巻号一覧
92 巻, 6 号
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Yasuo SUZUKI, Makoto MATSUMOTO1982 年 92 巻 6 号 p. 1683-1692
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe subcellular distribution of the phospholipase activities and metabolism of lysophosphatidylcholine in cultured human cell line (FL cells) during “fusion-from-within” induced by measles virus were studied.
During cell fusion, fairly high activities of phospholipase A1 and A2, the optimal pHs of which were acidic, appeared in the cytosol. These phospholipases were confirmed to be of lysosomal origin by the following facts: (1) the properties of these phospholipases were the same as those of lysosomal phospholipase A1 and A2; (2) a decrease in the total activity of phospholipases A1, A2 and acid phosphatase in the lysosomal fraction of the infected cells coincided with an increase in their activity in the cytosol. The release of lysosomal phospholipase A1 and A2 into the cytosol of the infected cells appeared to be related to the extent of cell fusion-from-within. Phospholipase A1 and A2 released to the cytosol hydrolyzed the cell membrane-bound phospholipids to form lysophospholipids.
1-[1-14C] Palmitoyl-GPC, incorporated into the cells from the culture medium, was rapidly converted into phosphatidylcholine, triacylglycerol and phosphatidylethanolamine in the cells during fusion-from-within, but the radioactive lysophosphatidylcholine and fatty acids were hardly detectable, indicating a rapid turnover of cellular lysophosphatidylcholine during cell fusion. The subcellular lysophospholipid acyl-hydrolase activities of the infected cells were higher than those of normal cells.
Possible relation between the membrane fusion induced by measles virus and the phospholipid metabolism in the infected cells were discussed.抄録全体を表示PDF形式でダウンロード (794K) -
Yasuki NONAKA, Toshihiro SUGIYAMA, Toshio YAMANO1982 年 92 巻 6 号 p. 1693-1701
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーAdrenodoxin reductase from bovine adrenocortex was inactivated by arginine specific reagents, p-hydroxyphenylglyoxal, phenylglyoxal, 2, 3-butanedione, and 1, 2-cyclohexanedione. Inactivation of the enzyme caused by p-hydroxyphenylglyoxal obeyed pseudo-first-order kinetics and resulted in complete elimination of NADPH-ferricyanide reductase activity. The rate of inactivation increased with pH from 6.5 to 9.5. Ten out of 30-33 arginyl residues of the enzyme were modified, but residues essential to its enzymatic activity were less than 5. NADP+ strongly protected against inactivation by p-hydroxyphenylglyoxal, whereas NAD+ could afford only partial, weak protection. Furthermore, 2'-AMP and 2', 5'-ADP afforded considerable protection but 5'-AMP did not. These data suggest that adrenodoxin reductase has essential arginyl residues which are crucial to the enzymatic activity as the recognition site for the negatively charged 2'-phosphate group of NADP+.抄録全体を表示PDF形式でダウンロード (696K) -
Kuniyasu KAWABE, Kazuhiko IMAIZUMI, Kiyohiro IMAI, Itiro TYUMA, Hisano ...1982 年 92 巻 6 号 p. 1703-1712
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーTo clarify the functional role of the 2- and 4-side chains of heme in myoglobin oxygenation, we synthesized several new hemins carrying nonnatural side chains at positions 2 and 4, reconstituted myoglobins with them, and investigated their optical, ionization, and oxygen-binding properties. The absorption maxima for most of the reconstituted myoglobins except those reconstituted with hemins having carbonyl groups, no matter whether they are oxy-, deoxy-, or carbon monoxy-form, shifted by at most 20 nm toward shorter wavelengths than protoheme-myoglobin. The absorption spectrum is more affected by resonance effects than by inductive effects of the peripheral side chains of heme. Differences in optical and oxygenation properties between isomeric myoglobins carrying hemes with different side chains at positions 2 and 4 indicate that the 2- and 4-side chains of heme are functionally nonequivalent, as previously shown by Sono and Asakura [(1975) J. Biol. Chem. 250, 5227-5232] for monoformyl-monovinylheme myoglobins. Modification of the 4-side chain exerts greater influence on the oxygen affinity than that of the 2-side chain. The extrapolation method proposed by Sono and Asakura to correct for the protein factor seems to be applicable only as a special case and does not apply to the isomeric myoglobins studied by us. There was not correlation between pKa of the met-form and the oxygen pressure at half saturation, implying that the electronic effect of the side chains is not decisive for the oxygen affinity of myoglobin. The bulkiness of the 2- and 4-side chains, on the other hand, appear to have a certain relation to the affinity but is not a dominant factor. In addition to these factors, specific stereochemical considerations are required to explain all the oxygenation data for the various reconstituted myoglobins. We have proposed a stereochemical mechanism based on the movement of the heme group upon ligation of native myoglobin.抄録全体を表示PDF形式でダウンロード (767K) -
Kuniyasu KAWABE, Kazuhiko IMAIZUMI, Zen-ichi YOSHIDA, Kiyohiro IMAI, I ...1982 年 92 巻 6 号 p. 1713-1722
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーTo clarify the functional role of the 2- and 4-side chains of heme in hemoglobin we prepared several hemins carrying nonnatural side chains at positions 2 and 4, reconstituted human adult hemoglobins with them, and investigated their optical and oxygen binding properties. The absorption maxima for all these reconstituted hemoglobins, no matter whether they are oxy-, deoxy-, or carbon monoxy-form, shifted toward shorter wavelengths than those for protoheme-hemoglobin. As in the case of myoglobin (Kawabe, K., et al. (1982) J. Biochem. 92, 1703-1712), the absorption spectrum is more significantly affected by resonance effects than by the inductive effects of the peripheral heme substituents. Contrary to the case of myoglobins, the spectral difference between pemptoheme-hemoglobin and isopemptoheme-hemoglobin and that between 2-isopropyl-4-vinyl-deuteroheme-hemoglobin and 2-vinyl-4-isopropyldeuteroheme-hemoglobin were very small. All the reconstituted hemoglobins used in this study showed higher oxygen affinity and reduced cooperativity in oxygen binding than native hemoglobin. We have shown that the 2- and 4-side chains are functionally nonequivalent and that modification of the 4-side chain exerts greater influence on oxygen affinity than modifying the 2-side chain. The magnitude of the Bohr effect and response to 2, 3-diphosphoglycerate and inositol hexaphosphate were reduced in the reconstituted hemoglobins. We have proposed a stereochemical mechanism based on constraint of heme movement before ligation against the tight distal side of the heme pocket.抄録全体を表示PDF形式でダウンロード (683K) -
Hiroaki SAWAI, Takahisa SHINOMIYA1982 年 92 巻 6 号 p. 1723-1730
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーAntibody to 2'-5' linked triadenylate, A 2' p 5' A 2' p 5' A, was prepared by injecting bovine serum albumin conjugated with A 2' p 5' A 2' p 5' A into rabbits. The [8-14C]-A 2' p 5' A 2' p 5' A used in the study was synthesized by nonenzymatic template-directed condensation of [8-14C] AMP and 5'-phosphorimidazolide of A 2' p 5' A on poly U. The specificity of the antibody was determined by the inhibition of the binding of the radioisotope probe to the antibody by a competitor using the ammonium sulfate precipitation method. The cross reactivity of a number of modified oligonucleotides has been evaluated in order to gain information on the structural feature involved in the binding to the antibody. The adenine moiety and 2'-5' internucleotide linkage are crucial regions for the binding. The antibody reacted not only on A 2' p 5' A 2' p 5' A and A 2' p 5' A 2' p 5' A 2' p 5' A, but also on a cordycepin analogue of the trimer, (3' dA) 2' p 5' (3' dA) 2' p 5' (3' dA), significantly. Considerable cross reaction was observed with oligoadenylates bearing both 2'-5' and 3'-5' internucleotide linkages, while there was little cross reaction with 3'-5' linked oligoadenylates. The antibody showed very low or no affinity for adenosine, adenine mononucleotides, other nucleotides and other 2'-5' linked trinucleotides. The cross reactivity of the modified oligonucleotides is indicated to have relation to the biological activity of the corresponding 5'-phosphorylated oligonucleotides, so far reported.
