巻号一覧
101 巻, 3 号
選択された号の論文の34件中1～34を表示しています
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Xian-Ming QU, Chun-Fa ZHANG, Hiroto KOMANO, Shunji NATORI1987 年 101 巻 3 号 p. 545-551
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA lectin with affinity to galactose was purified to homogeneity from the hemolymph of diapausing pupae of the Chinese oak silk moth, Antheraea pernyi. The molecular mass of this lectin was 380, 000 and it formed an oligomeric structure of a subunit with a molecular mass of 38, 000. The hemagglutinating activity in the hemolymph was found to increase with time after immunization with E. coli. Studies with antibody against the purified lectin showed that increase in the hemagglutinating activity was due to the same lectin, suggesting that the amount of the lectin increased in response to intrusion of foreign substances. The function of this lectin in the defence mechanism is discussed.抄録全体を表示PDF形式でダウンロード (1031K) -
Michiko SEKINE, Minoru SUZUKI, Fuyuhiko INAGAKI, Akemi SUZUKI, Tamio Y ...1987 年 101 巻 3 号 p. 553-562
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーTwo neutral glycolipids carrying the stage specific embryonic antigen-1 (SSEA-1) and SSEA-3 determinants, respectively, were purified from mouse kidney by a combination of column chromatographies and droplet counter-current chromatography. The structures of the glycolipids (GL-X and GL-Y) were determined by means of GLC, 1H-NMR spectroscopy, negative-ion fast atom bombardment mass spectrometry, a methylation study, and sequential degradation. GL-X was demonstrated to be galactosylβ1-3globotetraosylceramide, the structure of which had already been characterized to be that of SSEA-3 by Kannagi et al. ((1983) J. Biol. Chem. 258, 8934-8942). GL-Y was a new glycolipid containing fucose, galactose, glucose, N- cetylgalactosamine, and N-acetylglucosamine in a molar ratio of 1:4:1:1:1. The methylation study results indicated that it contained 3 mol of terminal sugars composed of 2 mol of galactose and 1 mol of fucose with two branching points at N-acetylgalactosamine and N-acetylglucosamine. From the data obtained by 1H-NMR spectroscopy, mass spectrometry, and a binding assay using an antiSSEA-1 monoclonal antibody (PM81) cloned by Ball et al. ((1983) J. Immunol. 130, 2937-2941), we propose the structure of GL-Y to be
Galβ1-4GlcNAcβ1-6GalNAc/β1-3Galα1-4Galβ1-4Glcβ1-ceramide. 3-Fucα1 3-Galβ1
This is the first report on the isolation and characterization of a glycolipid carrying the SSEA-1 determinant on its globo-core structure.抄録全体を表示PDF形式でダウンロード (2588K) -
Michiko SEKINE, Tamio YAMAKAWA, Akemi SUZUKI1987 年 101 巻 3 号 p. 563-568
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーIn the preceding paper (J. Biochem. 101, 553-562 (1987)), we reported the structures of two neutral glycolipids (GL-X and GL-Y) purified from mouse kidney, and demonstrated the occurrence of polymorphic variation of these two glycolipids in inbred strains of mice. GL-X was characterized as galactosyljlβ1-3globotetraosylceramide, which was reported to be stage specific embryonic antigen-3 (SSEA-3) by Kannagi et al. (J. Biol. Chem. 258, 8934-8942 (1983)), and GL-Y as 3-fucolactosaminylβ1-6(galactosylβ1-3) globotetraosylceramide, which carries the SSEA-1 eterminant. In order to elucidate the mode of genetic control of GL-X and GL-Y expression, two variants, i.e., BALB/c mice expressing GL-Y and DBA/2 mice lacking GL-Y but expressing GL-X as the major neutral glycolipid, were subjected to mating experiments and glycolipid analysis. F1 hybrids expressed GL-Y, therefore GL-Y expression is dominant, and DBA/2 mice were determined to be recessive homozygotes. Through analysis of backcross and F2 mice, DBA/2 mice were demonstrated to carry a single defective autosomal gene, and it is concluded that because of this DBA/2 mice cannot express GL-Y and so accumulate GL-X. An attempt to map the gene controlling GL-Y expression on mouse chromosomes using coat colors and recombinant inbred strains was not successful.抄録全体を表示PDF形式でダウンロード (1735K) -
A. S. N. REDDY, B. W. POOVAIAH1987 年 101 巻 3 号 p. 569-573
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe effect of inositol 1, 4, 5-trisphosphate (IP3) on Ca2+ release from microsomes of corn coleoptiles was investigated. Addition of micromolar concentrations of IP3 to Ca2+ loaded microsomes resulted in rapid release of 20-30% of sequestered Ca2+. Maximal and half maximal Ca2+ release occurred at 20 and 8μM of IP3 respectively. Part of the Ca2+ released by IP3 was reaccumulated into microsomes within 4min. The amount of Ca2+ released by IP3 was found to be dependent on free Ca2+ concentration in the incubation medium at the time of release. Maximum Ca2+ release was observed around 0.1 μM free Ca2+ concentration in the assay medium. These data suggest that IP3 might act as a second messenger in plants in a manner similar to animal systems by altering cytosolic levels of calcium.抄録全体を表示PDF形式でダウンロード (390K) -
Taiji IMOTO, Kiyotaka OKAZAKI, Hironobu KOGA, Hidenori YAMADA1987 年 101 巻 3 号 p. 575-580
