thus, it is suggested that all three isotypes of shrimp SCP have three Ca2+-binding sites which have high affinity to Ca2+. The sequence homology of shrimp SCP with other EF-hand type Ca2+-binding proteins is very low. The protein having the greatest homology with this SCP was cod parvalbumin; the sequence homology is 18%.抄録全体を表示PDF形式でダウンロード (2234K) -
Seiichiro MORI, Yasutaka KOZAKI, Munetoshi KATO, Atsushi TENDO, Yoshio ...1984 年 95 巻 6 号 p. 1617-1623
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーTryptic hydrolysis of benzoyl-DL-arginine p-nitroanilide was competitively inhibited by phenyl and substituted phenyl esters of trans-4-guanidinomethylcyclohexanecarboxylic acid (GMCHA), amidinopiperidine-4-carboxylic acid (APCA), amidinopiperidine-3-carboxylic acid (AP3CA), amidinopiperidine-4-acetic acid (APAA), amidinopiperidine-4-propionic acid (APPA), amidinopiperidine-3-propionic acid (AP3PA), amidinopiperidine-4-butyric acid (APBA), and amidinopiperidine-3-butyric acid (AP3BA). The 4-tert-butylphenyl (tBP) ester of APPA was the most effective inhibitor, its K1 value being 5.0×10-7M. The free acids and phenols had no inhibitory effect at 10-3M.
The tBP esters of GMCHA, APPA, and APBA caused 50-60% inhibition of growth of HeLa cells, their effects being dose-dependent, while same esters of APCA, AP3PA, APPA, AP3PA, and AP3BA inhibited the growth by 30-40%. The phenyl esters of these were less inhibitory than the tBP esters. A protease preparation obtained from HeLa cells by sonication and ultrafiltration through a molecular sieve membrane strongly hydrolyzed the fluorescent peptides Boc-Val-Pro-Arg-MCA and Bz-Arg-MCA. This proteolytic activity was not affected by soybean trypsin inhibitor but was strongly inhibited by the tBP esters of GMCHA, APAA, and APBA, their effects roughly paralleling their inhibitions of the growth of HeLa cells.抄録全体を表示PDF形式でダウンロード (559K) -
Ken OKABAYASHI, Eizo NAKANO1984 年 95 巻 6 号 p. 1625-1632
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーPurification and characterization of mitochondrial malate dehydrogenase [EC 1. 1. 1. 37] from unfertilized eggs of the sea urchin, Anthocidaris crassispina, are described. The purification method consisted of dextran sulfate fractionation, Blue Dextran Sepharose chromatography, Phenyl-Sepharose hydrophobic chromatography and DEAE-cellulose chromatography. The enzyme was purified 771-fold with a 7% yield from the crude extract. The purified enzyme appeared homogeneous on polyacrylamide gel electrophoresis under both native and denatured conditions. After incubation at 45°C for 50min, the enzyme lost about 90% of its activity. In the presence of NADH, however, the enzyme was protected against the heat denaturation. The native enzyme had a molecular weight of about 65, 000 and probably consisted of two identical subunits. In the reduction of oxaloacetate with NADH, a broad optimum pH ranging from 8.2 to 9.4 was found with 50mM Tris-HCl and glycine-NaOH buffers. Sodium phosphate buffer apparently activated the enzyme. The apparent Km values for oxaloacetate and NADH were 19 μM and 30 μM, respectively. The optimum pH for malate oxidation with NAD+ was 10.2 in 50mM NaHCO3-Na2CO3 buffer. The apparent Km values for malate and NAD+ were 7.0mM and 0.6mM, respectively. Zinc ion, sulfite ion, p-chloro-mercuriphenylsulfonate and adenine nucleotides strongly inhibited the enzyme.抄録全体を表示PDF形式でダウンロード (1315K) -
Yasuki HAMAZUME, Tomohiro MEGA, Tokuji IKENAKA1984 年 95 巻 6 号 p. 1633-1644
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーWhite- and Yolk-riboflavin binding proteins were isolated from hen eggs, and characterized as to their chemical properties. White- and Yolk-RBPs had almost same amino acid compositions except for glutamic acid, but their carbohydrate compositions were different from each other.
The complete amino acid sequence of White-RBP was determined by conventional methods. White-RBP comprised 219 amino acid residues, and the aminoterminus was pyroglutamic acid (pyrrolidonecarboxylic acid). Two amino acids, lysine and asparagine, were found at the fourteenth residue from the amino-terminus. Carbohydrate chains were linked to asparagine residues at positions 36 and 147.