The antibody was further purified by affinity chromatography using RNA-Sepharose and AMP-Sepharose giving high specificity.抄録全体を表示PDF形式でダウンロード (614K) -
Tokuzo NISHINO, Nobuhiro SUZUKI, Hirohiko KATSUKI1982 年 92 巻 6 号 p. 1731-1740
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーEnzymatic formation of nerolidol was demonstrated by incubation of [14C] farnesyl pyrophosphate with the ultracentrifugal supernatant of cell-free extract of Rhodotorula glutinis. Farnesol was also formed concomitantly with the formation of nerolidol and the ratios of formation of both alcohols were from 1:3 to 1:4. Divalent cation was necessary for the reaction and Mn2+ was much more active than Mg2+ for nerolidol formation. No nerolidol was formed when farnesyl monophosphate or farnesol was used instead of farnesyl pyrophosphate as a substrate. Nerolidyl pyrophosphate or nerolidyl monophosphate could not be detected as an intermediate in the reaction. Based on these observations, nerolidol was presumed to be formed not via nerolidyl pyrophosphate or nerolidyl monophosphate but via a carbonium ion intermediate which was formed by cleavage of the carbon-oxygen bond of farnesyl pyrophosphate. This reaction seems to proceed in a similar manner to the acid hydrolysis of farnesyl pyrophosphate to form nerolidol and farnesol.抄録全体を表示PDF形式でダウンロード (789K) -
Hiromasa TOJO, Kihachiro HORIIKE, Kiyoshi SHIGA, Yasuzo NISHINA, Retsu ...1982 年 92 巻 6 号 p. 1741-1752
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThis paper describes the physical characterization of the monomeric unit of hog kidney D-amino acid oxidase apoenzyme in 6M guanidine hydrochloride (GuHCl) solution by means of differential refractometry, densimetry, light scattering, equilibrium sedimentation, and high-speed gel filtration chromatography. In 6M GuHCl solution, the oxidase interacts preferentially with GuHCl: the values of the preferential interaction parameter are 0.11±0.03 (S. D.)g/g of protein by densimetry and 0.14±0.04g/g of protein by refractometry. The volume change, ΔV, of the oxidase on transfer from the native to the denatured state is -350ml/mol. The molecular weight of the monomeric apoenzyme is 39, 600±1, 700 by light scattering and 38, 000±1, 200 by high-speed equilibrium sedimentation. The values of the molecular weight estimated by the empirical methods, i.e., sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and high-speed gel filtration chromatography in 6M GuHCl, agree well with those obtained by the thermodynamic methods mentioned above. These results confirm definitely that the complex of the apoenzyme with SDS normally behaves in the same manner as those of standard proteins in SDS-gel electrophoresis. This is also supported in this study by the analysis of the electrophoretic data at several gel concentrations by Ferguson plots. The molecular weight of quasi-D-amino acid oxidase apoenzyme was also examined by the empirical methods.抄録全体を表示PDF形式でダウンロード (999K) -
Akira HARA, Yoshihiro DEYASHIKI, Makoto NAKAGAWA, Toshihiro NAKAYAMA, ...1982 年 92 巻 6 号 p. 1753-1762
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーKidney has the greatest capacity among the tissues of chicken for reducing aromatic ketones, and two ketone reductases were separated from this tissue by DEAE-cellulose chromatography and isolated. Though both are monomeric proteins with a molecular weight of 29, 500, and with similar amino acid compositions and immunological properties, they differ in their pI values. The two enzyme species show no apparent difference in catalytic properties; aromatic ketones, aldehydes and quinones are reduced at high rates and alicyclic ketones such as 3-ketosteroids and prostaglandin E2 at low rates. The substrate affinity for several representative substrates at pH 7.2 is higher than that at the optimal pH of 6.3. Both enzymes prefer NADPH to NADH as a cofactor. Low NADP+-dependent reverse reactions occur with 9- and 15-hydroxyprostaglandins and certain alcohols as substrates. The enzymes show similar sensitivities to heavy metal ions, SH-reagents, quercitrin, indomethacin, and FMN.抄録全体を表示PDF形式でダウンロード (1302K) -
Koichiro TANAKA, Tomisaburo KAKUNO, Jinpei YAMASHITA, Takekazu HORIO1982 年 92 巻 6 号 p. 1763-1773
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリー1. Chlorophyllase [EC 3. 1. 1. 14] was extracted from the acetone-dried powder of the chloroplasts of greened rye seedlings with 1% cholate, and purified 870-fold with a yield of about 30%. The purification procedure was composed of fractionations with acetone and ammonium sulfate, and hydrophobic chromatography on a phenyl-Sepharose CL-4 B column.
2. The purified enzyme was pure as analyzed by molecular-sieve chromatography and isoelectric electrophoresis. It had an isoelectric point of 4.5 and a molecular weight of 39, 000.
3. The purified enzyme was stable at pH 6-9 and 4&C. At pH 7.5, it was stable in the presence and absence of 30% acetone. However, at 30&C, it was not stable above a 10% concentration of acetone.
4. The purified enzyme hydrolyzed chlorophylls a and b from spinach into chlorophyllides a and b and phytols, respectively; and bacteriochlorophyll a from Rhodospirillum rubrum into bacteriochlorophyllide a and a derivative of phytol, possibly all-trans-geranylgeraniol. The hydrolysis rates were stimulated to their maxima in the presence of 30% acetone; maximum stimulation was about 50% with bacteriochlorophyll a and about 400% with chlorophyll a.