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe specificity of highly purified rat liver cathepsin D was investigated by analyzing the digests of denatured proteins. At the P1 site, cathepsin D prefers hydrophobic residues except Ile and Val, that are branched at the β-carbon. Strong and weak hydrophobicities are required at P1' and P2 sites, respectively. A lower protency for β-turn formation is essential for the sequence around the P1 site.抄録全体を表示PDF形式でダウンロード (391K) -
Retsu MIURA, Yoshihiro MIYAKE1987 年 101 巻 3 号 p. 581-589
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーD-Amino acid oxidase (DAO) from porcine kidney was reconstituted with FAD's which were enriched with 13C at the 2-, 4-, 4a-, and lOa-positions of the isoalloxazine moiety, and 13C-NMR spectra of the reconstituted DAO were measured in the absence and presence of various competitive inhibitors. When compared to the corresponding chemical shifts of FMN at infinite dilution (Moonen, C. T. W. et al. (1984) Biochemistry 23, 4859-4867), the resonances of C (2), C (4), C (4a), and C (1Oa) of FAD bound to apoDAO were all shifted to higher field. However, when the reconstituted DAO was complexed with o-, m-, p-aminobenzoate, or benzoate, each of the four 13C-signals underwent a different change in chemical shift. In these changes we observed no characteristics which distinguish DAO-aminobenzoate complexes from DAO-benzoate complex, even though o-, m-, and p-aminobenzoates are known to form charge-transfer complexes with DAO. The signals due to 2- and 4-13C were more sensitive to the formation of the inhibitor-DAO complexes than those of the other carbon atoms. These findings suggest the modulation of the hydrogen bonds at the oxygen atoms of C(2)=O and C(4)=O with the protein moiety as the result of the inhibitor-binding.抄録全体を表示PDF形式でダウンロード (681K) -
Tokio TANI, Ichiro KAWASHIMA, Hidehiko FURUKAWA, Toshinori OHMINE, Yo ...1987 年 101 巻 3 号 p. 591-599
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA cDNA for porcine pancreatic elastase I has been cloned and used as a probe for blot hybridization analysis. Southern blot analysis of total DNA demonstrated that the elastase I gene is conserved among the porcine, rat, calf, and human genomes. Northern blot analysis, however, indicated that the elastase I gene is not expressed in the human adult pancreas, even though abundant expression is observed in the rat and porcine pancreas. Sequence analysis of the cloned human elastase I gene revealed that the proximal 5'-flanking region from -1 to -200 shows 78% identity with that of the actively transcribed rat elastase I gene, and contains a consensus TATA box and a putative tissue specific enhancer sequence. The transcriptional activity of the human elastase I gene appears to be suppressed in the human adult pancreas.抄録全体を表示PDF形式でダウンロード (1281K) -
Neutrophils Become Refractory to Phorbol Myristate Acetate When Treated with Ca2+-Ionophore and Ca2+Miwako NAKAGAWARA, Koichiro TAKESHIGE, Satoru SENJU, Junichi YOSHITAKE ...1987 年 101 巻 3 号 p. 601-608
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーHuman neutrophils deprived of divalent cations by treatment with ionophore A23187 in the presence of ethylene glycol bis (β-aminoethylether)-N, N, N', N'-tetraacetic acid (EGTA) showed superoxide release when they were preincubated with calcium and then treated with the ionophore. The release was not observed when the ionophore was added first and then calcium was added more than 5 min later. The absence of the release in this case can be ascribed to a refractoriness of the cells to stimuli, because the cells did not release superoxide on stimulation with phorbol myristate acetate (PMA). The cells pretreated with either calcium or the ionophore alone did release superoxide on addition of PMA. The refractoriness of the cells to PMA depended on the concentrations of calcium and the ionophore and on the time interval between the two treatments. Calcium could be replaced with Cd2 but not with Mg2+, Ba2+, or Sr2+. The release of granular enzymes was observed when the depleted cells were pretreated with the ionophore and then with calcium. These observations indicate that calcium has dual effects on the superoxide release of neutrophils, i.e., it stimulates the cells and makes them refractory to stimuli, depending on the time interval after the addition of the ionophore, and it also regulates the enzyme release by a different mechanism.抄録全体を表示PDF形式でダウンロード (624K) -
Nobuhiko ASHINO, Kenji SOBUE, Yoshiki SEINO, Hyakuji YABUUCHI1987 年 101 巻 3 号 p. 609-617
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA protein with a molecular weight of 80 kDa, which binds Ca2+-dependently to actin, was purified chromatographically from bovine adrenal medulla by using Sephacryl S-300, DEAE-Sepharose, actin-DNase I Sepharose, and Sephacryl S-200. This protein was retained on an actin-DNase I affinity column only in the presence of Ca2+, and could be eluted from this column by EGTA. The 80 kDa protein is a monomer and binds to G-actin in a Ca2+-dependent manner at an equimolar ratio. It caused fragmentation of actin filaments at more than 4×10-7 M free Ca2+ concentration, as determined by low-shear viscometry and electron microscopy. Saturating amounts of tropomyosin showed a slight protective effect on the fragmentation of actin filaments by the 80 kDa protein. Considering the mode of action on actin filaments, the 80 kDa protein reported here seems to be a gelsolin-like protein. Gel electrophoresis of this protein revealed changes in mobility depending upon the concentration of Ca2+. This result also indicates that the 80 kDa protein itself is a Ca2+-binding protein.抄録全体を表示PDF形式でダウンロード (2601K) -