Both White- and Yolk-RBPs were phosphorylated. In White-RBP either six or seven of nine serine residues between Ser (185) and Ser (197) were phosphorylated. The amino acid sequences around phosphoserines showed that phosphorylation might occur at a serine residue in one of the following sequences; Ser-X-Glu or Ser-X-Ser (P).抄録全体を表示PDF形式でダウンロード (1437K) -
Takashi KATSU, Shuichi YOSHIMURA, Tomofusa TSUCHIYA, Yuzaburo FUJITA1984 年 95 巻 6 号 p. 1645-1653
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe temperature dependence of the action of polymyxin B on Escherichia coli was studied by using K+, Ca2+, and tetraphenylphosphonium (TPP+) ion-selective electrodes. At room temperature (27°C), Ca2+ was released immediately after addition of polymyxin, while the efflux of K+ occurred after 30 s. The rapid release of Ca2+ was not affected by incubation temperature, while the efflux of K+ was significantly lowered at temperatures below about 25-30°C. The uptake of TPP+ also increased after polymyxin addition. The release of Ca2+ and the uptake of TPP+ supported the disruption of the outer membrane structure reported previously. In experiments with isolated membrane vesicles (the cytoplasmic membrane being exposed), the efflux of K+ was not delayed, but was lowered at temperatures below about 15-20°C. This temperature range differed significantly from that of whole cells, and was interpreted as representing a difference in membrane fluidity between the outer and cytoplasmic membranes. The phase transition temperature of the outer membrane is known to be higher than that of the cytoplasmic membrane; and the temperature dependence of efflux of K+ from membrane vesicles was compatible with the phase transition temperature of liposomes prepared with phospholipids (not containing lipopolysaccharides) extracted from E. coli. Thus, it was speculated that, with whole cells, polymyxin molecules passed through the outer membrane at temperatures above the phase transition and reached the cytoplasmic membrane, increasing its K+ permeability. The mechanism of the permeability change is discussed in terms of deformation of the cytoplasmic membrane structure induced by polymyxin molecules.抄録全体を表示PDF形式でダウンロード (764K) -
Osamu HOSOMI, Akira TAKEYA, Tadahisa KOGURE1984 年 95 巻 6 号 p. 1655-1659
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーHuman serum was shown to contain N-acetyllactosamine: N-acetylglucosaminyltransferase activity. The reaction product was hydrolyzed by β-N-acetylglucosaminidase and released [14C]N-acetylglucosamine, indicating that the N-acetylglucosaminyl residue was β-linked to N-acetyllactosamine. Methylation and hydrolysis of the reaction product yielded 2, 4, 6-trimethyl [3H] galactose, indicating that the N-acetylglucosaminyl residue was introduced at position C-3 of the terminal galactose of N-acetyllactosamine. In our experiments, 2, 3, 4-trimethyl[3H]galactose was not detected. Substrate competition studies between N-acetyllactosamine and lactose showed that this enzyme also catalyzed the transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to lactose. Since the Km value for N-acetyllactosamine, which was 7.0mM, was approximately a fourth of that for lactose (29.8mM), N-acetyllactosamine was more effective than lactose as an acceptor.抄録全体を表示PDF形式でダウンロード (1174K) -
Mitsushi INOMATA, Minoru NOMOTO, Masami HAYASHI, Megumi NAKAMURA, Kazu ...1984 年 95 巻 6 号 p. 1661-1670
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーTwo distinct calcium-dependent neutral proteases (CANPs) with different sensitivities to calcium ions were purified concurrently by almost the same procedures from rabbit skeletal muscle and their enzymatic properties were compared (sensitivity to various divalent metal ions, the pH dependency and heat-stability of the activity, and the hydrolytic activity towards various substrates). They were further compared chemically in terms of the state of thiol groups, the amino acid compositions of subunits and the peptide fragments by digestion with S. aureus V 8 protease.
