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Volume 97 (1985)
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Volume 97, Issue 6
Displaying 1-38 of 38 articles from this issue
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Hiroyuki ARAI, Keizo INOUE, Yumiko NATORI, Yoshiko BANNO, Yoshinori NO ...1985 Volume 97 Issue 6 Pages 1525-1532
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPhospholipase activity was studied in the protozoan Tetrahymena pyriformis NT-1 by using exogenous phosphatidylethanolamine and phosphatidylcholine. Several phospholipase activities were found in Tetrahymena homogenates. They were distinguished with respect to pH optimum, activity dependence on Ca2+, substrate specificity and positional specificity. Ca2+-Dependent phospholipase activity had an optimal pH around 9 and gave rise to free fatty acid and lysophospholipid. This enzyme hydrolyzes phosphatidylethanolamine but not phosphatidylcholine. The alkaline phospholipase with Ai activity was located mainly in the surface membrane (pellicle fraction). The enzyme activity had a pH optimum ranging from 8 to 9, and required 2mM CaCl2 for the maximal activity. All detergents tested inhibited the enzyme activity. Ca2+-Independent phospholipase activity had an optimal pH from 4 to 5 and gave rise to free fatty acid, lysophospholipid, diacylglycerol, and monoacylglycerol. We concluded that there are at least three phospholipase in Tetrahymena homogenates, i.e., alkaline phospholipase A and acidic phospholipases A and C.View full abstractDownload PDF (597K) -
Toshiyuki CHIKUMA, Yoko ISHII, Takeshi KATO, Hiroaki KODAMA, Yoshiyuki ...1985 Volume 97 Issue 6 Pages 1533-1539
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe effects of prostaglandin E2(PGE2) on the degradation of collagen and noncollagenous peptides in clonal osteoblastic MC3T3-E1 cells were investigated by using highly sensitive assay methods for PZ-peptidase, collagenase-like peptidase (CL-peptidase), dipeptidyl-aminopeptidase (DAP), leucine aminopeptidase (LAP), and post-proline cleaving enzyme (PPCE). PGE2, at concentrations of 0.1 to 4.0 μg/ml, doubled the PZ-peptidase and CL-peptidase activities in the cells on 24h culturing in a dose-dependent manner. PGE2, at a concentration of 2.0 μg/ml, enhanced the specific activities of PZ-peptidase, CL-peptidase, DAP, LAP, and PPCE for 75h after the start of PGE2 stimulation. The time dependent changes in PZ-peptidase and CL-peptidase activities showed similar patterns, and 3- and 2-fold increases were seen after 48h, respectively. The protein and DNA contents gradually increased after addition of PGE2. Since the PZ-peptidase and CL-peptidase, involved in degradation of collagen peptides, were significantly induced by PGE2 in comparison with LAP and PPCE, involved in the degradation of noncollagenous peptides, these results show that PGE2 specifically stimulates induction of collagen catabolizing enzymes in clonal osteoblasts.View full abstractDownload PDF (562K) -
Makoto NISHIKATA1985 Volume 97 Issue 6 Pages 1541-1549
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe results of inhibition studies of soybean trypsin-like enzyme (STLE) by substrate analogues (derivatives of arginine) suggested that a net negative charge exists at or near the substrate binding region of the enzyme. On hydrolysis of substrates, this negative charge seems to repel the products from the substrate binding region and facilitate the turn-over of substrates. From the data on inhibition by various amidines, guanidines, and amines, some information about the structure of the hydrophobic binding pocket of STLE was obtained. The inactivation of STLE by irreversible inhibitors, diisopropylfluorophosphate (DFP) and tosyl-lysine chloromethyl ketone (Tos-Lys-CH2Cl), was decreased by competitive inhibitors. This means that these irreversible inhibitors bind with residues at the substrate binding region, probably serine and histidine residues, respectively.View full abstractDownload PDF (640K) -
Fumiyuki MITSUMORI1985 Volume 97 Issue 6 Pages 1551-1560
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA method to determine the intracellular pH of intact erythrocytes using phosphorus-31 nuclear magnetic resonance spectroscopy is described. Changes in phosphorus metabolites due to the alkalization of intracellular pH were also examined. The normal erythrocytes gave signals of phosphate groups corresponding to 2, 3-bisphosphoglycerate, inorganic phosphate, ATP, and NAD. Among them, the separation between α and γ peaks of ATP was shown to be a good indicator of the intracellular pH free from the perturbation caused by hemoglobin. This method enabled us to determine the intracellular pH of the erythrocytes without any pretreatment. The separation between α and γ peaks of ATP was also dependent on the degree of complexation with Mg2+, and was consistent with approximately 80% of total ATP complexing with Mg2+ in the samples investigated here. The pKa value of ATP in the erythrocytes was estimated to be 6.1 at 23°C, which is lower than the value of 6.5 obtained for the Mg2+-free ATP solution. In the alkalized erythrocytes, fructose 1, 6-bisphosphate and dihydroxyacetone phosphate were observed in addition to the metabolites found in the normal erythrocytes. Time course changes in these phosphorus metabolites were followed along with the intracellular pH monitored from ATP peaks.View full abstractDownload PDF (724K) -
Takanori NAKAMURA, Takashi MORITA, Sadaaki IWANAGA1985 Volume 97 Issue 6 Pages 1561-1574
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA proclotting enzyme associated with the hemolymph coagulation system of limulus (Tachypleus tridentatus) was highly purified from the hemocyte lysate. The first step of purification was performed by chromatography of the lysate on a pyrogenfree dextran sulfate-Sepharose CL-6B column, which was essential for separation of the proclotting enzyme from its activator, named factor B. The following steps consisted of column chromatographies on DEAE-Sepharose CL-6B, Sephadex G-150, benzamidine-CH-Sepharose and Sephacryl S-300. Through these procedures, 1.4 mg of the purified material was obtained from 630ml of the lysate and approximately 300-fold purification was achieved. The preparation gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the presence and absence of 2-mercaptoethanol. The single-chain proclotting enzyme was a glycoprotein with an apparent molecular weight of 54, 000, and no γ-carboxyglutamic acid was detected. The proclotting enzyme was converted to its active form by purified factor B or by trypsin. The resulting clotting enzyme had a molecular weight of 54, 000, consisting of a heavy chain of Mr=31, 000 and a light chain of Mr=25, 000. The serine active site of the clotting enzyme was found in the heavy chain. The chemical analyses of the isolated heavy and light chains indicated that the activation of the proclotting enzyme to its active form by factor B or trypsin is induced by a limited proteolysis, yielding two chains bridged by a disulfide linkage(s).View full abstractDownload PDF (2605K) -