Mitsuo TANAKA, Toshihiro IIO, Toshikazu TABATA1987 年 101 巻 3 号 p. 619-624
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーCarboxylesterase [EC 3. 1. 1. 1] was purified from rabbit liver lysosomes by means of detergent solubilization, and by hydroxyapatite, phenyl-Sepharose and chromatofocusing column chromatographies. The purified enzyme appeared to be homogeneous on SDS-polyacrylamide gel electrophoresis and its molecular weight was estimated to be 58, 000. This enzyme was eluted at an isoelectric point of approximately 5.8 by chromatofocusing, and exhibited a broad pH optimum of between 6.0 and 9.0. The enzyme hydrolyzed 4-methylumbelliferyl esters of saturated fatty acids (C2-C12), and it also hydrolyzed p-nitrophenylacetate, methyl butyrate, and tributyrin, but not acetanilide. Its activity was completely inhibited by diisopropylfluorophosphate (DFP) and phenylmethylsulfonyl fluoride (PMSF) at 10-4M, but was not affected by eserine, or by α- or β-naphthyl acetate at 10-3M. Various metal ions (Mg2+, Mn2+, Ca2+, Co2+, Cu2+, Zn2+, Ni2+) at 10-3M also had no effect on the enzyme activity.抄録全体を表示PDF形式でダウンロード (909K) -
Kazuhiko HORIGOME, Makio HAYAKAWA, Keizo INOUE, Shoshichi NOJIMA1987 年 101 巻 3 号 p. 625-631
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーIt was found that phospholipase A2 and lysophospholipase, both of which were released from thrombin-stimulated rat platelets, had high affinity to insolubilized heparin. Phospholipase A2 released from rat platelets was purified by the sequential use of column chromatography on heparin-Sepharose and TSK gel G2000SW (highperformance liquid chromatography, HPLC). The enzyme was near homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and HPLC, and its Mr was estimated to be 13, 500. The purified enzyme was labile and lost its activity within 1h when incubated at 37°C. Phospholipids or detergent in the solution protected the enzyme against inactivation. Phospholipase activity was inhibited by p-bromophenacylbromide, but not by diisopropylfluorophosphate or iodoacetamide. Lysophospholipase, which was also released from rat platelets, was separated from phospholipase A2 by chromatography on heparin-Sepharose.抄録全体を表示PDF形式でダウンロード (1028K) -
Hiroshi SAKAI, Takahisa OHTA1987 年 101 巻 3 号 p. 633-642
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーAllosteric activation of pyruvate kinase from a thermophilic bacterium, Bacillus stearothermophilus, by ribose 5-phosphate (R5P) was kinetically examined. Two activated forms of this enzyme could be distinguished, depending on the R5P concentration. One form (Form I) was observed at about 10-5 MR5P. It showed a slightly negative cooperativity for phosphoenolpyruvate (PEP). The other form (Form II) was observed at more than 10-3 MR5P and showed Michaelis-Menten kinetics for PEP. The PEP and ADP concentrations that yield half-maximal velocity were essentially identical for the two forms (about 0.1 and about 0.5mM, respectively), but Form I had a larger Vmax value than Form II. In the absence of R5P, the enzyme showed a homotropic positive cooperativity for PEP; the concentration required for the half-maximal velocity was about 2mM and that of ADP was about 1.6mM. The enzyme was more susceptible to protease digestion in the presence of R5P than in the absence of it. The concentration of R5P required for the enzyme to be susceptible to protease digestion was approximately identical with that required to generate Form I. With more than 10-3M R5P, the thermostability of the enzyme was greatly increased. The concentration of R5P required for the enzyme to be thermostable was in good agreement with that required to generate Form II. These results indicate that the two activated forms distinguished kinetically differ in their conformations, too. The saturating level of PEP did not cause such a change in the thermostability or the susceptibility to protease.抄録全体を表示PDF形式でダウンロード (1366K) -
Tsutomu MASUDA, Masako SAKAMOTO, Izumi NISHIZAKI, Hideyuki HAYASHI, Ma ...1987 年 101 巻 3 号 p. 643-652
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA rapid and simple method was developed for the purification of serine hydroxymethyltransferases [EC 2. 1. 2. 1]. The procedure involved ammonium sulfate precipitation, DEAE-cellulose column chromatography and affinity chromatography on an L-adsorbent. Through this procedure the cytosolic enzyme (s-SHMT) was purified 1, 650-fold, and the mitochondrial enzyme (m-SHMT) 1, 730-fold, with a yield of more than 30% in both cases. Both preparations gave a single band with a Mr of 54, 000 on SDS-PAGE. The native enzymes both contained 4 mol of pyridoxal phosphate/mol of enzyme, and showed a Mr value of 220, 000 on gel filtration, indicating a tetrameric structure. Several other properties of the enzymes were also studied.抄録全体を表示PDF形式でダウンロード (1182K) -