The low calcium requiring form of CANP (μCANP) was more sensitive to other divalent metal ions such as Sr2+ and Ba2+ than the high calcium requiring form of CANP (mCANP). The comparison of the pH dependency of these μCANP activities showed that μCANP was active in a broader pH range than mCANP and the former was more heat-stable than the latter. Both CANPs had similar affinity to various substrates, but the hydrolytic velocity was several times higher with μCANP than with mCANP. Although they were inhibited by thiol protease inhibitors to the same extent, the states of thiol groups in them were quite different. The thiol group involved in the catalytic activity of the enzyme was exposed without adding Ca2+ in μCANP, whereas the group in mCANP became exposed only when sufficient Ca2+ was added. The large subunits of these two CANPs were different in their amino acid compositions and in the peptide fragment patterns produced by S. aureus V 8 protease but the small subunits were indistinguishable from each other. These results led us to conclude that these two CANPs are quite different in nature and are not in a simple relationship, i.e., one of them is not derived from the other by autolysis or modification.抄録全体を表示PDF形式でダウンロード (1300K) -
Osamu ITASAKA, Taro HORJ, Kimiko SASAHARA, Yaeko WAKABAYASHI, Fumiko T ...1984 年 95 巻 6 号 p. 1671-1675
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA simple and efficient method for the separation of phosphosphingolipids including phosphonosphingolipids by high-performance liquid chromatography is described. A mixture of authentic lipids consisting of sphingomyelin, ceramide phosphorylethanolamine, ceramide 2-aminoethylphosphonate, and ceramide N-methylaminoethylphosphonate was completely separated using a silica gel (Zorbax SIL) column with acetonitrile-methanol-water 72:40:10 (v/v) as eluting solvent. The elution of these sphingolipids was monitored directly with an ultraviolet spectromonitor at 207 nm. The practical limit of detection of each sphingolipid was about 0.2 μg or 0.3 nmol. Using this method, we found that from one to four different phosphono- and/or phosphosphingolipids in fresh-water shellfish can be routinely identified and reproducibly quantified.抄録全体を表示PDF形式でダウンロード (385K) -
Hiro-omi WATABE, Takehiko SHIBATA, Tohru IINO, Tadahiko ANDO1984 年 95 巻 6 号 p. 1677-1690
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA site-specific endonuclease (Endo. Sce I) which caused double-strand scission of DNA was highly purified from a eukaryote, Saccharomyces cerevisiae IAM4274. The molecular weight of the active form of Endo. Sce I was estimated to be 120, 000 and 110, 000 by sedimentation analysis on a glycerol density gradient and gel filtration on Ultrogel AcA34, respectively. Analysis of the fractions from the last column chromatography by polyacrylamide gel-electrophoresis in the presence of sodium dodecyl sulfate and by an assay of the endonucleolytic activities suggested that Endo. Sce I consists of two non-identical subunits with molecular weights of 75, 000 and 50, 000. Unlike restriction endonucleases, Endo. Sce I was active on chromosomal DNA of the cells which produced Endo. Sce I. Single-stranded DNA was not cleaved by Endo. Sce I, but inhibited the endonucleolytic activity of the enzyme on doublestranded DNA. The endonucleolytic activity of Endo. Sce I required the magnesium ions (Mg2+) as a sole cofactor; Mg2+ could not be replaced by Ca2+ or Zn2+. When Mg2- was replaced by manganese ions (Mn2+), extensively purified Endo. Sce I cleaved double-stranded DNA at many other sites in addition to the sites at which DNA was cleaved in the presence of Mg2+ Experiments indicated that this is not the activation of contaminating endonuclease in the preparation of Endo. Sce I, but the result of relaxation in the site-specificity of cleavage.抄録全体を表示PDF形式でダウンロード (5550K) -
Toshikazu NAKAMURA, Satoshi KATO, Akira ICHIHARA1984 年 95 巻 6 号 p. 1691-1696
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe short-term controls of glycogen synthase [EC 2. 4. 1. 11] and glycogen phosphorylase [EC 2. 4. 1. 