Masato HIRATA, Masataka KUKITA, Toshiyuki SASAGURI, Eiichi SUEMATSU, T ...1985 Volume 97 Issue 6 Pages 1575-1582
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSInositol 1, 4, 5-trisphosphate (InsP3) releases Ca2+ from the non-mitochondrial Ca2+ store site of various types of cells. To study the mechanisms of the Ca2+ release from the store site, the effect of InsP3 on the passive Ca2+ release and influx, and the active Ca2+ uptake in the presence of oxalate, was examined using saponintreated guinea pig peritoneal macrophages. InsP3 stimulated the passive Ca2+ release and influx. Although InsP3 slightly inhibited the active Ca2+ uptake in the presence of oxalate, it seems unlikely that the Ca2+ release by this agent is caused by the inhibition of the Ca2+ uptake, because the addition of apyrase or hexokinase (which removes ATP within 30 s, so that no more Ca2+ can be accumulated) or vanadate (which inhibits the Ca2+ uptake) resulted in very slow release of Ca2+. These results suggest that the Ca2+ permeability of the Ca2+ store membrane is increased by InsP3. InsP3 did not cause an increase in the Ca2+ permeability of phospholipid vesicles (liposomes), indicating that this agent may bring about Ca2+ release by a specific effect on the physiologically relevant Ca2+ channels or carriers in the non-mitochondria) Ca2+ store site. The passive Ca2+ release by InsP3 was enhanced by ATP and an unhydrolyzable ATP analogue, 5'-adenylyimidodiphosphate, but not by ADP or AMP. The passive Ca2+ release by InsP3 was observed even at 0°C.View full abstractDownload PDF (610K) -
Takanori KAWAMURA, Wakako HIGUCHI, Yumiko EMOTO, Katsuhisa TAWADA1985 Volume 97 Issue 6 Pages 1583-1593
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSWe have examined whether heavy meromyosin (HMM) consists of a single kind of active site by analyzing the changes in the relative MgATPase activity and the relative amplitude of the ATP-induced fluorescence enhancement of the protein when the fraction of HMM “affinity”-labeled by vanadate plus ADP was varied. The analysis is based on a prediction that these two changes should be proportional to each other if myosin consists of a single kind of active site and generates the rate-limiting myosin**product complex emitting enhanced fluorescence. Although the difference between these two changes was very small with native HMM, it was large with HMM in which 5 fast-reactive sulfhydryl-groups per head were pre-modified with thimerosal. The difference indicated the existence of heterogeneous active sites in the SH-modified HMM. The results were best explained in terms of the hypothesis that fifty percent of the active site splits MgATP by a mechanism giving a fluorescence enhancement whereas the other fifty percent splits MgATP by another mechanism giving no fluorescence enhancement. Two possible explanations for the existence of heterogeneous active sites in the SH-modified HMM are discussed. One assumes the pre-existence of some sort of 1:1 heterogeneity in the microenvironment of the active sites and the other, which is considered less likely, assumes the introduction of the heterogeneity as a result of the SH-modification.View full abstractDownload PDF (982K) -
Koei HAMANA, Shigeru MATSUZAKI1985 Volume 97 Issue 6 Pages 1595-1601
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPolyamine contents of various species of plants and fungi including Bryophyta, Pteridophyta, Gymnospermae, Ascomycota, Basidiomycota, and Lichenobionta were determined by the combination of six chromatographic techniques. Polyamines examined included putrescine, spermidine, spermine, 1, 3-diaminopropane (diaminopropane), sym-norspermidine (norspermidine), sym-norspermine (norspermine), thermospermine, caldopentamine, homocaldopentamine, cadaverine, aminopropylcadaverine, sym-homospermidine (homospermidine), agmatine, and canavalmine. In addition to the widely occurring polyamines (putrescine, spermidine, and spermine), the “unusual” polyamines norspermidine and norspermine were found to be widely distributed in Bryophyta and Lichenobionta. These two polyamines were not detected in any species of Pteridophyta, Gymnospermae, and fungi even though their possible precursor, diaminopropane, was found in some species. Homospermidine was one of the major polyamines in Bryophyta and Lichenobionta, and was detected in most species of Pteridophyta and sporadically in higher plants. Agmatine was detected in most species of Bryophyta and in certain species of Gymnospermae. These data suggest that norspermidine, norspermine, and homospermidine can serve as chemical phylogenic and taxonomic markers in Plantae and Fungi.View full abstractDownload PDF (539K) -
Shin NAKAMURA, Shunji GOTOH, Osamu TAKENAKA, Kenji TAKAHASHI1985 Volume 97 Issue 6 Pages 1603-1609
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSMonkey (Macaca fuscata) mononuclear leukocytes were stimulated to produce thromboplastin (tissue factor) upon exposure to lipopolysaccharide, LPS. The stimulation was dose-related in the concentration range of 10-5 to 10-1 μg/ml of LPS. Lipid A portion of the LPS molecule was essential to induce the leukocyte ability for tissue factor generation. Thus, a lipid-lipid interaction between LPS and the cells is a plausible trigger for eliciting the ability. Approximately 50%. of the tissue factor thus produced appeared to be located on the cell surface, at which the coagulation cascade is probably initiated via the activation of factor VII. Among monkey mononuclear cell populations, monocytes were responsible for LPS-induced tissue factor production. Lymphocytes amplified the basal ability of monocytes to produce the factor by two-fold at physiological lymphocyte-monocyte ratios of 8:1 to 10:1. This indicates a complementary effect of lymphocytes upon the LPS-mediated monocyte ability. The medium supernatant from LPS-stimulated lymphocytes affected the monocyte competence while the stimulated lymphocytes did not. This result suggests that a soluble product of lymphocytes, i.e., lymphokinelike mediator, but not the cellular entity, participates in LPS-induced tissue factor production of monocytes.View full abstractDownload PDF (616K) -