Kazuhiko KUME, Takao SHIMIZU, Yousuke SEYAMA1987 年 101 巻 3 号 p. 653-660
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーMicrosomal sn-glycerol 3-phosphate acyltransferase from the guinea pig Harderian gland was studied. Its specific activity (1.0 nmol/min•mg, with palmitoyl-CoA as a substrate) was almost the same as that of the rat liver microsomal enzyme. The enzyme acted on various types of acyl-CoA, the relative reaction rates being as follows: palmitoyl-CoA, 100 (%); stearoyl-CoA, 30; oleoyl-CoA, 50; linoleoyl-CoA, 40; and arachidonoyl-CoA, 20. When assayed in the presence of 1mM 5, 5' dithiobis- (2-nitrobenzoic acid) (DTNB), the activity on palmitoyl-CoA was inhibited by only 20-30%, whereas those for other acyl-CoAs were completely abolished. The DTNB-resistant activity was inhibited by 0.1mM dihydroxyacetonephosphate and 0.5mM dithiothreitol, whereas the DTNB-sensitive activity was not affected. Furthermore, heat treatment at 50°C for 15min abolished most of the DTNBsensitive activity, but not the DTNB-resistant activity. These results, taken together, suggested that the microsomal fraction of the guinea pig Harderian gland contained at least two types of sn-glycerol 3-phosphate acyltransferase, and that, in contrast to in the case of rat liver microsomes, a DTNB-resistant enzyme that utilized exclusively palmitoyl-CoA was predominant.抄録全体を表示PDF形式でダウンロード (624K) -
Daisaku MUNO, Noriko SUTOH, Takamitsu SEKINE1987 年 101 巻 3 号 p. 661-669
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーWhen DNP-SH1-myosin, selectively dinitrophenylated at SH1 by 1, 2, 4-trinitrobenzene, was irradiated with a high-pressure mercury lamp equipped with a UV cut filter, a new 220-kDa band called the X-band appeared right above the heavy chain band (200 kDa) on SDS-PAGE (Laemmli). The time course of the X-band formation was composed of two phases, the initial one being rapid, and the second slow. Immune reaction experiments using antibodies specific for heavy or light chains indicated that the X-band in the initial phase contained heavy chain alone, but no light chains. Such an extra band (106 kDa) was also observed in the initial phase of photolysis of DNP-SH1-Subfragment-1 (heavy chain: 96 kDa) obtained from DNP-SH1-myosin. Trypsinolysis of the 106-kDa product generated a 83-kDa band. N-Terminal sequence analysis and the amino acid composition of the band revealed that the X-band is an intraheavy chain cross-linking product between the 20- and the 50-kDa fragments. This presents a striking contrast to the other cross-linking from SH1 using benzophenone-4-iodoacetamide which reacted with the 25-kDa fragment alone (Lu, R. C. et al. (1986) Proc. Natl. Acad. Sci. U. S. 83, 6392-6396). Based upon the result obtained, the spatial arrangement of the three tryptic domains around SH1 is discussed.抄録全体を表示PDF形式でダウンロード (3731K) -
Taro OGISO, Yoshimasa ITO, Masahiro IWAKI, Hidehiko ATAGO1987 年 101 巻 3 号 p. 671-677
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーHuman urokinase (HUK) was purified from commercial product by high performance liquid chromatography on TSK GEL-G3000SW and affinity chromatography on benzamidine-Sepharose 4 B. The purified enzyme was of a high molecular weight form (molecular weight of 53, 000). This preparation was utilized as an antigen to immunize rabbits; the obtained antibody showed a high specificity against HUK. The antibody was conjugated to CNBr-activated paper disks. The antibody-conjugated paper disk and a fluorogenic peptide substrate, glutaryl-Gly-Arg-4-methyl-coumarine-7-amide, were used to measure urokinase (UK) activity in plasma. The calibration curve obtained by the proposed method passed through the origin and was linear in the range of 0-0.16 IU of HUK. The incubation of HUK with an excess amount of α2-macroglobulin at 37°C for 3h gave only about a 30% decrease of the activity assayed by the proposed method. After incubations of HUK with α1 antitrypsin and antithrombin III, the activity was completely inhibited. The incubation of HUK with plasma at 37°C decreased the activity as a function of time. However, when the antibody-conjugated paper disk was used for the immunoreaction to HUK in plasma at 4°C, no decrease of UK activity was observed. The plasma decay curve of UK activity after a single intravenous (i. v.) injection of HUK into a rabbit (12, 000 IU/kg) indicated bi-exponential kinetics by using this assay method. The rate constants of the α and β phases were 0.120±0.020 and 0.021±0.002min-1, respectively. These result suggest that the proposed method is useful for measuring UK activity in plasma of patients with intravascular coagulation after i.v. administration of UK.抄録全体を表示PDF形式でダウンロード (518K) -
Satoshi FUJII, Hideaki KAWAGUCHI, Hisakazu YASUDA1987 年 101 巻 3 号 p. 679-684