1] by major regulators, such as insulin, glucose, catecholamine, and glucagon, were compared in a simple, yet organized experimental system, i.e., adult rat hepatocytes in primary culture. Glycogen synthase was activated by glucose markedly and dose-dependently (5-40mM), but insulin alone (1×10-8M) activated this enzyme only two-fold. Therefore, activation of the enzyme by the two regulators together was mostly due to activation by glucose. Glucagon at a concentration of 5×10-10M suppressed this activation almost completely. Glucagon at this concentration activated phosphorylase considerably and this activation was slightly inhibited by insulin. Phenylephrine also activated phosphorylase, and this activation was inhibited by phenoxybenzamine or prazosin, suggesting that activation by catecholamine is through the α1-adrenergic receptor. Similarly a high concentration of glucose diminished the effects of glucagon and phenylephrine. These results suggest that in rat liver, glycogen metabolism is controlled mainly by glucagon, catecholamine, and glucose; the former two activate phosphorylase and inactivate synthase, while glucose activates synthase strongly and inactivates phosphorylase partially. Insulin plays a minor role in both reactions. Thus, the liver is primarily an organ for glucose production, which is regulated by hormones, not for glycogen storage, which is increased only by a high glucose concentration in the portal blood.抄録全体を表示PDF形式でダウンロード (469K) -
Akira MURAYAMA, Fumio FUKAI, Takashi MURACHI1984 年 95 巻 6 号 p. 1697-1704
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーBasic estrogen receptor (ER) molecule (vero-ER) of the cytosol of porcine uterus was purified 1, 200-fold after successive chromatographies on phenyl-Sepharose, hydroxylapatite, and DEAE-cellulose, followed by Sephadex G-150 gel filtration. The purified vero-ER was completely free from endogenous protease and ER-binding factor. The action of Ca2+-dependent cysteine proteinase (calpain) on vero-ER was studied by utilizing the purified receptor and calpains from porcine uterus (endogenous calpain), porcine kidney, and human erythrocytes. Proteolysis of vero-ER was followed by monitoring the disappearance of the binding capability of vero-ER with “8 S” ER-forming factor. Vero-ER was proteolyzed by both the endogenous and the exogenous calpains in the presence of Ca2+. The calpains did not attack vero-ER in the absence of Ca2+. The results indicated the absolute requirement by calpain for Ca2+ for the limited hydrolysis of vero-ER. Uterine cytosol was shown to contain, in parallel with calpain, a protease which does not require Ca2+ for the limited proteolysis of vero-ER. The strongly hydrophobic domain of vero-ER, recently shown to be indispensable for the nuclear translocation of vero-ER (Murayama, A. & Fukai, F. (1983) FEBS Lett. 158, 255), was preferentially destroyed by both the Ca2+-requiring and -nonrequiring enzymes. It was assumed that calpain might intervene in the estrogen action by diminishing irreversibly the amount of the cytoplasmic ER capable of translocating into the nucleus.抄録全体を表示PDF形式でダウンロード (686K) -
II. Characterization of Fatty Acid Synthetase from Cephalosporium caerulensHiroshi TOMODA, Akihiko KAWAGUCHI, Satoshi OMURA, Shigenobu OKUDA1984 年 95 巻 6 号 p. 1705-1712
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーCerulenin, an antifungal antibiotic isolated from a culture filtrate of Cephalosporium
caerulens, is a potent inhibitor of fatty acid synthetase systems of various microorganisms and animal tissues. This antibiotic specifically blocks the activity of β-ketoacyl thioester synthetase (condensing enzyme) by binding to the functional cysteine-SH in the active center of the condensing enzyme domain (the peripheral SH-group). However, fatty acid synthetase from C. caerulens is much less sensitive to cerulenin than fatty acid synthetases from other sources. The properties of C. caerulens synthetase were investigated and compared to those of Saccharomyces cerevisiae synthetase, which is sensitive to the antibiotic. The molecular weight of the enzymically active form of C. caerulens synthetase was 2.53×106. The enzyme consisted of two multifunctional proteins, α and β, which are arranged in a complex, α6β6. The synthetase was inactivated by iodoacetamide. At 0°C and pH 7.15, the second-order rate constant of k=15.6M-1•s-1 was obtained for the inactivation by iodoacetamide. This value was about 15 times greater than that for S. cerevisiae synthetase. Treatment of C. caerulens synthetase with iodoacetamide, while impairing the synthetase activity, induced malonyl-CoA decarboxylase activity. When S. cerevisiae synthetase was preincubated with cerulenin, malonyl-CoA decarboxylase activity could not be detected even after treatment of the enzyme with iodoacetamide (Kawaguchi, A., Tomoda, H., Nozoe, S., Omura, S., & Okuda, S. (1982) J. Biochem. 92, 7-12). In the case of C. caerulens synthetase, on the other hand, malonyl-CoA decarboxylase activity was induced by iodoacetamide even after the preincubation of the enzyme with cerulenin. The amount of [3H]-cerulenin bound to C. caerulens synthetase was not enough to occupy all the functional cysteine-SH of the condensing enzyme domain. The results reported in this paper suggest that the low reactivity of the functional cysteine-SH with cerulenin plays an important role in the cerulenin resistance of this fungus.抄録全体を表示PDF形式でダウンロード (583K) -