5. At pH 7.5 and 30&C in the presence of 30% acetone, the Km values and specific activities were 12 μM and 480 nmol•min-1•mg-1 for chlorophylls a, and 4 μM and 170 nmol•min-1•mg-1 for R. rubrum bacteriochlorophyll a, respectively.抄録全体を表示PDF形式でダウンロード (1338K) -
Kazuhiro INOUE, Hiroshi KORENAGA, Shizuo KADOYA1982 年 92 巻 6 号 p. 1775-1784
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーA new sulfated polysaccharide was isolated from the culture supernatant of a strain of Arthrobacter sp. The polysaccharide purified with quaternary ammonium salts consists of D-galactose, D-glucose, sulfate, phosphorus, glucosamine, muramic acid, alanine, glutamic acid, glycine, and LL-diaminopimelic acid in a molar ratio of 56:9.0:68:6.4:2.0:1.1:2.1:1.0:1.2:1.2. The presence of the two amino sugars and four amino acids suggests that the polysaccharide, which is principally a galactan sulfate, contains small amounts of so-called peptidoglycan and that it is derived from the bacterial cell-wall polysaccharide. Gel filtration indicates the heterogeneity of the purified polysaccharide in its peptidoglycan content and molecular size. The molecular weight of its major portion was estimated to be 2.3±104 by gel filtration. The fractions GS-I and GS-II, and GS-4M and GS-5M, which were obtained by fractionation of the polysaccharide on Sephacryl S-200 and Dowex 1-X2 (Cl- form), respectively, gave almost the same chemical composition as the original polysaccharide, except in the peptidoglycan content, indicating that this polysaccharide is a series of complexes composed of essentially equal, sulfated polysaccharide chains and peptidoglycan fragments in their various ratios. The polysaccharide has MD - 36& and is composed predominantly of β-glycosidic linkages, as judged from its specific optical rotation (-37&) and the infrared absorption (885cm-1) of its desulfated material. It exhibits a potent antithrombin activity (ID50, 0.82 μg/ml). A possible partial structure of the polysaccharide is also discussed, based on the results of periodate oxidation, Smith degradation, and alkali treatment.抄録全体を表示PDF形式でダウンロード (857K) -
Toshihiro OHURA, Eiki KOMINAMI, Keiya TADA, Nobuhiko KATUNUMA1982 年 92 巻 6 号 p. 1785-1792
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーOrnithine aminotransferase [EC 2. 6. 1. 13] was purified and crystallized from human liver by a procedure involving heat treatment, chromatographies on DEAE-cellulose, Octyl-Sepharose CL-4 B and Sephadex G-200, and crystallization. The purified enzyme appeared to be homogeneous on polyacrylamide gel electrophoresis with and without sodium dodecyl sulfate. The molecular weight of the enzyme was estimated as 44, 000 by sodium dodecyl sulfate electrophoresis and as 177, 000 by sucrose density gradient centrifugation, indicating that the enzyme is tetrameric. Various properties of the enzyme from human liver are similar to those of the enzyme from rat liver, including its molecular weight, pH optimum, Km values for omithine, α-ketoglutarate and pyridoxal phosphate and specificity for amino acceptor from ornithine. The amino acid compositions of the two enzymes also have certain similarities, but the enzymes differ in electrophoretic mobility and antigenicity: the human enzyme moved more slowly to the anode, and on immunodiffusion analysis, the single precipitin lines formed between anti-human enzyme serum or anti-rat liver enzyme and the enzyme from human liver or lymphoblastoid cells and the rat liver enzyme fused with spur formation.抄録全体を表示PDF形式でダウンロード (1533K) -
Toshihiro SUGIYAMA, Nobuo MIKI, Yoshihiro MIYAKE, Toshio YAMANO1982 年 92 巻 6 号 p. 1793-1803
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe interaction and electron transfer between cytochrome b5 and cytochrome P-450B1 were investigated using the reconstituted p-nitroanisole O-demethylase system. Apocytochrome b5 was prepared from detergent-solubilized cytochrome b5 by the acid-butanone method. The apocytochrome b5 thus obtained has been substituted with several metalloporphyrin derivatives. The reconstituted system containing cytochrome b5 substituted with heme derivatives such as proto-, meso-, and deuteroheme exhibited demethylation activity at the maximum turnover rates of 94, 58, 30%, respectively, compared to that containing the native cytochrome b5, while neither apocytochrome b5 nor cobaltic protoporphyrin-cytochrome b5 displayed the activity. Kinetic analysis showed the formation of a 1:1 complex between cytochrome P-450B1 and each of these substituted cytochrome b5's, except for cobaltic protoporphyrin-cytochrome b5; the affinities differed with the cytochrome b5 species used. The synergistic effect with the addition of the NADH-linked electron transport system was more remarkable at the lower reduction levels of cytochrome b5 in the steady state. Interaction between the components involved in NADH- and NADPH-linked electron transport systems was modulated by the existence of Triton X-100. The optimal concentration in the reconstituted system for the demethylation was observed at around 0.03% of Triton X-100, where the reduction rates for cytochrome b5 and cytochrome P-450B1 by the respective reductases were maximal. These results indicate that the two electron transport systems are closely coupled and exhibit the demethylase activity.抄録全体を表示PDF形式でダウンロード (866K) -
Hidenori HAYASHI, Minoru NAKANO, Sigehiro MORITA1982 年 92 巻 6 号 p. 1805-1811
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe amino acid compositions, constituent polypeptides and bacteriochlorophyll (Bchl) contents of two kinds of Bchl-protein complexes isolated from Rhodopseudomonas palustris were examined. Spectrally dissimilar intracytoplasmic membranes obtained from cells cultured under different conditions were used as starting materials. The B 870-reaction center complex was consistent in its amino acid composition, constituent polypeptides and Bchl content, as well as in its near-infrared absorption spectrum. B 800-850 complexes from the different types of intracytoplasmic membrane varied in their absorption spectra, though they had similar amino acid compositions and were comprised of basically similar kinds of polypeptides with variations only in the levels of some minor constituent polypeptides. The B 800-850 complex with a low absorption peak at 850 nm had a Bchl content 1.3 times greater than the B 800-850 complex with a high absorption peak at 850 nm. These results indicate that the B 800-850 complex from R. palustris contains more components (both polypeptides and Bchl molecules) than the B 800-850 complexes from Rhodopseudomonas capsulata and Rhodopseudomonas sphaeroides.抄録全体を表示PDF形式でダウンロード (510K) -
Keiichiro HASHIMOTO, Keizo INOUE, Shoshichi NOJIMA, Takushi TADAKUMA, ...1982 年 92 巻 6 号 p. 1813-1821
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe relation between the in vitro immunogenicity of phosphatidylcholine liposomes containing 2, 4-dinitrophenyl-6-N-aminocaproylphosphatidylethanolamine (DNP-Cap-PE) as a hapten and the topographical distribution of the haptens on lipid membranes was studied. In distearoylphosphatidylcholine liposomes, the immunogenicity increased with increase of cholesterol content in the liposomal membranes. The electron spin resonance spectra of spin-labeled DNP-Cap-PE in distearoyl-phosphatidylcholine liposomes indicated that cholesterol affected the topographical distribution of spin-labeled DNP-Cap-PE on the membranes. In the absence of cholesterol, a considerable amount of haptens was clustered on the distearoyl-phosphatidylcholine membranes, but with increase of cholesterol, random distribution of the haptens on the membranes increased. The cholesterol-dependent change in the topographical distribution of the haptens on the membranes paralleled the change of immunogenicity, i.e., the immunogenicity was low when haptens were clustered on the liposomal membranes. Haptens arranged at a proper distance on the membranes may be required for optimum immune response.抄録全体を表示PDF形式でダウンロード (680K) -
Takahisa SHINOMIYA, Mariko KOBAYASHI, Showbu SATO, Tsuneko UCHIDA1982 年 92 巻 6 号 p. 1823-1832
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーWe previously reported that Thermus thermophilus 111 contained two restriction enzymes, Tth 111 I and Tth 111 II. The former does not cleave ØX 174 RFDNA and the latter does. We have now found another endonuclease activity able to cleave ØX 174 RFDNA in the cell extract of T. thermophilus 111.