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーWe have identified a 56-kDa fatty acid binding protein in rat renal basolateral membrane and purified it by extraction in nonionic detergent (Triton X-100), followed by gel filtration, DEAE-cellulose chromatography, and affinity chromatography. The purified protein was homogeneous on polyacrylamide gel electrophoresis in the presence of Triton X-100 or SDS. It showed amphiphilic properties on gel filtration, polyacrylamide gel electrophoresis, and oleate-Sepharose 4 B chromatography. Its molecular mass was estimated to be 56 kDa by SDS-polyacrylamide gel electrophoresis. The protein showed optimal binding activity at pH 7.5 and 37°C. The apparent Kd for palmitic acid was 0.79 μM. It was immunologically clearly distinct from renal cytosolic fatty acid binding protein.抄録全体を表示PDF形式でダウンロード (401K) -
Masato HOSHINO, Hideharu TAIRA, Seisuke HATTORI, Masao KAWAKITA1987 年 101 巻 3 号 p. 685-694
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーTreatment of mouse L 929 cells with mouse interferon (IFN) lowered the yield of vesicular stomatitis virus (VSV) in a dose-dependent manner. Accumulation of viral proteins was severely inhibited in IFN-treated cells, whereas cellular protein synthesis was not, indicating that the virus-induced shutoff of cellular protein synthesis was prevented by IFN. In order to identify the major target of IFN action precisely, the effect of IFN treatment on the synthesis of viral RNAs and proteins at various stages during the course of viral replication was examined. Accumulation of viral RNAs late in infectÍon was inhibited, as was the case with viral proteins, but the synthesis of leader RNA and mRNAs early in infection was not significantly inhibited by treatment with a moderate dose of IFN. On the other hand, viral protein synthesis at an early stage of infection was strongly inhibited by IFN. The results indicate that the major target reaction of antiviral action of IFN against VSV multiplication is the translation of viral mRNA.抄録全体を表示PDF形式でダウンロード (4759K) -
Antonio TSUNESHIGE, Kiyohiro IMAI, Itiro TYUMA1987 年 101 巻 3 号 p. 695-704
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe mode of interaction of human hemoglobin (Hb) with the red cell membrane was investigated with special reference to the effect on oxygen binding properties and Hb-membrane binding constants. Compared to free native Hb, the membranebound native Hb showed a strikingly lowered oxygen affinity and smaller response to organic phosphates such as 2, 3-diphosphoglycerate and inositol hexaphosphate. Similar effects of membrane binding were also observed for intermediately cooperative Hbs such as N-ethylmaleimide-treated Hb (NES-Hb) and iodoacetamidetreated Hb (AA-Hb), but very small effects were observed for non-cooperative Hb, i.e., carboxypeptidase A-treated Hb (des-His-Tyr Hb). The magnitude of the affinity lowering was in the order: NES-Hb>native Hb>AA-Hb_??_ des-His-Tyr Hb. In the presence of inositol hexaphosphate, the three chemically modified Hbs showed an increased oxygen affinity when bound to the red cell membrane, probably due to partial replacement of bound inositol hexaphosphate by membrane. The binding to membrane caused a slight decrease in cooperativity for native Hb, but no distinct change in cooperativity was observed for the three modified Hbs. These results imply:a) the red cell membrane binds to deoxyHb more strongly than to oxyHb; b) the difference in membrane binding affinity between oxyHb and deoxyHb is closely related to the quaternary structure change in the Hb molecule occurring upon oxygenation. The higher affinity of the membrane for deoxyHb than for oxyHb apparently disagrees with the conclusion drawn by earlier investigators. However, the present binding experiments by means of ultrafiltration proved that the red cell membrane actually binds to deoxyHb much more strongly than to oxyHb, validating the present conclusion based on oxygenation experiments. Our results are consistent with those obtained recently by other investigators using a synthetic peptide or the cytoplasmic fragment of red cell membrane band 3.抄録全体を表示PDF形式でダウンロード (776K) -
Natsuyo JURI, Yoko KUBO, Sabu KASAI, Shohei OTANI, Masamichi KUSUNOSE, ...1987 年 101 巻 3 号 p. 705-711
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA synthesis of roseoflavin (RoF) by Streptomyces davawensis from 8-amino- (AF) and 8-methylamino-8-demethyl-D-riboflavin (MAF) was demonstrated. The lines of evidence are:1) the RoF formation was increased by addition of AF or MAF to the culture, 2) [2-14C] RoF was formed by addition of [2-14C] AF or [2-14C] MAF to the culture, and the location of the 14C atom at the 2-position was demonstrated by identifying [14C] urea in the hydrolysate of the RoF, 3) [N-methyl-14C] RoF was formed by addition of [methyl-14C] methionine to the culture containing AF or MAF, and the location of the 14C atom was confirmed by the photochemical conversion of the RoF to MAF, the specific radioactivity of which was about half that of the original RoF, and by localization of the 14C atom in 1, 2-dihydro-6-methyl-7-dimethyl-amino-2-keto-1-ribityl-3-quinoxalinecarboxylic acid (QC), which was formed from the RoF by hydrolysis.抄録全体を表示PDF形式でダウンロード (1980K) -
Shigemi NORIOKA, Tomofumi KUROKAWA, Tokuji IKENAKA1987 年 101 巻 3 号 p. 713-721