Takashi MORITA, Sadami OHTSUBO, Takanori NAKAMURA, Shigenori TANAKA, S ...1985 Volume 97 Issue 6 Pages 1611-1620
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSExposure of limulus hemocytes to bacterial endotoxins (lipopolysaccharide, LPS) results in the activation of the intracellular clotting system, consisting of several protein components. During the separation of these components, a potent anticoagulant, named anti-LPS factor, which inhibits the endotoxin-mediated activation of the coagulation cascade, was found in hemocytes from both Tachypleus tridentatus and Limulus polvphemus (Tanaka, S., et al. (1982) Biochem. Biophys. Res. Commun. 105, 717-723). The principle isolated from the Tachypleus hemocyte lysate by column chromatographies on dextran sulfate-Sepharose CL-6B and Sephadex G-50 under sterile conditions was a simple basic protein with an apparent molecular weight of 15, 000. It consisted of a single chain polypeptide containing a total of 128 amino acids. The COOH-terminal end was presumed to be histidine, but no NH2-terminal end reactive to phenylisothiocyanate was detected. The isolated anti-LPS factor specifically inhibited the endotoxin-mediated activation of factor C, which has recently been identified as an LPS-sensitive serine protease zymogen in the hemocytes. This inhibition appeared to be due to the binding of anti-LPS factor with LPS. Moreover, anti-LPS factor had an antibacterial effect on the growth of Gram-negative bacteria (Salmonella minnesota R595 and 1114W) but not on that of Gram-positive bacteria (Staphylococcus aureus 209P). These biological activities of the isolated anti-LPS factor suggest an important role in cellular defence of limulus against microbial invasion.View full abstractDownload PDF (1483K) -
Hideyoshi YOKOSAWA, Rie ODAJIMA, Shin-ichi ISHII1985 Volume 97 Issue 6 Pages 1621-1630
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA purified preparation of trypsin inhibitor was obtained from the hemolymph of a solitary ascidian, Halocynthia roretzi, by a procedure including trypsin-Sepharose chromatography, DEAE-cellulose chromatography, and Sephadex G-50 gel filtration. The product was a mixture of two isoinhibitors, inhibitors I and II. They were separated from each other by high-performance liquid chromatography on an anion exchanger column, and showed almost identical amino acid compositions. They were also indistinguishable in terms of apparent specific inhibitory activity against bovine trypsin when the activity was assayed with the inhibitors at rather high concentrations (> 50 nM). A large difference was observed between them, however, in the inhibition constants, which correspond to the dissociation constants of the inhibitor-trypsin complexes; the inhibition constant of inhibitor I was 90 pM, whereas that of inhibitor II was 4.7 nM. The molecular weights of inhibitors I and II were estimated to be 6, 000 and 4, 500, respectively, by SDS-polyacrylamide gel electrophoresis, while an almost identical value, 9, 000, was obtained for both of them by gel filtration. The molecular weight calculated from the amino acid compositions was 5, 929 for both. The isoelectric points were also identical, that is about 5.0. Both of the inhibitors were heat-stable. Ascidian inhibitor I also inhibited other trypsin-like enzymes of mammalian origin, as well as those of ascidian origin.View full abstractDownload PDF (1467K) -
Mineo TAKEI, Ken-ichi GOTOH, Takafumi WATANABE, Tetsuya SUGA1985 Volume 97 Issue 6 Pages 1631-1636
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe effect of the chain length of fatty acids on peroxisomal enzyme activities of Tetrahymena pyriformis was investigated. The growth of cells and the activities of peroxisomal enzymes were inhibited markedly by the addition of medium-chain fatty acids (C6-C12) to the culture medium, whereas the addition of longer-chain fatty acids (C14-C18) resulted in a slight increase of growth and in the marked stimulation of enzyme activities concerned with fatty acid β-oxidation and the glyoxylate cycle in peroxisomes. Peroxisomal β-oxidation (fatty acyl-CoA oxidase) was more potent towards longer-chain fatty acids than the mitochondrial activity (fatty acyl-CoA dehydrogenase). The induction of the peroxisomal β-oxidation system by palmitate was repressed both by the addition of glucose and the aeration of the culture medium, whereas that of the peroxisomal glyoxylate cycle was repressed only by the addition of glucose to the medium.
These results indicate that peroxisomal enzyme systems related to the β-oxidation of fatty acids and the glyoxylate cycle are regulated by the compositions of fatty acids, glucose, and oxygen in the medium.View full abstractDownload PDF (484K) -
Toshio SHIMADA, Hisao KATO, Hiroshi MAEDA, Sadaaki IWANAGA1985 Volume 97 Issue 6 Pages 1637-1644
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe interaction of high-molecular-weight (HMW) kininogen, Factor XII and prekallikrein with sulfatide was studied by fluorescence polarization. Fluorescein-conjugated derivatives of HMW kininogen, Factor XII and prekallikrein were prepared by reacting the purified bovine factors with fluorescein isothiocyanate (FITC). The apparent dissociation constant (Kd) for the binding of FITC-labeled HMW kininogen (F-HMW kininogen) with sulfatide was calculated to be 3.2 (±0.3)×10-8M. This binding was partially inhibited by three kininogen derivatives, fragment 1.2, kinin-free protein and fragment 1•2-light chain, but not by kinin and fragment 1•2-free protein. In the presence of Factor XII, the binding of FHMW kininogen with sulfatide was strongly inhibited, suggesting that the zymogen and the protein cofactor compete for the same or a closely related binding site on the sulfatide surface. In contrast, the binding of FITC-labeled Factor XII (F-Factor XII) with sulfatide was weakly inhibited by HMW kininogen but not by prekallikrein. The Kd value for binding of F-Factor XII with sulfatide was calcu-lated to be 2.0 (±0.3)×10-8M.