The protein with this activity was purified in a homogeneous state by chromatography on cellulose phosphate, heparin-Sepharose 4 B and hydroxylapatite, successively. However, this endonuclease activity was always accompanied with Tth 111 I activity during the purification procedure and the purified protein also showed a strong Tth 111 I activity, suggesting that the Tth 111 I activity and the ØX 174 RFDNA-cleaving activity reside in a single molecule. The ØX 174 RFDNA-cleaving activity was enhanced more strongly with Mn2+ than with Mg2+ and seemed to be attributable to a relaxed specificity of Tth 111 I activity as seen in the cases of EcoRI* and BamHI* Thus we designated the ØX 174 RFDNA-cleaving activity Tth 111 I*.
The molecular weight of the protein with both Tth 111 I and Tth 111 I* activities was determined to be about 76, 000 by gel filtration on a Sephadex G-100 column and 39, 000 by SDS-polyacrylamide gel electrophoresis, suggesting the enzyme to be a dimer consisting of identical polypeptide chains.
The ØX 174 RFDNA sequences surrounding Tth 111 I* cuts were determined by the chain terminator method of Sanger et al. The results confirmed that Tth 111 I* recognized a degenerated form of the Tth 111 I recognition sequence, i.e., a sequence such that one of the specified nucleotides in the Tth 111 I recognition sequence, 5' GACN_??_NNGTC 3', was substituted with N (N stands for any of A, G, C, and T), such as 5' NACN_??_NNGTC 3', 5' GACN_??_NNNTC 3', 5' GACN_??_NNGNC, and so on (arrows indicate cleavage sites).抄録全体を表示PDF形式でダウンロード (3635K) -
Goro MIYAKODA, Takao NAKAMURA1982 年 92 巻 6 号 p. 1833-1843
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe Ca2+ ion dependency of electrically stimulated beating activity of isolated ventricular myocytes of adult rat was examined by using video recording and highspeed movie photography of the cellular contraction. The myocyte exhibited a transient positive inotropy on treatment with dextran-pCMB having a minimum molecular weight of 200, 000 and the maximum degree and initial velocity of contraction as measured from the movie photographs increased 1.8 and 2.2 times, respectively, as compared with those before dextran-pCMB treatment. Then the myocyte showed fibrillatory movement which was not a response to electric stimulation. These effects were similar to those caused by ouabain, and they were reversed by dithiothreitol. The sarcomere length of the myocyte in the resting state was reversibly shortened by treatment with dextran-pCMB only in the presence of added Ca2+. K+-PNPPase activity of the myocyte was inhibited by dextran-pCMB. It is suggested that dextran-pCMB binds to a protein factor (s) in the cytoplasmic membrane from the exterior of the myocyte to give rise to an increase of intracellular concentration of Ca2+.抄録全体を表示PDF形式でダウンロード (1447K) -
Junji SAGARA, Kazuhiro NAGATA, Yasuo ICHIKAWA1982 年 92 巻 6 号 p. 1845-1851
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe Mg2+ATPase activity of the myosin of a myeloid leukemia cell line (Ml) was not activated by purified Ml actin or by muscle actin alone. Activation required the presence of a cellular fraction as a cofactor in addition to the actin, when Mg2+ATPase was stimulated as much as 20-fold.
The cofactor was partially purified and characterized. 1) Its molecular weight was estimated as 45, 000 to 55, 000 daltons by gel filtration and as 45, 000 daltons by SDS polyacrylamide gel electrophoresis. 2) The cofactor was a light chain kinase that phosphorylated both the L1 and L2 light chains of the Ml cell myosin, but not the L3 or heavy chain.抄録全体を表示PDF形式でダウンロード (870K) -
Hiroshi HOSOYA, Issei MABUCHI, Hikoichi SAKAI1982 年 92 巻 6 号 p. 1853-1862
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーTwo groups of protein species which interact with G-actin were detected in unfertilized sea urchin eggs by DNase-I affinity chromatography in the presence of Ca2+ One of the protein groups, which comprised of six major proteins, was eluted by EGTA. One of these proteins was tentatively identified as calmodulin. The other protein group, comprising of four major proteins, could be dissociated from the immobilized DNase I at a higher ionic strength. One of these proteins, showing a molecular weight of 17, 000 (17 K protein), was purified to homogeneity. In its action on actin, 17 K protein revealed properties quite similar to those of a protein called depactin isolated from unfertilized starfish oocytes, but different from those of profilins isolated from mammalian tissues or Acanthamoeba. 17 K protein comigrated with depactin on an SDS-gel. It inhibited actin polymerization and quickly depolymerized F-actin. When added to G-actin before polymerization, 17 K protein suppressed the final extent of actin polymerization. This inhibition was not released by the addition of sonicated F-actin nuclei. When added to F-actin, 17 K protein rapidly reduced the viscosity and increased the G-actin concentration of the actin solution. In both cases, the final extent of actin polymerization strictly depended on the molar ratio of 17 K protein to actin, indicating a stoichiometric association between 17 K protein and actin.抄録全体を表示PDF形式でダウンロード (2371K) -
Masaaki KURODA1982 年 92 巻 6 号 p. 1863-1872
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーMuscle actin is, in most cases, prepared from an acetone-dried powder of the myosin-removed myofibrils under low-salt conditions in the presence of ATP. In this paper, it is shown that G-actin can be directly extracted from the myosin-removed myofibrils without acetone treatment. The extraction conditions are the same as those used for the extraction of G-actin from the dried powder: extraction of the myosin-removed myofibrils for 1 h with 2mM Tris-HCl, pH 8.0, in the presence of 0.5mM ATP. However, the crude G-actin directly extracted from the myosinremoved myofibrils loses its polymerizability after prolonged extraction. Measurements of inorganic phosphate and thin layer chromatography of the adenine nucleotides of the crude G-actin solution show that free ATP added to the extraction buffer is sequentially hydrolyzed to ADP and AMP, and then finally converted to IMP. The instability of the G-(ADP)-actin, depolymerized from the ends of actin filaments, explains the loss in polymerizability of G-actin during the extraction. Residual ATPase, adenylate kinase, and deaminase contained in the myofibrils may account for the decomposition of ATP.抄録全体を表示PDF形式でダウンロード (3519K) -
Isao CHINEN, Keiichi OOUCHI, Hajime TAMAKI, Nobuhiro FUKUDA1982 年 92 巻 6 号 p. 1873-1881