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA peanut Bowman-Birk (BBI) type protease inhibitors B-III has two regions, 1 and 2, homologous with each other. Each region contains three S-S loops and a reactive site in its outermost loop. The inhibitor was used to investigate the contribution of the S-S loops of BBI-type inhibitors to their inhibitory activity. Twosteps of Edman degradation of the native inhibitor cleaved loop III (the innermost S-S loop) of region 1 of B-III, and the antichymotryptic activity of the first reactive site decreased to about 1/4 of that of native B-III. A third step of Edman degradation split loop II and the inhibitory activity at that site became extremely low (about 1/200 of the original value). These results suggest that protease inhibitor B-III maintains its active conformation by means of the three S-S loops and that the conformation is markedly changed by the splitting of loop II.抄録全体を表示PDF形式でダウンロード (639K) -
Tomofumi KUROKAWA, Saburo HARA, Shigemi NORIOKA, Tadashi TESHIMA, Toku ...1987 年 101 巻 3 号 p. 723-728
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe contribution of the P1' residue at the first reactive site of peanut protease inhibitor B-III to the inhibition was analyzed by replacement of the P1' Arg(11) with other amino acids (Arg, Ser, Ala, Leu, Phe, Asp) after selective modification of the second reactive site. The Arg derivative had the same trypsin inhibitory activity as the native inhibitor (K1=2×10-9M). The Ser derivative inhibited more weakly (K1=2×10-8M). The Ala and Leu derivatives inhibited trypsin very weakly (K1=2×10-7M and 4×10-7M, respectively), and the Phe and Asp derivatives not at all. These results suggest that the P1' arginine residue is best for inhibitory activity at the first reactive site of B-III, although it has been suggested that a P1' serine residue at the reactive site is best for inhibitory activity of Bowman-Birk type inhibitors.抄録全体を表示PDF形式でダウンロード (436K) -
Masaji MURAKAMI, Seikoh HORIUCHI, Kyoko TAKATA, Yoshimasa MORINO1987 年 101 巻 3 号 p. 729-741
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe interactions of high density lipoprotein (HDL) and acetylated high density lipoprotein (acetyl-HDL) with isolated rat sinusoidal liver cells have been investigated. Cellular binding of 125I-acetyl-HDL at 0°C demonstrated the presence of a specific, saturable membrane-associated receptor. This receptor was affected neither by formaldehyde-treated albumin nor by low density lipoprotein modified either by acetylation or malondialdehyde, ligands known to undergo receptormediated endocytosis by the cells, indicating that the receptor for acetyl-HDL constitutes a distinct class among the scavenger receptors for chemically modified proteins. Parallel binding experiments using 125I-HDL also revealed the presence on these cells of a receptor for unmodified HDL. The ligand specificities of these two receptors were similar to each other except that the acetyl-HDL receptor was sensitive to polyanions such as dextran sulfate and fucoidin. Interaction of HDL with the cells at 37°C was totally different from that of acetyl-HDL. Cellular binding of HDL was not accompanied by subsequent intracellular degradation of its apoprotein moiety, whereas its cholesterol moiety was significantly transferred to the cells. In contrast, acetyl-HDL was endocytosed and underwent lysosomal degradation as a holoparticle. This shift in receptor-recognition from the HDL receptor to the acetyl-HDL receptor was accomplished by acetylation of _??_8% of the total lysine residues of HDL apoprotein. This unique difference in endocytic behavior between HDL and acetyl-HDL suggests a potential link of the HDL receptor to HDL-mediated cholesterol transfer in sinusoidal liver cells.抄録全体を表示PDF形式でダウンロード (1156K) -
Akihiko IKEDA, Hideo IWAHASHI, Youichi NEGORO, Ryo KIDO1987 年 101 巻 3 号 p. 743-749
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーRadical species were detected in mixtures of some retinoids with hematin by using the ESR spin-trapping technique. The rates of radical formation were approximately proportÌonal to the oxygen consumptÌon during the incubation of the retinoids with hematin. HPLC analyses of the incubation mixtures of the retinoids with hematin showed that 5, 6-epoxides of the retinoids were formed. The amounts of the epoxides formed were proportional to both oxygen consumption and the amounts of radicals formed. These results suggest that the 5, 6-epoxidations proceed via radical intermediates.抄録全体を表示PDF形式でダウンロード (488K) -
Shyh-Horng CHIOU, Wen-Chang CHANG, Fu-Ming PAN, Tschining CHANG, Tung- ...1987 年 101 巻 3 号 p. 751-759
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーLens crystalline were isolated from the homogenate of carp (Cyprinus carpio) eye lenses by gel permeation chromatography and characterized by gel electrophoresis, immunodiffusion, amino acid analysis, circular dichroism, and protein sequence analysis. Three well-defined fractions corresponding to α/β-, β-, and γ-crystallins were obtained in relative weight percentages of 26, 22, and 52%. The native molecular masses of the purified fractions were determined to be 410, 60, and 20 kDa, respectively. The polypeptide compositions as determined by SDS gel electrophoresis revealed the substantial presence of β-crystallin polypeptides in the α-crystallin fraction; this is also evident in the fractionation of amphibian crystallins but is not common in the case of higher classes of vertebrates. The circular dichroism spectra indicate a predominant β-sheet structure in all three fractions, albeit with some contribution of α-helical structure in the γ-crystallin, the amino acid composition of which bears a resemblance to that of squid crystallin. Sequence comparison of carp γ-crystallin with frog and calf γ-crystallins indicates a high degree of homology in their N-terminal segments despite the dissimilarity of amino acid compositions and weak immunological cross-reactivity.抄録全体を表示PDF形式でダウンロード (1945K) -