F-Prekallikrein did not interact with sulfatide. Moreover, the fluorescence polarization value of F-HMW kininogen decreased in the presence of prekallikrein, leveling off at a one-to-one molar ratio of prekallikrein to F-HMW kininogen. The Kd value for binding of F-HMW kininogen-light chain (F-light chain) with prekal-likrein was calculated to be 3.8 (±0.6)×10-8M and the stoichiometry was estimated as 1 to 1.2 on a molar basis from the Scatchard plot. These results indicate that HMW kininogen and Factor XII interact directly with sulfatide, but prekallikrein binds to sulfatide indirectly in the form of complex with HMW kininogen.View full abstractDownload PDF (624K) -
Kunihiko KONNO, Shizuo WATANABE1985 Volume 97 Issue 6 Pages 1645-1651
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSChymotryptic digestability of scallop myosin was studied by measuring (a) changes in the gel electrophoretic pattern and (b) production of the soluble fraction obtained by centrifugation. Chymotryptic digestion of essential light chain (SH-LC) was strongly inhibited by association of regulatory light chain (R-LC) with myosin. This is in agreement with the observation of Stafford et al. (Biochemistry 18, 5273 (1979)). SH-LC and R-LC were both more resistant to the chymotryptic digestion when R-LCs were associated with myosin in the presence of calcium than when they dissociated from myosin in the presence of EDTA. In contrast, heavy chains of scallop myosin were digested more quickly in the presence of calcium than EDTA. This suggests that association of R-LC induces reversible changes in the heavy chain conformation, which lead to an increase in the chymotryptic digestability of heavy chains. The chymotryptic digestability of scallop myosin increased in two distinct phases as the calcium concentration in the digestion medium was increased, but monophasically as the magnesium concentration was increased. The magnesium increased the digestability by approximately half as much as did calcium. These findings suggest two types of attachment between regulatory light chains and desensitized myosin: one mediated specifically by low concentrations of calcium ions, the second by higher concentrations of either calcium or magnesium.View full abstractDownload PDF (2594K) -
Koei HAMANA, Masahiro KAMEKURA, Hiroshi ONISHI, Takashi AKAZAWA, Shige ...1985 Volume 97 Issue 6 Pages 1653-1658
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSQualitative and quantitative determinations of polyamines have been done in 4 photosynthetic eubacteria and 6 extreme-halophilic archaebacteria. For comparison, 5 moderate-halophilic eubacteria were also analyzed to determine their polyamine contents. Not only putrescine and spermidine but also homospermidine were found in the photosynthetic eubacteria, especially in the N2-fixing species, Rhodospirillum and Chromatium. Norspermidine, norspermine, and spermine were not detected in the phototrophic eubacteria. No appreciable amount of any polyamine was found in extreme-halophilic archaebacteria, Halobacterium and Halococcus, while moderatehalophilic eubacteria contained quite high concentrations of putrescine and spermidine and cadaverine. When arginine was incubated with cell lysates of these two archaebacteria, appreciable amounts of agmatine were produced; neither putrescine nor cadaverine was formed in the presence of ornithine or lysine. No detectable amount of spermidine was produced by the lysates on incubation with putrescine.View full abstractDownload PDF (506K) -
Kiyoshi ABE, Sadao KIMURA, Reiko KIZAWA, F. Koichi ANAN, Yoshiki SUGIT ...1985 Volume 97 Issue 6 Pages 1659-1668
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe amino acid sequences of human, porcine, and bovine erythrocyte cytochromes b5 which are soluble and present in the cytosol have been determined. In addition, the partial sequences of microsome-bound liver cytochrome b5, namely the sequence of the N-terminal region and joint region between the heme-containing and membranous part, have been established for human and porcine sources. All the cytochromes b5 from erythrocyte and liver contained N-acetylated N-termini. Of the 97 amino acid residues of erythrocyte cytochrome b5, residues 1-96 were identical with those of the liver protein of the same species. However, residue 97 (C-terminal residue) was proline for human erythrocyte cytochrome b5 and serine for the porcine protein, while residues 97 (joint region) of human and porcine liver cytochromes b5 were threonine. These findings indicate that the two forms of cytochrome b5 are encoded by two different but closely related mRNAs.View full abstractDownload PDF (760K) -
Masato NAGAOKA, Kei-ichi KAMISANGO, Hideji FUJII, Kei-ichi UCHIKAWA, I ...1985 Volume 97 Issue 6 Pages 1669-1678
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe structure of polysaccharide prepared by lysozyme digestion from the cell wall of Propiozzibacterium acnes strain C7 was examined. The polysaccharide fraction was composed of glucose, galactose, mannose, galactosamine, and diaminomannuronic acid in a molar ratio of 1:1:0.3:1:2. By Smith degradation of the polysaccharide, diaminouronic acid-containing fractions were obtained, and the configuration of diaminouronic acid was identified as 2, 3-diacetamido-2, 3-dideox-ymannuronic acid [Man(NAc)2A] by means of 1H-NMR and 13C-NMR spectroscopic analyses. The results of analyses involving methylation and partial acid hydrolysis led to the conclusion that the polysaccharide has the repeating unit→6) Gal (αl→4) Man(NAc)2A (β1→6) Glc (α1→4) Man(NAc)2A (β1→3) GalNAc (β1-. In addition, a portion of the galactose residues were substituted at C-4 by α1→2 linked mannotriose.View full abstractDownload PDF (791K) -
Kuniji TANAKA, Takashi KARIGANE, Sachie FUJII, Takuma CHINZAKA, Shinic ...1985 Volume 97 Issue 6 Pages 1679-1688
