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Volume 87, Issue 1
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Kimitsuna WATANABE, Tairo OSHIMA, Kaoru IIJIMA, Ziro YAMAIZUMI, Susumu ...1980 Volume 87 Issue 1 Pages 1-13
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThree species of methionine tRNAs and phenylalanine, tyrosine, and isoleucine tRNAs were purified from an extreme thermophile, Thermus thermophilus HB8. Formylation studies of the three methionine tRNAs and their codon-specific binding activities to ribosomes showed that two of them (named tRNAMetfl and tRNAMetf2) were initiator tRNAs and the other (named tRNAMetm) was a non-initiator.
The tRNAs from T. thermophilus all had melting temperatures of up to ten degrees higher than the corresponding species from E. coli. Most of the species also had slightly higher G+C contents than the corresponding species of E. coli, and each of them contained one mol each of the modified nucleosides, O2'-methylguanosine (Gm), 2-thioribothymidine (s2T), and 1-methyladenosine (m1A). Their high melting temperatures could be explained by their high G+C contents and the presence of the modified nucleosides, especially s2T. Comparison of the melting temperatures of T. thermophilus tRNAMetf2 with those of E. coli tRNAMetf and tRNAMetm at different magnesium concentrations showed that magnesium was also a factor in the thermostability of the thermophile tRNA.View full abstractDownload PDF (784K) -
Yoh SANO1980 Volume 87 Issue 1 Pages 15-21
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSUsing the usual angular light scattering technique, we have measured the concentration de-pendence of reduced scattering intensity of fractionated bovine lens α-crystallin (αA-chain) in the presence of 30mM calcium chloride and 0.1M sodium chloride. The inverse intensity of scattered light at zero angle per unit concentration of α-crystallin has a significant upward curvature with increasing α-crystallin concentration. The third virial coefficient determined from this upward curvature was 1.24×10-3 (mol1/2ml1/2g-1).View full abstractDownload PDF (549K) -
II. Activation of Prekallikrein with Proteinases and Properties of Kallikrein Activated by Bovine Hageman FactorHidenobu TAKAHASHI, Shigeharu NAGASAWA, Tomoji SUZUKI1980 Volume 87 Issue 1 Pages 23-34
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSActivation of bovine plasma prekallikrein was investigated with several proteinases. Highly purified bovine plasma prekallikrein was rapidly activated to kallikrein [EC 3. 4. 21. 8] by bovine activated Hageman factor, trypsin [EC 3. 4. 21. 4] and Pronase P® (proteinases from Streptomyces griseus) and more gradually by papain [EC 3. 4. 22. 2] and ficin [EC 3. 4. 22. 3]. Activation of prekallikrein was also observed with bovine plasmin [EC 3. 4. 21. 7], but not with bovine clotting factors Xa (Stuart factor) [EC 3. 4. 21. 6] and IXa (Christmas factor) or thrombin [EC 3. 4. 21. 5]. Urokinase [EC 3. 4. 99. 26], Reptilase®, collagenase [EC 3. 4. 24. 3], elastase [EC 3. 4. 21. 11], α-chymotrypsin [EC 3. 4. 21. 1], Nagarse® [EC 3. 4. 21. 14], and stem bromelain [EC 3. 4. 224] did not convert prekallikrein to kallikrein.
Plasma kallikrein activated by Hageman factor released kinin rapidly from bovine high molecular weight (HMW) kininogen. However, from bovine low molecular weight (LMW) kininogen, liberation of kinin was extremely slow. The kallikrein activity was inhibited by soybean trypsin inhibitor (SBTI), Trasylol®, diisopropylfluorophosphate (DFP), and N-α-tosyl-L-lysine chloromethylketone (TLCK), but not by egg-white trypsin inhibitor (EWTI), lima bean trypsin inhibitor (LBTI), heparin or hexadimethrine bromide (Polybrene®). The kallikrein formed an enzyme-inhibitor complex with SBTI and Trasylol®, but not with LBTI. Prekallikrein did not react with SBTI.