III. Studies on Active-Site Peptides of Fatty Acid Synthetase from Cephalosporium caerulensHiroshi TOMODA, Akihiko KAWAGUCHI, Tadashi YASUHARA, Terumi NAKAJIMA, ...1984 年 95 巻 6 号 p. 1713-1723
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーActive-site peptides of acetyl transferase, condensing enzyme and acyl carrier protein in the neighborhood of the prosthetic group, 4'-phosphopantetheine, of Cephalosporium caerulens fatty acid synthetase were investigated. The enzyme was reacted with [14C] acetyl-CoA or [14C] iodoacetamide. 14C-Labeled enzyme was digested with pepsin, trypsin or both. 14C-Labeled peptides were isolated by several purification procedures. The amino acid sequence of the active site of condensing enzyme was determined to be Tyr-Gln-Val-Glu-Ser-Cys-Pro-Ile-Leu-Glu-Gly-Lys and that of acetyl transferase was Phe-Ser-Gly-Ala-Thr-Gly-His-Ser-Gln-Gly. The amino acid composition around the 4'-phosphopantetheine-carrying serine was determined to be Asx2, Thr, Ser, Glx3, Gly2, Ala, Ile, Leu3, and Lys. When these active-site peptides were compared with those of Saccharomyces cerevisiae synthetase, a high degree of homology was observed in the active-site peptides of the acetyl transferase and acyl carrier protein domains. However, that of the condensing enzyme domain gave lower homology. These findings may support the assumption that the low reactivity of cerulenin with C. caerulens synthetase is a consequence of the structure of the condensing enzyme domain.抄録全体を表示PDF形式でダウンロード (738K) -
Yasuhiro WATANABE, Yoshimitsu SHIMAMORI, Masakazu OZAKI, Masahide UCHI ...1984 年 95 巻 6 号 p. 1725-1732
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーAn endopeptidase which cleaves succinyl trialanine p-nitroanilide (Suc(Ala)3-pNA) into succinyl dialanine and alanine p-nitroanilide (Ala-pNA) was solubilized from a microsomal membrane fraction of rat kidney with Nonidet P-40 following treatment with 1M KCl and Brij 35. The solubilized enzyme was purified to homogeneity by DEAE-Sephadex chromatography, Sepharose CL-6B gel filtration and sucrose gradient centrifugation. The final enzyme preparation had a specific activity of 1.69 μmol/min/mg protein, representing about 140-fold purification over the starting membrane. The enzyme hydrolyzes Suc(Ala)3-pNA with a Km value of 0.28mM and a Vmax value of 1.3 μmol/min. The molecular weight of the undenatured enzyme was estimated to be 360, 000 by gel filtration on a Sepharose CL-6B column and that of the denatured enzyme to be 92, 000 by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, revealing the presence of a single polypeptide chain. The enzyme was markedly activated by polyamines, producing increases in the values of both Km and Vmax. Comparatively less activation was found in the presence of some monovalent cations and Ca2+. The activation by polyamines was inversely proportional to the concentration of monovalent cations, but Ca2+ and polyamines seemed to stimulate additively.抄録全体を表示PDF形式でダウンロード (583K) -
Emi KUSUNOSE, Masatoshi KAKU, Kosuke ICHIHARA, Satoru YAMAMOTO, Ikuya ...1984 年 95 巻 6 号 p. 1733-1739
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーMicrosomes from rabbit small intestine mucosa were found to catalyze the hydroxylation of PGA1 in the presence of NADPH. The major product was identified as 20-hydroxy PGA1 by using high performance liquid chromatography and gas chromatography-mass spectrometry, and the minor product was assumed to be 19-hydroxy PGA1. The ratio of the former product to the latter was about 24.1. The specific PGA1 ω-hydroxylase activity of small intestine microsomes was comparable to that of liver microsomes, and was significantly higher than those of microsomes from other tissues such as kidney cortex and lung. Microsomes from rabbit colon mucosa also catalyzed the hydroxylation of PGA1 in the presence of NADPH, with the ratio of ω- to (ω-1)-hydroxy PGA1 formed being 33.0. The PGA1 hydroxylase activities of the microsomes from both small intestine and colon were inhibited markedly by carbon monoxide, indicating the participation of cytochrome P-450. A cytochrome P-450 was solubilized from small intestine microsomes, and purified to a specific content of 10.5 nmol of cytochrome P-450/mg of protein. This cytochrome hydroxylated PGA1 at the ω-position with a turnover rate of 38.2 nmol/min/nmol of cytochrome P-450 in the reconstituted system containing cytochrome P-450, NADPH-cytochrome P-450 reductase, cytochrome b5 and phosphatidylcholine. It is suggested that this cytochrome P-450 is specialized for the ω-hydroxylation of PGA1 in small intestine microsomes.抄録全体を表示PDF形式でダウンロード (1278K) -
Tomoko HAYASHI, Hiroaki HAYASHI, Yukihiro FUSAUCHI, Koichi IWAI1984 年 95 巻 6 号 p. 1741-1749