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA purified levan fructotransferase preparation from the culture of the bacterium Arthrobacter ureafaciens, which produces di-D-fructose 2, 6':6, 2' dianhydride (difructose anhydride IV) from levan by an intramolecular levan fructosyl transfer (ILFT) reaction, was found to produce a trioligofructan and a tetraoligofructan from levan in the presence of levanbiose, indicating the intermolecular fructosyl and levanbiosyl transfer (LFT and LBT) reactions. The tri- and tetraoligofructans were identified to be levantriose and -tetraose respectively. Increase in the levanbiose concentration brought about increased production of both oligofructans with decreased formation of difructose anhydride IV, supporting the previous theory proposed by Tanaka et al. (1983) that the ILFT, LFT, and LBT reactions are catalyzed by the same enzyme. In addition, there existed a roughly stoichiometric relationship between the increase and decrease in the productions of these oligofructans, and the LBT reaction was found to occur more intensively than the LIFT reaction. Acceptor specificity of the LFT and LBT reactions was studied using fifteen sugars including mono-, di-, and trisaccharides. The enzyme showed both of the reactions only with levanbiose, -triose, and kestose, indicating that the exposed non-reducing levanbiosyl residue was essential for the acceptor and suggesting the existence of a levanbiosyl acceptor site on the enzyme molecule.View full abstractDownload PDF (2790K) -
Yuki ITO, Nobuko SENO, Isamu MATSUMOTO1985 Volume 97 Issue 6 Pages 1689-1694
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSNew procedures to immobilize high concentrations of protein ligands by reductive amination on two types of formyl-carriers (I & II) having different spacer lengths were investigated in order to prepare stable and high-capacity adsorbents essential for efficient affinity chromatography. Formyl-carrier (I) was prepared by reductive amination with glutaraldehyde of the amino-carrier obtained on amination of an epoxy-activated carrier. Formyl-carrier (Il) was prepared by sodium metaperiodate (NaIO4) treatment of a glyceryl-carrier obtained on hydrolysis of an epoxy-activated carrier. Especially high concentrations of protein ligands were immobilized on formyl-Sepharose 4 B (I) under very mild conditions (pH 7.0, 4°C). A series of lectins, one of the most useful classes of group-specific ligands, was successfully immobilized by the procedures. Concanavalin A-Sepharose 4 B (I) thus obtained exhibited an adsorption capacitiy five times greater than that of concanavalin A-Sepharose 4 B made by Pharmacia Fine Chemicals, and could be repeatedly used over twenty times without a significant reduction in its adsorption capacity.View full abstractDownload PDF (502K) -
II. Shape Change of the MoleculeKikuko TAKEUCHI, Kazunori ISHIMURA1985 Volume 97 Issue 6 Pages 1695-1708
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPorcine platelet myosin molecules were examined by electron microscopy for changes in their shape. At high ionic strength, the molecules were morphologically indistinguishable from skeletal muscle myosin, except for a slight difference in the bent regions of their tails. At physiological ionic strength, however, the following important difference was observed between the two myosins. Unlike skeletal muscle myosin, the filaments of nonphosphorylated platelet myosin could be disassembled by stoichiometric ATP into a monomeric form with sharply bent or folded tail, and reassembled after ATP hydrolysis. Similar disassembly changes could be induced by various nucleotide triphosphates (CTP, GTP, ITP, and UTP) and to a lesser extent by ADP, AMP, and AMPPNP.
These results suggest that ATP binds to the hydrolytic sites in platelet myosin molecule and induces the molecular shape change.View full abstractDownload PDF (9225K) -
Hidehiko NAKAGAWA, Tomio KOTANI, Sachiya OHTAKI, Jun-ichi KAWANO, Eizo ...1985 Volume 97 Issue 6 Pages 1709-1718
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA monoclonal antibody (30. 1. 2) to hog thyroid peroxidase was produced, purified, and characterized. The IgG of 30. 1. 2 formed an immune complex with the peroxidase in a 1:2 or 1:1 molar ratio depending on the IgG to antigen ratio in the incubation mixture. Immune complex formation did not inhibit the peroxidase activity, which was actually activated 2-fold in the 1:1 complex. Studies of the binding of the conjugate of the IgG or its Fab' with horseradish peroxidase to untreated and acetone-treated thyroid microsomes showed that the IgG conjugate could bind to only a very small portion of the total binding sites (thyroid peroxidase) present in untreated microsomes even after prolonged incubation. The binding of the Fab' conjugate to untreated microsomes, on the other hand, increased ass the incubation time was increased, reaching 40% of the total sites after 20h of incubation. These findings indicated that thyroid peroxidase is localized on the inner surface of the microsomal membranes and that the Fab' conjugate, but not the IgG conjugate, can slowly penetrate through the membrane barrier to reach the peroxidase. Immunohistochemical experiments using the Fab' conjugate as a probe revealed that most thyroid peroxidase in the thyroid gland is located in the endoplasmic reticulum and perinuclear cisternae of the follicular cell, although a small amount could occasionally be detected in the apical membrane including microvilli. In contrast to previous reports, no thyroid peroxidase could be found in other cellular structures such as Golgi apparatus and apical vesicles by the immunohistochemical technique employed.View full abstractDownload PDF (4009K) -
Kyoko SHIBUYA, Shigeru NOGUCHI, Mineo YAMAKI, Susumu NISHIMURA, Takao ...1985 Volume 97 Issue 6 Pages 1719-1725
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSIn the rat, DNA carrying a cluster of the genes for tRNAAsp, tRNAGIY, and tRNAGlu, aligned in that order, is repeated about 10 times. Seven DNA clones corresponding to the independent repeating units were isolated from a rat gene library. Nucleotide sequence analysis of these clones revealed the presence of a fourth tRNA gene, the gene for tRNALeu in the cluster. The tRNALeu gene is located about 600 base pairs (bp) upstream from the tRNAAsp gene and its polarity differs from those of the other three tRNA genes. Among the repeating units, the nucleotide sequence of tRNALeu is conserved to a relatively high degree.View full abstractDownload PDF (1338K) -