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThermostable β-xylosidase was purified from immature sugar cane stalks to an electrophoretically homogeneous form by ammonium sulfate fractionation, ionexchange chromatography on DEAE-cellulose and P-cellulose columns, heat treatment (70°C, 20min) and gel filtration on a Sephadex G-100 column. The purification was about 165-fold in specific activity with a high recovery of 43%. The apparent molecular weight of the enzyme, as determined by gel filtration, was 62, 000. In SDS-polyacrylamide gel electrophoresis, the purified enzyme was homogeneous and consisted of only one polypeptide, having a molecular weight of approximately 62, 000. The optimum temperature and pH were found to be 75°C and 4.85, respectively. The enzyme was thermostable and especially stable in the presence of D-xylose. The enzyme retained full activity after incubation at 70°C for 60min in the presence of 0.1% D-xylose and when heated at 75°C in the presence of 1 D-xylose, the enzyme was stable up to 30min. Among the various sugars tested, D-xylose was found to be most effective stabilizer. The Km and Vmax values were 2.05mM and 20.4 μmol/mg/min, respectively. The substrate specificity of purified sugar cane β-xylosidase was investigated with 16 substrates. It was not able to hydrolyze any p-nitrophenyl glycopyranosides, larch wood xylan, or sugar cane except for p- and o-nitrophenyl-β-D-xylopyranosides. The enzyme hydrolyzed p-nitrophenyl-β-D-xylopyranoside more rapidly than o-nitrophenyl-β-D-xylopyranoside. The hydrolysis of p-nitrophenyl-β-D-xylopyranoside was markedly inhibited by AgNO3, HgCl2, and D-xylose. Competitive inhibition was shown to occur with both HgCl2 and D-xylose. AgNO3 was found to be a non-competitive inhibitor. The enzyme lost 20% of its activity by photo-oxidation in the presence of methylen blue for 8 h. By polyacrylamide disc gel electrophoresis, the enzyme was found to contain carbohydrate. The enzyme was then hydrolyzed and the carbohydrate content found to be 13.5%, the constituent sugars being arabinose and galactose.抄録全体を表示PDF形式でダウンロード (1222K) -
Tamao ENDO, Shoshichi NOJIMA, Keizo INOUE1982 年 92 巻 6 号 p. 1883-1890
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe haptenic activity of Forssman glycolipid was affected by glycophorin, and the interaction of glycophorin with lectins was also affected by the glycolipids, when both glycophorin and Forssman glycolipid or globoside were incorporated into the same phosphatidylcholine liposomes. Glycophorin incorporated into phospholipid membranes could interact with lectins, whereas that in glyceroglycolipid membranes could not. These findings suggest that glycophorin and glycolipids may interact, affecting the conformation of their sugar residues, probably through a carbohydratecarbohydrate interaction. Such an interaction may cause suppression or stimulation of the reactivity of glycoconjugates with lectins or antibodies. Lactosylceramide showed only a slight effect on the interaction between glycophorin and lectins. We suggest that the structure of the sugar residues as well as the lateral distribution of molecules was important for the intermolecular interaction.抄録全体を表示PDF形式でダウンロード (625K) -
Shohko TSUNAWAKI, Den'ichi MIZUNO, Michihiro KASAHARA1982 年 92 巻 6 号 p. 1891-1900
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーA plasma membrane-rich fraction was prepared from guinea pig peritoneal polymorphonuclear leucocytes (PMNs) by a nitrogen cavitation method. Fc receptor activity was measured in the fraction. The activity showed a Kd of 5×10-7 M IgG and a maximum binding of 33 pmol IgG/mg protein when measured with an immune complex made with bovine serum albumin and rabbit anti-(bovine serum albumin) immunoglobulin G. Properties of the Fc receptor in the plasma membrane fraction were similar to that in intact PMNs. It is proposed that the Fc receptor activity and 5'-nucleotidase activity are markers for plasma membranes of these cells.抄録全体を表示PDF形式でダウンロード (736K) -
Takeyoshi IMAMURA, Kazue KONISHI, Katsutoshi KONISHI1982 年 92 巻 6 号 p. 1901-1910
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe molecular weights of acetylcholine receptor proteins from Narke japonica were determined using a combination of high-speed gel filtration and the low angle laser light scattering technique. The values obtained were 460, 000 and 240, 000 for the dimer and monomer, respectively. By use of a weakly charged silica gel column for high-speed gel filtration calibrated by considering electrostatic interactions between proteins and gel surfaces, the Stokes radii of the proteins were estimated as 7.3 nm and 6.2 nm. Chromatography in 6M guanidine hydrochloride (GmHCl) showed that the proteins were hardly dissociated to subunits, and CD measurements confirmed that the proteins are resistant to GmHCl denaturation. These results suggest that strong hydrophobic interactions exist among the receptor subunits and probably within the subunits themselves.抄録全体を表示PDF形式でダウンロード (1195K) -
Fumie YAMASAKI, Hidenori HAYASHI1982 年 92 巻 6 号 p. 1911-1917
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe effects of divalent cations on the induction of phosphodiesterase [EC 3. 1. 4. 17] by cyclic adenosine 3', 5'-monophosphate (cyclic AMP) were studied in Dictyostelium discoideum. When cells were incubated with 1mM ethylene glycol-bis (β-aminoethylether)-N, N, N', N'-tetraacetic acid (EGTA) in 20mM Tris-HCl buffer, pH 7.5, for 2 h, the induction of cellular phosphodiesterase was inhibited by about 80%, and that of extracellular phosphodiesterase by about 65%. When cells were incubated with 1mM EGTA for 1 h, 2mM CaCl2 was added and the cells were further incubated for 1 h, the activities of cellular and extracellular phosphodiesterases were increased about 5 and 2.5 times, respectively, compared with those in the EGTA-inhibited cells. Although various other kinds of divalent cations were also studied, Ca2+ had the greatest effect on the induction.
These results suggest that Ca2+ may participate in the induction of phosphodiesterase, and thus in the regulation of the development of the cellular slime mold.抄録全体を表示PDF形式でダウンロード (563K) -
Tadashi ASAKURA, Michio HOSHINO, Takaaki KOBAYASHI1982 年 92 巻 6 号 p. 1919-1923
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーBrain synaptosomes released endogenous γ-aminobutyric acid (GABA) in response to Ca2+. The release of GABA in response to 2.5mM Ca2+ increased linearly with log [K+]0, showing that a membrane potential-dependent Ca2+ channel limits the GABA release. In the presence of Ca2+ ionophore, A 23187, GABA release increased linearly with log [Ca2+]0 without altering the membrane potential of synaptosomes.抄録全体を表示PDF形式でダウンロード (396K) -
Toyoko KUWAHARA, Ikuyo YOSHIMOTO, Akio ITO1982 年 92 巻 6 号 p. 1925-1931
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリー1. The sulfite oxidases from various vertebrates, including rat, rabbit, chicken, frog, and eel, were partially purified and their physicochemical, kinetic, and immunochemical properties compared. The physicochemical and kinetic properties of these five enzymes were similar.
2. Antibody against the molybdenum-containing peptide prepared from purified rat liver sulfite oxidase was raised in rabbits. In Ouchterlony double diffusion and quantitative immunoprecipitation tests, the antibody could form precipitates with the enzymes from rats and rabbits, but no reaction was observed with enzymes from other sources.
3. The sulfite-cytochrome c reductase activity of the enzymes from these five animals were inhibited by the antibody, though the enzymes from chicken, frog, and eel were less sensitive to the antibody than those from rat and rabbit.