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe H3 histone of the protozoan Tetrahymena pyriformis was obtained as described previously (Fusauchi, Y. & Iwai, K. (1983) J. Biochem. 93, 1487-1497) and further purified by Sephadex G-50 chromatography after reduction and carboxymethylation. The purified H3 was shown to comprise two variants, 75 mol% of H3(1) and 25 mol% of H3(2). The H3 mixture was directly sequenced by Edman degradation from the N-terminal through residue 104. Sequence determination was further performed with tryptic peptides and cyanogen bromide fragments derived from the H3 mixture. Thus, the total sequences of H3 (1) and H3 (2) were completely determined; both consist of a total of 135 amino acid residues (the molecular weights in the unmodified form are 15, 336 for H3 (1) and 15, 424 for H3 (2)), and both are partially acetylated or methylated at the same six lysine residues to similar extents. The H3(1) and H3 (2) sequences differ in 14 positions from each other, and in 17 and 21 positions from those of human spleen H3 (Ohe, Y. & Iwai, K. (1981) J. Biochem. 90, 1205-1211). The implications of these results for the structure-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 (1765K) -
Hiroyuki HASEGAWA, Mariko YANAGISAWA, Arata ICHIYAMA1984 年 95 巻 6 号 p. 1751-1758
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA rapid separation of 5-hydroxytryptophan by high performance liquid chromatography (HPLC) was achieved for the assay of tryptophan hydroxylase. “Bulk separation” of the product from all other components in the reaction mixture by HPLC was achieved by 1) the choice of a suitable column-solvent system so as to elute the reaction product ahead of other components in the sample mixture, 2) the use of a monitor selective for the reaction product, 3) minimization of the column length so as to achieve rapid separation of the product from the substrate. The method finally employed a reversed phase column of 5cm length, relatively rapid elution at 2 ml/min and fluorescence detection at 350 nm with an excitation at 302 nm. The assay is convenient and as sensitive as the radioisotope method. The advantages of the method are 1) almost no pretreatment of samples, 2) repeatability every 2min, 3) wide latitude of product determination from picomole to nanomole amounts per assay. The method was extended to the assay of 5-hydroxytryptophan decarboxylase by essentially the same procedures.抄録全体を表示PDF形式でダウンロード (728K) -
Aiko KITAHARA, Takashi SASAKI, Takanobu KIKUCHI, Noboru YUMOTO, Nagahi ...1984 年 95 巻 6 号 p. 1759-1766
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーLarge-scale purification of calpain [Ca2+-dependent cysteine proteinase; EC 3. 4. 22. 17] from porcine tissues is described. The methods used included chromatographies on DEAE-cellulose, Ultrogel AcA 34, Blue Sepharose CL-6B, and DEAE Bio-Gel A which yielded homogeneous enzyme proteins: 27.0mg of calpain I (low Ca2+-requiring form) from 5 liters of blood with 17, 900-fold purification and 57.6mg of calpain II (high Ca2+-requiring form) from 1.5kg of kidneys with 5, 800-fold purification. Porcine calpains I and II are half-maximally activated at 2.8 μM and 150 μM Ca2+, respectively. They are composed of large and small subunits: Mr 83, 000 and 29, 000 for calpain I and Mr 80, 000 and 29, 000 for calpain II. Gelelectrophoretic analysis of the digest with α-chymotrypsin or Staphylococcus aureus V8 protease revealed that the large subunits of calpains I and II are markedly different in structure whereas the small subunits are most likely identical. Monospecific antibodies directed toward the respective large and small subunits were used for immunoblotting experiments which established not only the identity among several porcine tissues of calpain I but also that of calpain II.抄録全体を表示PDF形式でダウンロード (2236K) -
Kenzo CHIBA, Takao OHYASHIKI, Tetsuro MOHRI1984 年 95 巻 6 号 p. 1767-1774
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーQuantitative analyses were carried out on Tb3+ binding to porcine intestinal calcium-binding protein (CaBP). Tb3+ (emission at 547 nm) and intrinsic tyrosine (emission at 303 nm) fluorescences upon excitation at 260 nm increase almost in parallel with increasing Tb3+ concentration up to a molar ratio of 2 against the protein in the CaBP solution. The pH dependence profile of Tb3+ fluorescence of the Tb3+-CaBP complex suggests that some free carboxylate groups are involved in the binding, as also suggested for Ca2+ binding. The results of fluorometric titration of Tb3+ and intrinsic tyrosine fluorescences of the CaBP complex with Tb3+ or Ca2+ led us to conclude that Tb3+ and Ca2+ have two common binding sites for each CaBP molecule. An equilibrium dialysis experiment showed that the dissociation constants of the two Tb3+-binding sites are 0.29 and 3.51 μM. Tb3+ strongly inhibits 45Ca binding to one of the two Ca2+-binding sites in the CaBP.