Masako WAGATSUMA, Masuo OBINATA, Yasuoki MOROI, Fumio HANAOKA, Masa-at ...1985 Volume 97 Issue 6 Pages 1727-1735
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSHeterogeneous nuclear RNA-ribonucleoprotein (hnRNP) fractions were isolated from Friend erythroleukemia cells and separated by 15-45% sucrose gradient centrifugation. The distribution of small nuclear RNAs (snRNAs) in hnRNP fractions indicated that the snRNAs are associated with hnRNP particles. HnRNP fractions were incubated with normal IgG or anti-U1 RNP IgG, and the resulting immunocomplexes were isolated by binding to a protein A-Sepharose column. HnRNP was found in bound fractions only when anti-U1 RNP IgG was used. By Northern hybridization of RNA extracted from the immunocomplexes with a β-globin genomic DNA probe, 15 S β-globin mRNA precursors and 10 S mature mRNA were detected. These findings suggest the existence of a complex of U1 RNP particles and hnRNP particles containing β-globin pre-mRNA.View full abstractDownload PDF (3045K) -
Activation of Guinea Pig Peritoneal Macrophages by Platelet Activating Factor (PAF) and Its AgonistsHidetoshi HAYASHI, Ichiro KUDO, Keizo INOUE, Kikuo ONOZAKI, Susumu TSU ...1985 Volume 97 Issue 6 Pages 1737-1745
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe platelet activating factor (PAF: 1-O-alkyl-2-O-acetyl-sn-glycero-3-phospho-choline) and its analogs were examined to determine their effects on guinea pig peritoneal macrophages.
1. PAF activated macrophages, but its effect on macrophages was much weaker than that observed on platelets: the concentration required for 50% maximum activation was 8.5×10-6M for macrophages and 2.9×10-10M for platelets.
2. Three PAF agonists, 1-O-octadecyl-2-O-(N, N-dimethylcarbamoyl)-glycero-3-phosphocholine (Compound I), 1-O-octadecyl-2-acetamido-2-deoxy-glycero-3-phosphocholine (Compound II), and 1-O-octadecyl-2-O-methyl-glycero-3-phosphocholine (Compound III), showed higher activity in stimulating macrophage function than PAF. The abilities of these non-metabolizable PAF agonists to activate macrophage paralleled their relative potency to induce platelet activation.
3. The sn-3 enantiomers of PAF and Compound III exhibited activity, while the sn-1 did not. By comparing the activities of derivatives of Compound III, it was shown that the long-chain alkyl-ether group in the glycerol-1 position, a relatively small size of the substituent on the hydroxy group at the sn-2 position, and the choline moiety in the glycerol-3 position must play critical roles in the process of macrophage activation.
4. A specific PAF antagonist, CV3988, which inhibits PAF-induced platelet activation and hypotension, inhibited the activation of macrophages caused by PAF and its agonists.
5. Radioactive PAF and Compound III were synthesized and incubated with macrophages. More than 99% of PAF was converted to lysoPAF and 1-alkyl-2-acyl-glycerophosphocholine during a 72h incubation. On the other hand, 60% of Compound III remained intact. The rapid degradation of PAF may explain why the effect of PAF on macrophages was relatively weak.
These results indicate that PAF and PAF agonists cause macrophage activation through specific binding to a macrophage cell surface receptor, which recognizes the structure and configuration of PAF. Our findings support the concept that PAF is a potent mediator in some pathological process.View full abstractDownload PDF (687K) -
Tadashi YOSHIMOTO, Katsuhiko YAMAMOTO, Daisuke TSURU1985 Volume 97 Issue 6 Pages 1747-1754
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA strain of Streptomyces isolated from soil was found to produce a large amount of tyrosinase (monophenol, dihydroxy-L-phenylalanine: oxygen oxidoreductase: EC 1. 14. 18. 1) extracellularly. The enzyme was purified from the culture filtrate about 550-fold by a series of column chromatographies on Duolite A-2 and CM-cellulose and gel filtration on Sephadex G-100. The purified enzyme appeared homogeneous as judged by disc gel electrophoresis. The enzyme catalyzed the hydroxylation of monophenols and the oxidation of diphenols and was most active at pH 6.8 with dihydroxy-L-phenylalanine (L-DOPA) as the substrate. It was inhibited by kojic acid, diethyldithiocarbamate, and inhibitors obtained from microorganisms. The isoelectric point of the enzyme was 9.9, and the molecular weight was estimated to be 36, 000 by gel filtration on Sephadex G-100 and 29, 000 by sodium dodecyl sulfate (SDS) gel electrophoresis, which suggests that the enzyme is a monomer. Metal analysis by atomic absorption spectroscopy indicated that the enzyme contains nearly 1 gram atom of copper per mol.View full abstractDownload PDF (1119K) -
Kiyoshi NAGATA, Porntip BUPPODOM, Tamihide MATSUNAGA, Makoto ISHIMATSU ...1985 Volume 97 Issue 6 Pages 1755-1766
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA total of nine forms of cytochrome P-450 were purified to homogeneity from liver microsomes of male Wistar rats. They were P-451 I and P-451 II from untreated rats, P-450 II and P-450 III from phenobarbital-treated rats, MC-P-448 L and MC-P-448 H from 3-methylcholanthrene-treated rats, and P-452, P-448 L, and P-448 H from 3, 4, 5, 3', 4'-pentachlorobiphenyl-treated rats. Among them, MC-P-448 L and MC-P-448 H were indistinguishable from P-448 L and P-448 H, respectively, with regard to electrophoretic, spectral, catalytic and immunochemical properties, and thus seven forms were distinct hemoproteins. The minimal molecular weight of each form was as follows: P-451 I (49, 000), P-451 II (52, 000), P-450 II (52, 000), P-450 III (53, 500), P-452 (48, 000), P-448 L (56, 000), P-448 H (54, 000). Judging from the oxidized absolute spectra, P-448 H was a high-spin form and the others were of low-spin type.