4. The inhibition of binding between 3H-labeled rat sulfite oxidase and its antibody by unlabeled enzymes from other animals demonstrated that 10 to 20% of the antibody could cross-react with these enzymes.抄録全体を表示PDF形式でダウンロード (1246K) -
Toshiharu MURAOKA, Takao ANDO, Hiromichi OKUDA1982 年 92 巻 6 号 p. 1933-1939
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーA novel lipase of Staphylococcus aureus 226 was purified by ammonium sulfate precipitation followed by successive chromatographies on hydroxylapatite, Sephadex G-200 and G-150. This method gave 385-fold purification of the enzyme from the culture medium in a yield of 25%. The purified enzyme appeared homogeneous on polyacrylamide gel ele_??_trophoresis and isoelectric focusing. The purified lipase hydrolyzed all the triacylglycerols and 1-monoacylglycerols tested, showing maximal activity with trilaurin and 1-monoolein. Furthermore, 2-monoolein was also found to be one of the best substrates for the lipase. The optimum temperature of the purified enzyme was 60°C with triolein. The molecular weight of the enzyme was reduced in the presence of sodium deoxycholate and was estimated as 34, 000 by gel filtration and its isoelectric point as 9.7. Mg2+ and Ca2+ ions enhanced the enzymatic reaction, whereas Mn2+ ions were inhibitory. p-Chloromercuribenzoate, iodoacetamide, and N-ethylmaleimide did not inhibit the enzyme.抄録全体を表示PDF形式でダウンロード (867K) -
Hiroshi SAKAMOTO, Miho OHTA, Retsu MIURA, Toshihiro SUGIYAMA, Toshio Y ...1982 年 92 巻 6 号 p. 1941-1950
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe existence of a multi-component equilibrium involving a reversible reaction was demonstrated in the anaerobic reaction of NADPH-adrenodoxin reductase or ferredoxin-NADPH reductase; EC 1. 18. 1. 2 (AdR) with NADPH or in the photoreduction of AdR in the presence of NADP+ and EDTA. After anaerobic reduction of AdR with excess NADPH, not only the fully reduced state but also other states of the enzyme were demonstrated as a mixture of characteristic absorption spectra of a flavin semiquinone with a peak at 575 nm and a shoulder around 625 nm and a charge transfer complex between NADP+ and the fully reduced AdR with a broad absorbance in a longer wavelength region. The amount of oxidized form in the reaction mixture was only a trace judging from the absorbance at 450 nm. The oxidized form was observed in addition to the other spectral species when the concentration of NADPH was limited. The spectrum of the AdR reduced with excess NADPH changed reversibly between 2°C and 29°C with isosbestic points at 427 nm and 667 nm; the semiquinone form increased at the expense of the charge transfer complex at lower temperatures, and vice versa at higher temperatures.
The anaerobic photoreduction of AdR in the presence of NADP+ and EDTA produced the same spectral species as seen in the NADPH-reduced AdR, and the spectrum of the photoreduced AdR also changed reversibly between 1°C and 33°C in a similar way to that of the NADPH-reduced AdR; the oxidized form changed in parallel with the semiquinone form. It was also found that NADPH was produced continuously during the photoirradiation even after the spectral changes had ceased.
The results show that anaerobic reduction of AdR with NADPH or the photoreduction of AdR in the presence of NADP+ and EDTA produces a multi-component equilibrium and the equilibrium is dependent upon the concentration of NADPH and the temperature. Attainment of the equilibrium involves not only the forward reaction of AdR with NADPH but also the reverse reaction of the fully reduced AdR with NADP+.抄録全体を表示PDF形式でダウンロード (824K) -
Masayuki KANDA, Kazuko HORI, Setsuko MIURA, Yoko YAMADA, Yoshitaka SAI ...1982 年 92 巻 6 号 p. 1951-1957
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーIn gramicidin S synthetase 2 (GS 2) from Bacillus brevis, L-proline, L-valine, L-ornithine, and L-leucine activations to aminoacyl adenylates are progressively inhibited by phenylglyoxal. The inactivation of GS 2 obeys pseudo-first-order kinetics. ATP completely prevents inactivation of GS 2 by phenylglyoxal, whereas amino acids only partially prevent it. In the presence of ATP, four arginine residues per mol of GS 2 are protected from modification by phenylglyoxal as determined by amino acid analysis and the incorporation of [7-14C] phenylglyoxal into the enzyme protein, indicating that a single arginine residue is necessary for each amino acid activation.
In isoleucyl tRNA synthetase from Escherichia coli, phenylglyoxal inhibits activation of L-isoleucine to isoleucyl adenylate. ATP completely prevents inactivation, although isoleucine only partially prevents it. One arginine residue of isoleucyl tRNA synthetase is protected by ATP from modification by phenylglyoxal, suggesting that a single arginine residue is essential for isoleucine activation.
These results support the involvement of arginine residues in ATP binding with GS 2 or isoleucyl tRNA synthetase, and thus indicate that arginine residues of amino acid activating enzymes are essential for the formation of aminoacyl adenylates in both nonribosomal and ribosomal peptide biosynthesis.抄録全体を表示PDF形式でダウンロード (567K) -
Shohei MAEKAWA, Sachiko ENDO, Hikoichi SAKAI1982 年 92 巻 6 号 p. 1959-1972
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーFrom an extract of starfish sperm heads, a protein was purified using ammonium sulfate fractionation, Sephacryl S-300, hydroxyapatite and Whatman DE 52 columns. Co-sedimentability on low speed centrifugation of this protein with actin filaments was used as an index in the purification. This protein has a molecular weight of 57, 000, as judged by SDS-polyacrylamide gel electrophoresis. It lowers the specific viscosity of an actin filament solution, although this effect is abolished under high ionic conditions such as 300mM NaCl. Electron microscopic observation shows formation of actin filament bundles with a banding pattern of about 10 nm periodicity. Based on these results, we call this protein starfish sperm fascin. Changes in pH and Mg2+ or ATP concentration have no effect on the action of this sperm fascin. Neither the rate of actin polymerization nor that of depolymerization is affected by this protein. The bundles are depolymerized as well by actin-depolymerizing protein (Mabuchi, I. (1981) J. Bioehem. 89, 1341-1344) purified from starfish eggs.抄録全体を表示PDF形式でダウンロード (5729K) -
Mitsuo IKEBE, Satoshi OGIHARA1982 年 92 巻 6 号 p. 1973-1977
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーWe observed the fine structure of myosin filament bundles in 10mM MgCl2 and studied the effects of light chain phosphorylation on it by electron microscopy. In the filament bundles of dephosphorylated myosin in the presence of ATP, we found a striation pattern of 13.4 nm periodicity running perpendicularly to the long axis of the filaments. However, we did not observe such a pattern in filament bundles of phosphorylated myosin even when exposed to ATP, but many irregularly arranged projections were seen on their surface.