All of these and previous results indicate that each Tb3+ ion can bind to either of two high-affinity Ca2+-binding sites in porcine intestinal CaBP with an affinity different from that for Ca2+ ion. We discuss the localization of the Ca2+-and Tb3+-binding sites in the CaBP.抄録全体を表示PDF形式でダウンロード (527K) -
Yoshiro KOBAYASHI, Makoto ASADA, Toshiaki OSAWA1984 年 95 巻 6 号 p. 1775-1782
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーVarious hydroxyl radical scavengers markedly inhibited phorbol myristate acetate (PMA)-induced lymphotoxin (LT) production by a human T cell hybridoma, AC5-8. Among those we tested, tetramethylurea (TMU) was the most potent scavenger, and it was revealed that TMU must be added before 2 h have elapsed after PMA addition in order for LT production to be inhibited. In concordance with this fact, soluble NADPH dependent O2- forming enzyme (s) were activated several fold by PMA. PMA also induced DNA strand breaks, a process markedly inhibited by TMU. As expected, ADP-ribosyl transferase (ADPRT), which is well known to require DNA strand breaks for its enzymatic activity, was activated by PMA treatment. In addition, specific inhibitors for ADPRT, namely 3-amino-benzamide and nicotinamide, inhibited PMA-induced LT production. Taken together, these three successive events, activation of soluble NADPH dependent O2- forming enzyme (s), DNA strand breaks and activation of ADPRT, may be required for PMA-induced LT production by AC5-8.抄録全体を表示PDF形式でダウンロード (593K) -
Taibo YAMAMOTO, Robert E. YANTORNO, Yuji TONOMURA1984 年 95 巻 6 号 p. 1783-1791
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーSarcoplasmic reticulum (SR) isolated from rabbit muscle was treated with N-ethyl-maleimide (NEM) to specifically inhibit the dephosphorylation step of the Ca2+, Mg2+-dependent ATPase reaction. However, when this membrane was solubilized with dodecyl octaethyleneglycol monoether (C12E8), rapid decomposition of the phosphoenzyme (EP) was observed both in the absence and presence of Mg2+. When the detergent was removed from the reaction mixture, the inhibition of EP decomposition by NEM was observed again. These results support our previous suggestion (1, 2) that in the presence of high concentrations of C12E8, EP may be hydrolyzed to produce P1 in a manner different from the reaction in the native SR ATPase.
Gel filtration of the solubilized ATPase was performed in the presence of low concentrations of C12E8 to elute ATPase aggregates of various sizes. Two distinct fractions were selected after column chromatography and their physical and kinetic properties were compared. The molecular weights of the ATPase proteins of these two fractions were determined to be about 150 and 360 K daltons with Stokes radii of about 5.5 and 8.0 nm, respectively. The Stokes radii agreed with the values obtained from polarization decay measurement data of N-1-pyrene maleimide (N-1-P)-labeled ATPase aggregates separated on the same column.
The rate of EP decomposition was determined for the two column fractions described above. After the addition of EDTA the EP decomposition rate of the smaller-sized ATPase was much higher than the EP decomposition rate of the larger-sized ATPase. This finding also supports our previous conclusion (3) that a relationship exists between the oligomeric structure of the ATPase and its Mg2+ sensitivity in EP decomposition.抄録全体を表示PDF形式でダウンロード (658K) -
The Amino Acid Sequence of Coagulogen Isolated from Southeast Asian Horseshoe Crab, Tachypleus gigasToshiyuki MIYATA, Kazuko USUI, Sadaaki IWANAGA1984 年 95 巻 6 号 p. 1793-1801
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーThe amino acid sequence of coagulogen isolated from Southeast Asian horseshoe crab (Tachypleus gigas) has been determined. The NH2-terminal sequence of the first 51 residues was obtained by automated Edman degradation. The intact protein was then treated with a Tachypleus clotting enzyme, to form a gel and to remove an internal peptide C (28 residues) located near the NH2-terminal portion. The gel protein, which consisted of A chain (18 residues) and B chain (129 residues), was S-alkylated and the resulting two chains were separated by acetone precipitation. Among these segments, A chain and peptide C were assigned to the NH2-terminal portion of whole coagulogen, as judged from their amino acid compositions. On the other hand, the covalent structure of B chain was determined by sequencing the peptides obtained from its tryptic digest. The alignments of the tryptic peptides were deduced from the sequence homology, in comparison with the previously established B chain sequence of Japanese horseshoe crab (T. tridentatus) coagulogen. T. gigas coagulogen had a total of 175 amino acids and a calculated molecular weight of 19, 770.