In a reconstituted system, N-demethylations of benzphetamine and aminopyrine were catalyzed by most of the forms at comparable rates. On the other hand, the activities for the oxidations of benzo[a]pyrene, 7-ethoxycoumarin, biphenyl, and estradiol-17β varied greatly among the forms of cytochrome P-450. The most efficient catalysts were as follows: P-448 L and P-451 II for benzo[a]pyrene 3-hydrox-ylation; P-448 L for 7-ethoxycoumarin O-deethylation; P-448 L, P-451 II, and P-448 H for biphenyl 4-hydroxylation; P-448 L and P-448 H for biphenyl 2-hydroxylation; and P-451 II and P-448 H for estradiol 2-hydroxylation. P-451 I, P-450 II, and P-450 III were somewhat poorer catalysts in metabolizing all the substrates except for benzphetamine and aminopyrine, but their substrate specificities were still distinguishable from one another. Of all the purified cytochrome P-450's, P-452 showed the least ability to metabolize all the substrates. Judging from the properties, it appears that six forms in male Wistar rats correspond to the distinct forms of cytochrome P-450 in Long-Evans and/or Sprague-Dawley rats reported by other workers, but P-451 I is a new constitutive isozyme in Wistar rats.View full abstractDownload PDF (1750K) -
Victor M. DARLEY-USMAR, Masahiko WATANABE1985 Volume 97 Issue 6 Pages 1767-1775
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSUsing the small amounts of muscle available from biopsy (_??_100mg), from both normal controls and a patient with a previously identified defect of the mitochondria) electron transfer protein complex III, we analyzed both structural and mitochondrial proteins. The myosin light chains were found to be unchanged with respect to charge or size between patient and control. Two prominent proteins detected after two dimensional gel electrophoresis were present in the patient's total homogenised muscle protein but were not detected in the controls. One protein was positively identified as cytochrome c oxidase subunit II and the other tentatively as a component of the ATP synthetase. We suggest that the increased amounts of these proteins represents a response of the patients muscle cells to the ATP deficiency caused by the primary lesion in complex III.View full abstractDownload PDF (4100K) -
Sadaki FUJIMOTO, Kazuki MURAKAMI, Akira OHARA1985 Volume 97 Issue 6 Pages 1777-1784
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSChemical modification studies of manganese(III)-containing acid phosphatase [EC 3. 1. 3. 2] were carried out to investigate the contributions of specific amino-acid side-chains to the catalytic activity. Incubation of the enzyme with N-ethylmaleimide at pH 7.0 caused a significant loss of the enzyme activity. The inactivation followed pseudo-first-order kinetics. Double log plots of pseudo-first-order rate constant vs. concentration gave a straight line with a slope of 1.02, suggesting that the reaction of one molecule of reagent per active site is associated with activity loss. The enzyme was protected from inactivation by the presence of molybdate or phosphate ions. Amino acid analyses of the N-ethylmaleimide-modified enzyme showed that the 96%-inactivated enzyme had lost about one histidine and one-half lysine residue per enzyme subunit without any significant decrease in other amino acids, and also demonstrated that loss of catalytic activity occurred in parallel with the loss of histidine residue rather than that of lysine residue. Molybdate ions also protected the enzyme against modification of the histidine residue. The enzyme was inactivated by photooxidation mediated by methylene blue according to pseudo-first-order kinetics. The pH profile of the inactivation rates of the enzyme showed that an amino acid residue having a pKa value of approximately 7.2 was involved in the inactivation. These studies indicate that at least one histidine residue per enzyme subunit participates in the catalytic function of Mn(III)-acid phosphatase.View full abstractDownload PDF (591K) -
Hirofumi UENO, Tsuyoshi KATOH, Fumi MORITA1985 Volume 97 Issue 6 Pages 1785-1793
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe alkali light chain of rabbit skeletal muscle myosin, A1, was cyanylated with 2-nitro-5-thiocyanobenzoic acid, and the peptide bond at Cys 177 was subsequently cleaved in the presence of 0.05M CaC12. Two peptide fragments, from the N-terminal to the residue 176 (CF1) and from the residue 177 to the C-terminal (CF2), were obtained. The CD spectrum and the difference UV absorption spectrum induced by CaCl2 suggested that CF1 largely retained the higher order structure of A1. The CF1 fragment, however, could neither incorporate subfragment-1 (S-1) by an exchange reaction, nor bind with the renatured 20K fragment of S-1 heavy chain. On the other hand, the C-terminal fragment of 14 residues, CF2, could bind with the 20K fragment of S-1 heavy chain. These results indicate that the binding site of the alkali light chain for the heavy chain of myosin is located within the C-terminal 14 residues.View full abstractDownload PDF (1596K) -
Kazuko MAEDA-YORITA, Kenji AKI1985 Volume 97 Issue 6 Pages 1795-1801
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSCovalent modification of glutathione reductase (GR) from yeast with 1-fluoro-2, 4-dinitrobenzene (FDNB) inhibited the NADPH-GSSG reductase activity completely. This modification also decreased the NADPH-thio-NADP+ transhydrogenase activity, stimulated the NADPH-oxidase activity, and induced the NADPH-cytochrome c reductase activity. Spectrophotometric titration showed that one tyrosine residue per FAD was modified with a dinitrophenyl group. The modified enzyme showed conversion of the two-electron reduced form (EH2) to the four-electron reduced form (EH4) in anaerobic conditions and conversion of EH2 to the oxidized form (E) in aerobic conditions.