The 13.4 nm period of the striation was so close to the dimension of myosin heads that it seems likely that the striation pattern represents the regular array of myosin heads, which is a consequence of conformational changes in dephosphorylated myosin molecules upon reacting with ATP.抄録全体を表示PDF形式でダウンロード (1391K) -
Masahiko MATSUMOTO, Masaichi YAMAMURA, Michio TSUDA, Shigeo TAKADA, Ts ...1982 年 92 巻 6 号 p. 1979-1983
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe relationship between chymotrypsin-inhibitory and immunoenhancing activity of α-1-antichymotrypsin was studied. α-1-Antichymotrypsin was treated at 50°C, 55°C or 60°C for 15min. It was found that antichymotryptic activity was reduced by half when α-1-antichymotrypsin was heated at 55°C and was not detected at all when heating was carried out at 60°C. α-1-Antichymotrypsin which was heated at 60°C did not form a complex with chymotrypsin, but became a substrate for chymotrypsin. The effect of native and heated α-1-antichymotrypsin on antibody response was studied in mice. α-1-Antichymotrypsin increased the number of anti-sheep erythrocytes antibody producing cells even when it was heated at 60°C. Circular dichroism and single radial immunodiffusion were used to detect conformational changes. Circular dichroism in the region of side chain absorption showed that the intensities of the spectra at 296, 284, and 265 nm decreased with a rise in temperature from 50 to 60°C. In single radial immunodiffusion analysis, α-1-antichymotrypsin did not form a halo after being heated at 60°C.
In conclusion, when α-1-antichymotrypsin was heated at 60°C, the immunoenhancing activity remained intact while the antichymotryptic activity was lost with the conformational change.抄録全体を表示PDF形式でダウンロード (394K) -
Yoshifumi HORIUTI, Toshikazu NAKAMURA, Akira ICHIHARA1982 年 92 巻 6 号 p. 1985-1994
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーSerum at 5 to 10% is required for maintenance of functional adult rat hepatocytes in primary culture. One effect of the serum is to induce attachment and spreading of hepatocytes on plates as monolayers. Another role is to maintain cell viability for over 2 days. For the first effect, serum could be replaced completely by fibronectin (Fn). The effects of Fn on attachment and spreading of cells were dosedependent and maximum at 10 μg/ml. Cells in serum-free medium on Fn-coated dishes showed similar activities of glycogenolysis and glycogenesis to cells cultured in medium containing 5% calf serum on untreated dishes in response to glucagon, dibutyryl cyclic AMP (bt2c AMP), isoproterenol and insulin. The increase in alkaline phosphatase [EC 3. 1. 3. 1] activity and induction of tyrosine aminotransferase [EC 2. 6. 1. 5] by dexamethasone (Dex) in cells under the two conditions were also similar. However, the inductions of tryptophan oxygenase [EC 1. 13. 11. 11] by Dex, glucagon, and bt2cAMP were 4-7 times higher in cells cultured in serumfree medium. The inductions by Dex plus glucagon in the two types of cultures were inhibited similarly by insulin.
In serum-free medium containing Dex and insulin in Fn-coated dishes, the cells survived as monolayers for about 50 h without detachment from the dishes, but for longer survival it was necessary to add 5% serum to the medium. A fraction with a molecular weight of over 50, 000 from serum was separated by ultrafiltration and this fraction showed a similar effect to serum in increasing survival. A similar factor, but with about 70 times higher specific activity, was found in an extract of bovine pituitary gland.抄録全体を表示PDF形式でダウンロード (1546K) -
Tomoko HAYASHI, Yoshihide OHE, Hiroaki HAYASHI, Koichi IWAI1982 年 92 巻 6 号 p. 1995-2000
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe amino acid sequence of human spleen histone H 4 was investigated as part of a study on histone evolution, following previous investigations of human spleen histones H 2 B (J. Biochem. 85, 615-624), H 2 A (J. Biochem. 88, 27-34), and H 3 (J. Biochem. 90, 1205-1211). The H 4 fraction was obtained as described previously and further purified by Bio-Gel P-60 chromatography. The purified H 4 was digested with trypsin and the peptides were fractionated by repeated column chromatographies with reasonable recoveries. Certain peptides were sequenced, and three modified residues (α-N-Ac-Ser-1, ε-N-Ac-Lys-16, and ε-N-Me-Lys-20) and one heterogeneous residue (Asn/Asp-25), which is probably a result of postsynthetic deamidation, were found. Thus, the human H 4 was deduced to have a sequence of 102 amino acid residues completely identical with that of calf thymus H 4, including the presence of three modified residues and the absence of any variant sequence. It is concluded that the animal H 4 sequences and their postsynthetic modifications have been strongly conserved during the evolutionary process leading to man, as strongly as or more strongly than the H 3 sequence, and much more strongly than the H 2 A and H 2 B sequences.抄録全体を表示PDF形式でダウンロード (376K) -
Koshi SAITO, Kunihiro YAMAMOTO, Takaji TAKAI, Sho YOSHIDA1982 年 92 巻 6 号 p. 2001-2007
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe I- transport system in the thyroid plasma membrane (PM) was successfully reconstituted in phospholipid vesicles (P-vesicles) by sonication. P-vesicles thus prepared were able to concentrate I- in the presence of external Na+. The activity of the I- transport increased with increase in the Na+ concentration outside the P-vesicles and with graded doses of PM protein used for the reconstitution in P-vesicles. When P-vesicles were prepared with only the lipid components extracted from PM instead of total PM, they were deprived of the biological activity to accumulate I-. Methimazole (MMI) did not change the Na+-dependent I- transport, but ClO4- and SCN- had inhibitory effects on the transport.
These observations indicate that 1) a specific I- translocator is present in the thyroid PM, 2) the translocator is easily reconstituted in P-vesicles, 3) the translocator may not consist of phospholipids despite the theory of the I--concentrating thyroid phospholipids, and 4) Na+-I- cotransport through the translocator may be the mechanism for the accumulation of I- in the thyroid cells.抄録全体を表示PDF形式でダウンロード (520K) -
Mototeru YAMANE, Isamu YANAGISAWA1982 年 92 巻 6 号 p. 2009-2020
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーOne of the authors reported previously on the presence of 1-methylheptyl γ-bromoacetoacetate (MHBAA) in human cerebrospinal fluid. In this work, a microdetermination of MHBAA in human blood plasma was developed.