When the sequence was compared with those of Japanese and American horseshoe crab (Limulus polyphemus) coagulogens, extensive structural homology was found: T. tridentatus/T. gigas, 87% and L. polyphemus/T. gigas, 67%. This comparison suggests that Japanese and Southeast Asian horseshoe crabs have a closer phylogenetic relationship with each other than with American horseshoe crab, based on amino acid sequence data. Moreover, the sequence comparison indicated that the A and B chain regions, which participate in the gel formation, have extremely high homology in the three coagulogens, whereas the peptide C region (released during the gelation) is relatively variable.抄録全体を表示PDF形式でダウンロード (1305K) -
Koei HAMANA, Shigeru MATSUZAKI, Kinji INOUE1984 年 95 巻 6 号 p. 1803-1809
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーPolyamines in various organs of larval, pupal, and moth stages of Bombyx mori, were assayed by high-performance ion-exchange chromatography and paper and thin-layer chromatography. Putrescine and spermidine were especially abundant in the silk gland, gonads, mucous gland, and sucking stomach; spermine was also present in them, but at much lower concentrations. Both norspermidine and norspermine were detected in almost all organs examined, while their precursor 1, 3-diaminopropane was found only in a limited number of organs. Low concentrations of sym-homospermidine were observed in the silk gland and ovary. Cadaverine content was particularly high in the mucous gland which contained diapause eggs and the sucking stomach. Diapause eggs contained much higher levels of cadaverine than non-diapause eggs. The concentrations of most polyamines in the silk glands remained rather constant during the larval stage, and decreased markedly at the pupal stage. Polyamines in gonads, in contrast, did not decrease at the pupal stage, but putrescine, diaminopropane, and norspermidine rather increased during the pupal and moth stages.抄録全体を表示PDF形式でダウンロード (533K) -
Mitsuhiro HATAKEYAMA, Yoriko TANIMOTO, Tadashi MIZOGUCHI1984 年 95 巻 6 号 p. 1811-1818
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA cytosol thioltransferase was purified 37, 000-fold from bovine liver by essentially the same procedure as reported for rat liver enzyme by Axelsson et al. ((1978) Biochemistry 17, 2978-2984). The purified enzyme appears to be homogeneous on sodium dodecyl sulfate (SDS)-gel electrophoresis and has a molecular weight (Mr) of 11, 000, an isoelectric point (pI) of 8.1, and an optimum pH with S-sulfocysteine and GSH as substrates of 8.5. It is specific for disulfides including L-cystine, S-sulfocysteine, ribonuclease A, trypsin, soybean Kunitz trypsin inhibitor, soybean Bowman Birk trypsin inhibitor and insulin, and converts Bowman Birk trypsin inhibitor to an inactive form.
The enzyme does not act as a protein: disulfide isomerase, as measured by reactivation of “scramble” ribonuclease and Kunitz soybean trypsin inhibitor. Thioltransferase activity was found in cytosol of various bovine tissues.抄録全体を表示PDF形式でダウンロード (588K) -
Hideyoshi YOKOSAWA, Makoto NISHIKATA, Shin-ichi ISHII1984 年 95 巻 6 号 p. 1819-1821
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーA peptide aldehyde inhibitor possessing prolinal at the carboxyl terminus was designed as an inhibitor of post-proline cleaving enzyme by analogy with peptide aldehyde inhibitors of serine and thiol proteases. N-Benzyloxycarbonyl-valyl-prolinal was found to be a potent inhibitor of post-proline cleaving enzyme from ascidian sperm with a K1 value of 2.4 nM. The presence of the aldehyde portion of the inhibitor, as well as its prolonged incubation with the enzyme, is indispen-sable for the potent inhibitory activity of the inhibitor. These results indicate that N-benzyloxycarbonyl-valyl-prolinal functions as a transition-state aldehyde inhibitor of post-proline cleaving enzyme.抄録全体を表示PDF形式でダウンロード (255K) -
Takayuki MIYANISHI, Takashi SAKU, Genji MATSUDA1984 年 95 巻 6 号 p. 1823-1826
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーAntibody was prepared against the 25, 000-dalton tryptic fragment of subfragment-1 from skeletal muscle myosin. The antibody was found to inhibit the Mg2+-ATPase activity and the initial P1-burst of the ATPase. The antibody suppressed the ATP-induced fluorescence enhancement of S-1, though it did not suppress the binding of ATP to S-1. The acto-S-1 ATPase activity was also inhibited by the antibody. These results suggest that there is a site in the 25K fragment region responsible for the transition of the myosin-ATP complex to another high energy complex.抄録全体を表示PDF形式でダウンロード (1070K) -
Noriaki SHIMIZU, Yoshihiro SOKAWA, Junko SOKAWA1984 年 95 巻 6 号 p. 1827-1830
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーUsing glycerol gradient centrifugation, the molecular sizes of porcine (2'-5') oligoadenylate synthetases (2-5A synthetases) were estimated. The 2-5A synthetase purified from pig spleen was about 150 kDa, while the enzyme extracted from nuclei of Newcastle disease virus-infected pig epithelial cells (SK-h) was about 20-40 kDa. The nuclear 2-5A synthetase was selectively adsorbed to Protein A-Sepharose beads conjugated with anti-spleen 2-5A synthetase antibody. Thus, the smaller 2-5A synthetase in nuclei of pig cells shares a protein structure with the larger enzyme from pig spleen.抄録全体を表示PDF形式でダウンロード (251K) -
1984 年 95 巻 6 号 p. 1831a
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (36K) -
1984 年 95 巻 6 号 p. 1831b
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (36K) -
1984 年 95 巻 6 号 p. 1831c
発行日: 1984年
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (36K)
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