Nobuyuki YAMASAKI, Nural ABSAR, Gunki FUNATSU1987 年 101 巻 3 号 p. 761-766
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe states of tryptophan residues in castor bean hemagglutinin (CBH) were analyzed by solvent perturbation studies employing ultraviolet difference spectroscopy. Eight out of 22 tryptophan residues in CBH were exposed to ethylene glycol and glycerol, suggesting that the remaining 14 tryptophan residues are buried in the interior of the CBH molecule. The fraction of tryptophan residues accessible to the perturbant decreased with increase in the molecular size of the perturbant, and only 2 tryptophan residues were exposed to polyethylene glycol 600. Upon binding with raffinose, 2 tryptophan residues were shielded from the perturbing effect of the solvent, and binding of lactose reduced the number of tryptophan residues accessible to the perturbant by 1 mol per mol of protein. Binding of galactose, however, did not change the accessibility of tryptophan to the perturbant. On the other hand, the accessibility of tyrosine to the perturbant remained unchanged after binding with raffmose and lactose, suggesting that tyrosine is not directly involved in the saccharide binding of CBH. Based on these results, it is proposed that one tryptophan residue at the saccharide-binding site on each B-chain of CBH lies on the surface of the protein molecule and is located at a subsite which is accessible to a glucopyranoside moiety in the lactose molecule or a glycopyranosyl-fructofuranosyl moiety in the raffinose molecule, whereas such a residue is not present at the galactopyranosiderecognition site.抄録全体を表示PDF形式でダウンロード (464K) -
Koui TAKAHASHI, Oun Hyun KIM, Koji YANO1987 年 101 巻 3 号 p. 767-773
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe reaction mechanism of calcium ion in the postmortem weakening of Z-disks was studied in myofibrils prepared from fresh or stored muscles. The α-actinin content in myofibrils remained almost unchanged within 10 days postmortem, showing very limited proteolysis of myofibrils during postmortem storage of muscles at 10°C. The postmortem weakening of Z-disks was markedly dependent on muscle pH, showing a minimum at pH 6.5. These results agree well with the calcium-induced weakening of Z-disks of freshly isolated myofibrils, indicating that no protease participates in the postmortem weakening of Z-disks. Z-Disks of myofibrils prepared from stored muscles split into halves after treatment with 0.1 N NaOH for 5min. The identical splitting of Z-disks was induced by a calcium ion concentration of 10-4M, which is of the same order of magnitude as that in the sarcoplasm in postmortem muscle. We therefore conclude that the postmortem weakening of Z-disks is non-enzymatically induced by the raised sarcoplasmic calcium ion concentration of 10-4M. Calcium ions probably solubilize the amor-phous cementing material of Z-disks, leaving unchanged the two sets of Z filaments composed of α-actinin.抄録全体を表示PDF形式でダウンロード (1987K) -
Jun HIRABAYASHI, Hiroshi KAWASAKI, Koichi SUZUKI, Ken-ichi KASAI1987 年 101 巻 3 号 p. 775-787
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe complete amino acid sequence of a soluble β-galactoside-binding lectin (subunit MW 14, 500) of chick embryo was determined. The protein consists of 134 amino acids beginning with serine and ending with glutamic acid, and its N-terminal was blocked with acetate. The agreement of the present result with that obtained from nucleotide sequence analysis (Y. Ohyama et al. (1986) Biochem. Biophys. Res. Commun. 134, 51-56) indicates the lack of a cleavable leader sequence. Internal homologies were observed in several regions along the polypeptide chain. The highest homology (55% identity) was found between residues 42-58 and residues 112-128. This suggests that chick 14 kDa lectin may have evolved via several gene duplications.抄録全体を表示PDF形式でダウンロード (1400K) -
Haruo HOMAREDA, Tadashi NOZAKI, Hideo MATSUI1987 年 101 巻 3 号 p. 789-793
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe effects of Na+ and ATP on the K+ binding to Na+, K+-ATPase were investigated by the centrifugation method with radioactive K+ in the absence of Mg2+. In the presence of 10μM43KCl, 0.6 and 10mM Na+ decreased the amount of bound K+ to one-half and zero, respectively. On the other hand, 10μM and 10mM ATP decreased the amount of K+ to 60 and 25-40%, respectively. When the combined effect of ATP and Na+ was tested, 10μM ATP decreased the Na+ concentration giving half-maximal inhibition of the K+ binding to one-third, showing synergistic inhibition by both ligands, though increase in ATP concentration seemed to depress the inhibitory effect of Na+. The synergistic inhibition by ATP and Na+ suggests that the release of K+ from E2K is not completed by the binding of ATP alone but is completed by the binding of Na+ in addition to ATP during the cycle of Na+, K+-dependent ATP-hydrolysis as well as ion-transport.抄録全体を表示PDF形式でダウンロード (382K) -