These results indicate that the modification of one tyrosine residue of the active site induces the instability of EH2.View full abstractDownload PDF (520K) -
Makoto KINOSHITA, Tamio TERAMOTO, Hirokazu KATO, Yoshiaki HASHIMOTO, C ...1985 Volume 97 Issue 6 Pages 1803-1806
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe liver has two distinct lipoprotein receptors; one is the apolipoprotein (apo) B, E receptor and the other the apo-E receptor. In this study, the protein to which apo-E HDLc (cholesterol-induced high density lipoprotein containing apo-E as the predominant protein species) bound specifically was partially purified from the rat liver membrane by ion exchange chromatography and preparative gel electrophoresis. The molecular weight of the protein was estimated to be about 36K daltons and the protein bound to 125I-apo-E HDLc in a specific and saturable manner, suggesting that the protein is the apo-E receptor.View full abstractDownload PDF (1261K) -
Setsuo SAITO, Setsuo SAITO, Tomofusa TSUCHIYA1985 Volume 97 Issue 6 Pages 1807-1810
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA new nonionic detergent, heptylthioglucoside, was synthesized and found to be more soluble than octylthioglucoside in water at low temperatures. Use of this detergent for solubilization and reconstitution of membrane proteins of Escherichia coli was examined. Heptylthioglucoside was as effective as octylthioglucoside and octylglucoside in solubilizing membrane proteins, and by the heptylthioglucoside-dilution procedure the H+-translocating ATPase (F1F0) and melibiose carrier could easily be reconstituted into liposomes. It is concluded that heptylthioglucoside is very useful in studies on membrane proteins.View full abstractDownload PDF (270K) -
Tatsuya SUEYOSHI, Toshiyuki MIYATA, Sadaaki IWANAGA, Toshimasa TOYO'OK ...1985 Volume 97 Issue 6 Pages 1811-1813
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA simple, sensitive and reliable method for the detection of cystine-containing peptides has been developed. A peptide bridged with a disulfide bond was reduced and cleaved with tributylphosphine, and then coupled with a thiol specific reagent, ammonium 7-fluorobenzo-2-oxa-1, 3-diazole-4-sulfonate, under alkaline conditions. After incubation at 60°C for 1h, the fluorescent derivative formed was measured with excitation at 385 nm and emission at 515 nm. The intensity of fluorescence labeled to the peptide was very stable and the peptide containing disulfide was quantitatively determined in the range of 100 pmol to 10 nmol, when oxidized glutathione was used as a standard. This method was very useful for specific detection of cystine-containing peptides in the column effluents on reverse phase high performance liquid chromatography.View full abstractDownload PDF (213K) -
Hiroshi KAWASAKI, Susumu ITOH, Hisataka KASAI, Yukio MITSUI, Yoichi II ...1985 Volume 97 Issue 6 Pages 1815-1818
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSCrystals suitable for X-ray structure analysis were obtained for CaM complexed with both calcium ions and a phenothiazine drug, trifluoperazine (TFP). The TFP/CaM binding ratio in crystals was experimentally determined to be nearly 1. An attempt at crystallizing calcium-free calmodulin (CaM) resulted in rigid but non-birefringent solids which exhibited no X-ray reflections.View full abstractDownload PDF (995K) -
Mihoko USAMI, Akira TAKAHASHI, Tomoko KADOTA, Ken KATODA1985 Volume 97 Issue 6 Pages 1819-1822
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSCoated vesicles isolated from bovine brain contained a protein kinase(s) which phosphorylated phosvitin and an endogenous protein with a molecular weight (Mr) of 48, 000. A clathrin light chain (Mr 33, 000), a constituent of the coat structure of the coated vesicles, was also phosphorylated when histone was added to the incubation medium. The clathrin light chain was phosphorylated with GTP as well as ATP as the phosphoryl donor. The phosphorylation reaction was inhibited by heparin. An additional 1.35 mol of PO4/mol was incorporated into the clathrin light chain which had contained approximately 1.5 mol of PO4/mol when the coated vesicles were incubated with ATP, Mg2+, and histone. Phosphoamino acid determination revealed the presence of 32P-phosphorylated threonine and serine in phosvitin, threonine in the endogenous protein (Mr 48, 000) and serine in the clathrin light chain (Mr 33, 000).View full abstractDownload PDF (1003K) -
Toshihiko TANAKA, Keiji YAMAZAKI, Kenji SOBUE1985 Volume 97 Issue 6 Pages 1823-1826
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSWith large amounts of gizzard Mr 135, 000 calmodulin-binding protein (myosin light chain kinase), the phosphate incorporation into myosin light chains was determined to be 2 mol/mol of myosin light chain. The actin-activated ATPase activity was dramatically enhanced when myosin light chains were phosphorylated by more than 1 mol of phosphate incorporated/mol of myosin light chain.View full abstractDownload PDF (1329K) -
Yasuhiro TAKEDA1985 Volume 97 Issue 6 Pages 1827-1830
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSX-ray studies on the complex of E. coli DNA with synthetic thermospermine in fibers were carried out. This complex showed the ordinary transition, except that it yielded a semicrystalline B-form at 66% r. h., suggesting good side-to-side interactions of the material due to some number of cross-bridges of tetramine. An idea of thymine methyl-neighbor base short contacts in A-form DNA is proposed to understand these structural changes of double helical DNA. On the assumption that the unstable A-conformation needs lateral interactions, the present X-ray results are well explained. This unstable factor is potentially of considerable biological interest in relation with DNA compaction.View full abstractDownload PDF (1010K) -
Keisaku KIMURA, Hiroo INOKUCHI, Hitoko NANAMI, Tatsuhiko YAGI1985 Volume 97 Issue 6 Pages 1831-1833
Published: 1985
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSMagnetization and magnetic susceptibility measurements revealed that the hydrogenase [EC 1. 12. 2. 1] from Desulfovibrio vulgaris Miyazaki F has an independent unpaired electron in its iron-sulfur cluster. The paramagnetic center of the Desulfovibrio hydrogenase is, therefore, different from that in the Chromatium hydrogenase which interacts with another paramagnetic center, probably nickel.View full abstractDownload PDF (219K)
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