The sulfhydryl group of 5-(dimethylamino)-1-naphthalene-sulfonyl L-cysteine (DANSYL L-cysteine) reacted with Br at the γ-position of MHBAA to form a thioether bond, and a fluorescent derivative was obtained. The fluorescent derivative was separated by TLC. Quantitative determination of MHBAA was done by the radiodilution method combined with fluorometry. It was shown that MHBAA exists in human blood plasma at a concentration of several hundred pmol per ml.抄録全体を表示PDF形式でダウンロード (1714K) -
Emiko TAKANO, Takashi MURACHI1982 年 92 巻 6 号 p. 2021-2028
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーCalpastatin, an endogenous inhibitor protein specifically acting on calpain [EC 3. 4. 22. 17; Ca2+-dependent cysteine proteinase], was purified to apparent homogeneity from the cytosol fraction of human erythrocytes. The yield was 0.38mg from 400ml of blood. The purification procedures included DEAE-cellulose and Ultrogel AcA 34 gel chromatographies followed by heat treatment and a final gel chromatography on Sephacryl S-200, from which calpastatin was eluted at a position corresponding to a 280, 000-dalton molecular mass. The heat treatment at 100°C for 15min at pH 7.5 very effectively removed contaminant proteins. The homogeneity of the final product was demonstrated on polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate, giving a single protein band with a calculated molecular weight of 70, 000. After re-extraction from the gel, the 70, 000-dalton protein readily reassociated to give a 280, 000-dalton peak upon Sephacryl S-200 chromatography with a recovery of total inhibitory activity of 42%. Purified calpastatin had an isoelectric point at pH 4.55. It had glutamine as the amino-terminal residue. Amino acid analyses revealed that it contained relatively large amounts of proline, glutamic acid, and lysine, smaller amounts of aromatic amino acids, notably no tryptophan, and no amino sugars. The content of half-cystine was less than one per 643 amino acid residues. These features are in general agreement with those of the reported amino acid composition of Ca2+-protease inhibitor from chicken skeletal muscle [Ishiura et al. (1982) Biochim. Biophys. Acta 701, 216-223], although these inhibitors were found to be definitely different in several other respects. Human erythrocyte calpastatin could inhibit not only calpain of the same origin but also calpains having low and high Ca2+-sensitivity from rat liver.抄録全体を表示PDF形式でダウンロード (1305K) -
Theodore B. KTENAS, Nikolaos G. OIKONOMAKOS, Theodore G. SOTIROUDIS, S ...1982 年 92 巻 6 号 p. 2029-2033
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーA number of aliphatic amines was shown to stimulate AMP-dependent activity of phosphorylase b. The extent of stimulation depends on the molecular structure of amines. For linear amines, the longer the linear chain, the greater the stimulation observed. High concentrations of amines were able to induce a small activation of phosphorylase b in the absence of AMP. Kinetic studies of phosphorylase b indicated that the presence of n-hexylamine (a) results in lowering Km values for AMP and glucose 1-phosphate, (b) increases maximal velocity of the enzyme, and (c) modifies the glucose 6-phosphate, ATP, caffeine, and glucose binding sites of the enzyme by increasing the inhibition constants for these inhibitors. In contrast, the activity of phosphorylase b' is not altered by n-hexylamine. This fact suggests the possibility that amines interact with the N-terminal tail of phosphorylase b chain.抄録全体を表示PDF形式でダウンロード (364K) -
Peter BELLEMANN1982 年 92 巻 6 号 p. 2035-2038
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーHepatocytes from neo- and postnatal rat liver were isolated, purified from nonhepatocytes (erythropoietic cells), and cultured in sufficient quantity to investigate enzyme inducibility. Tyrosine aminotransferase (TAT) in neo- and postnatal hepatocytes was induced by maximally responsive doses of glucagon, dexamethasone, DB-cAMP, theophylline, and combinations thereof. In cultures from newborn parenchymal cells TAT enzyme-specific activity showed only a moderate inducibility; however, responsiveness to the combination was fully developed 10 days after birth and did not differ from values found in adult liver cells. The results also show the existence of the “permissive” effect of glucocorticoid during postnatal age, and indicate that the development of a possibly involved receptor complex for the induction of TAT is largely completed 5-10 days after birth.抄録全体を表示PDF形式でダウンロード (350K) -
Akira MURAYAMA, Fumio FUKAI1982 年 92 巻 6 号 p. 2039-2042
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe molecular mechanism of the translocation of estrogen receptor (ER) from the cytoplasm into the nucleus was studied in an in vitro system taking into account the specific interactions of the basic constituents of the uterine ER-system which had been reported previously (Murayama, A. et al. (1980) J. Biochem. 88, 1457). It was found that ER is translocated from the cytoplasm into the nucleus in the form of veto-ER•estradiol (basic ER-unit bound with estradiol; sedimentation coefficient, 4.5 S; Stokes radius, 44 A; Kd for estradiol, _??_10-10M) dissociated from coexisting estrogen receptor-binding factors (ERBFs). ERBFs inhibited the translocation of vero-ER into nuclei through binding with it. The apparent equilibrium dissociation constants (Kd) of ERBFs for vero-ER were estimated by Scatchard analysis to be 2.6×10-10M [“5 S” ER-forming factor (“5 S” ER-FF)], 3.0×10-9M (“6 S” ER-FF), and 2.5×10-9M (“8 S” ER-FF), respectively. The inhibitory effects of ERBFs on the binding of vero-ER to the nucleus paralleled their association constants.抄録全体を表示PDF形式でダウンロード (240K) -
Kazuhiko KINOSITA, Jr., Akira IKEGAMI, Masasuke YOSHIDA, Yasuo KAGAWA1982 年 92 巻 6 号 p. 2043-2046
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーThe soluble portion (TF1) of proton-translocating ATPase from thermophilic bacterium PS 3 was labeled with a fluorescent dye N-(1-pyrene) maleimide. The decay of fluorescence anisotropy of the adduct showed that TF1 in aqueous solution was characterized by a volume of equivalent sphere of 1, 120 nm3. This value is 2.4 times the volume calculated from the molecular weight and partial specific volume, indicating a non-spherical shape and/or extensive hydration. A prolate ellipsoid with an axial ratio of 2 to 3 is suggested as a first approximation of the shape of hydrated TF1. The presence or absence of ATP, ADP, or Mg2+ did not alter the volume of the equivalent sphere appreciably; the probable conformational change of TF1 induced by these ligands does not lead to a gross alteration of its hydrodynamic properties.抄録全体を表示PDF形式でダウンロード (284K) -
Kenji MOMOTA, Khoji SHIMODA, Masaharu NAIKI1982 年 92 巻 6 号 p. 2047-2050
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーHuman lymphoid cell lines were established from the peripheral lymphocytes of persons with different P blood group phenotypes by in vitro transformation with EB virus. The glycosphingolipid compositions of these cell lines were examined by TLC. The results show that P1k and P2k phenotype cells lack globoside (P antigen) and that two cell lines established from persons with the p phenotype lack both globoside and CTH (Pk antigen), while both the glycosphingolipids were detected in two cell lines established from persons with usual phenotypes (P1 or P2 phenotype). CTH synthetase activity was detected at decreased levels in two p phenotype cell lines, however, globoside synthetase activities could not be significantly detected in all the P phenotype cells.抄録全体を表示PDF形式でダウンロード (1134K) -
Michinao MIZUGAKI, Tomoko NISHIMAKI, Hirotaka YAMAMOTO, Mataichi SAGI, ...1982 年 92 巻 6 号 p. 2051-2054
発行日: 1982/12/01
公開日: 2008/11/18
ジャーナル フリーAlterations in the activities of enoyl-CoA hydratase, 3-hydroxyacyl-CoA epimerase, and 2, 4-dienoyl-CoA reductase in rat liver mitochondria and peroxisomes caused by clofibrate were compared in order to clarify the metabolic pathways for unsaturated fatty acids. Our results suggest that there are two pathways for fatty acids having (a) double bond (s) at the even-numbered carbon atom (s) both in mitochondria and in peroxisomes. One is the hydratase-epimerase participating pathways, and the other is the reductase participating pathway. It is considered that the former in mitochondria occurs mainly under normal conditions, and the latter becomes significant when the degradation of fatty acids is stimulated.抄録全体を表示PDF形式でダウンロード (250K) -
1982 年 92 巻 6 号 p. 2055a
発行日: 1982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 (23K) -
1982 年 92 巻 6 号 p. 2055b
発行日: 1982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 (23K)
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