Toshiya ENDO, Masanao OYA, Nobuo TAMIYA, Tatsuo MIYAZAWA1987 年 101 巻 3 号 p. 795-804
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe molecular properties of phospholipases (PLases) A2 I and A2 III from a sea snake, Laticauda semifasciata, have been characterized by gel-filtration, as well as proton NMR, CD, UV absorption, and fluorescence spectroscopic methods. PLase A2 I exists as a monomer in aqueous solution in the presence or in the absence of Ca2+. The dissociation constants of the Ca2+-enzyme complexes have been determined for the two enzymes. The 270-MHz proton NMR spectra of PLases A2 I and A2 III have been measured, and the aromatic proton resonances of His-21 and His-48 in the active site have been assigned. By analyzing the pH dependence of the chemical shifts of the histidine proton resonances, pKa values have been determined for His-21 and His-48 with and without Ca2+. The conformational transitions have been found to take place at low pH or at high temperature (at_??_65°C). Fluorescence change of PLase A2 I upon addition of substrate analogs suggests that Trp-70 in PLase A2 I is involved in the binding to micellar substrates. The lack of Trp-70 in PLase A2 III is probably related to the low enzymatic activity as compared with that of PLase A2I.抄録全体を表示PDF形式でダウンロード (755K) -
Toshio TAKAGI, Shigenori MAEZAWA, Yutaro HAYASHI1987 年 101 巻 3 号 p. 805-811
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーSubunit molecular weights of the (Na+, K+)-ATPase of canine renal outer medulla were estimated in the presence of sodium dodecyl sulfate (SDS) by the measuring system consisted of components connected in the following sequence: a TSK-gel G3000 SW column, a UV spectrophotometer, a low-angle laser light scattering photometer, and a differential refractometer. Polypeptide molecular weights of the α- and β-subunits were determined to be 117, 900 and 39, 400, respectively. The measurement required the extinction coefficient at 280 nm of the sample polypeptide in addition to the outputs from the three detectors. The extinction coefficients at 280nm of the α- and β-subunits were determined to be 0.931 and 1.41 ml•mg-1•cm-1, respectively by the quantitative amino acid analysis. The above procedure seems to be most appropriate to determine uniquely the composition of subunits molecular weights of an oligomeric membrane protein.抄録全体を表示PDF形式でダウンロード (634K) -
Shigehiro KAMITORI, Ken HIROTSU, Taiichi HIGUCHI, Kiyoshi KONDO, Katsu ...1987 年 101 巻 3 号 p. 813-816
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーThe aspartate aminotransferase of Escherichia coli was overproduced in cells after genetic manipulation, and was crystallized from a polyethylene glycol solution, pH 7.0. The crystals obtained were of good quality and had diffractions extending beyond 2.4 Å. The space group and unit cell dimensions were determined with a precession camera and a four-circle diffractometer to be C2221, and a=157.1 Å, b=85.5 Å, and c=79.7 Å, respectively. Only one protein subunit is contained in an asymmetric unit.抄録全体を表示PDF形式でダウンロード (1232K) -
Akira WADA, Tomoyuki SAKO1987 年 101 巻 3 号 p. 817-820
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーWe determined the partial primary structures of and identified the genes for new basic proteins A and B in Escherichia coli ribosomal 50S subunits, found by means of an improved two-dimensional gel electrophoresis method (1, 2). The sequence up to the 17 th amino acid of protein B was in agreement with that of the X gene in the spc operon. The gene for protein A was searched for in the GenBank data base using the sequence up to the 35 th amino acid, and was found at a locus between infC and rplT. The base sequence indicated that protein A contained 64 amino acids and had a molecular weight of 6, 984. We conclude that proteins A and B are intrinsic ribosomal proteins, and propose calling their genes, rpml and rpmJ, respectively.抄録全体を表示PDF形式でダウンロード (271K) -
Sei-ichi TANUMA, Kohtaro KAWASHIMA, Hiroyoshi ENDO1987 年 101 巻 3 号 p. 821-824
発行日: 1987年
公開日: 2008/11/18
ジャーナル フリーA novel enzymatic activity, i.e., the catalysis of the formation of ADP-ribosylcysteine, was found in the cytosol of human erythrocytes. The NAD: cysteine ADP-ribosyltransferase was partially purified by sequential chromatographic steps on phenylSepharose, phosphocellulose, and Sepharose CL-6B. The enzyme has an apparent molecular weight of 27, 000±3, 000, as determined by gel permeation. The formation of ADP-ribosylcysteine was associated with the stoichiometric release of nicotinamide from NAD. The enzyme was found to be highly specific toward cysteine and cysteine methyl ester as ADP-ribose acceptors. S-Benzoyl-L-cysteine, cystine, histidine, glutamic acid, arginine, arginine methyl ester, and agmatine were ineffective as acceptors for this enzyme.抄録全体を表示PDF形式でダウンロード (317K)
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