Prekallikrein consists of a single polypeptide chain of molecular weight about 90, 000, as estimated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Activation of prekallikrein by Hageman factor was found to involve cleavage of the single peptide bond on the disulfide-bridged polypeptide chain, and no change of molecular weight was observed during the activation. The peptide bond cleaved in prekallikrein by the activation was an Arg-X peptide bond on a disulfide-bridged polypeptide chain.View full abstractDownload PDF (2105K) -
Kenzo OHTSUKI, Ei YAMADA, Masataka NAKAMURA, Nakao ISHIDA1980 Volume 87 Issue 1 Pages 35-45
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESScAMP-dependent (designated as enzyme I, about 68, 000 daltons) and cAMP-independent protein kinase (designated as enzyme II, about 45, 000 daltons) have been partially purified from the nuclei of mouse spleen cells. Both kinases phosphorylated calf thymus histones as well as non-histone proteins (NHP) and required Mg2+ (8mM) or Mn2+ (2mM) for maximal activity. NEM (0.5mM), which is an inhibitor of SH-enzymes, inhibited the histone phos-phorylating activity of enzyme II by more than 90%, whereas it inhibited the activity of enzyme I by less than 10%. Moreover, the activity of enzyme II was more sensitive to high temperature than that of enzyme I. Non-histone protein (CM-III protein) served as a more effective substrate for enzyme II than histones; the Km value for CM-III protein was 34.4 μg/ml whereas that for histone H2a (14, 300 daltons) was 155 μg/ml (1.08×10-5 M). CM-III protein phos-phorylation by enzyme II in vitro was greatly stimulated by the addition of dsDNA, but not by single-stranded DNA or bacterial ribosomal RNA. However, the phosphorylation of CM-III protein by enzyme I was less than 50% of that of histones, and there was no stimulatory effect. SDS-gel electrophoresis showed that two distinct NHPs (about 13, 000 and 19, 000 daltons) prepared from calf thymus chromatin were preferentially phosphorylated by enzyme II in vitro in the presence of dsDNA. This finding suggests that these two NHPs may be specific phosphate acceptors of cAMP-independent protein kinase (enzyme II) in the nuclei of mouse spleen cells.View full abstractDownload PDF (738K) -
Crystallization and Properties of D-Erythrulose Reductase from Chicken LiverKihachiro UEHARA, Shigeyasu MANNEN, Saburo HOSOMI, Tomoyuki MIYASHITA1980 Volume 87 Issue 1 Pages 47-55
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSD-Erythrulose reductase from chicken liver has been purified to homogeneity as judged by acrylamide gel electrophoresis and ultracentrifugation. The overall purification of the en-zyme was 164-fold from a crude extract. The enzyme was crystallized from ammonium sulfate solution at pH 7.0 to give hexagonal plates. The molecular weight determined by sedimentation equilibrium analysis was 94, 600 and that by SDS-polyacrylamide gel electro-phoresis was 22, 400, which suggests a tetrameric structure for the native enzyme. The enzyme was found to contain up to 3 molecules of NADP+ per enzyme; this high amount of NADP+ resulted in a higher absorption at 260 nm than at 280 nm. The extinction coefficient of the enzyme at 290 nm was found to be 4.0. The contents of various amino acids were very similar to those of the beef liver enzyme formerly crystallized in our laboratory. The isoelectric point of the enzyme determined by Ampholine isoelectric focusing was pH 6. 43. The enzyme was shown to catalyze the reduction of D-erythrulose to D-threitol with the concomitant oxida-tion of NAD(P)H to NAD(P)+, and was highly specific to D-erythrulose with an apparent Km of 0.38mM. NADH was less effective than NADPH and the Km's for NADH and NADPH were 67 μM and 7.9 μm, respectively. D-Threitol was slightly oxidized by the enzyme with either NADP+ or NAD+ as a cofactor at pH's 7.5 and 9. 0.View full abstractDownload PDF (1815K) -
Masanobu JANADO, Kuniko TAKENAKA, Hiroko NAKAMORI, Yuki YANO1980 Volume 87 Issue 1 Pages 57-62
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSIt was found that internal water of swollen Sephadex gels could dissolve appreciable amounts of water-insoluble dyes, azobenzene (AB) and dimethylaminoazobenzene (DMAB). The solubilities of AB and DMAB increased exponentially with the concentration of dextran chain in swollen Sephadex gels, i.e., plots of solubility (CG) vs. dextran-chain concentration (Cf) were well described by a family of quartic regression curves (CG=kcf4+CO, k and CO being constants). The thermodynamic parameters pertaining to the transfer of the dyes from ex-ternal water to internal water indicate that in water extensively hydrated by gel matrices, “iceberg” formation is markedly hindered and hence the hydrophobic free energy is corre-spondingly reduced, thereby increasing the solubilities of hydrophobic dyes. Since the solu-bilities of the dyes are proportional to the fourth power of the dextran-chain concentration in swollen Sephadex gels, it can be assumed that the dyes are accommodated in cooperatively hydrated water contained in unit cells made up of four dextran chains.View full abstractDownload PDF (397K) -
I. Purification of OM Cytochrome b from Rat Liver Mitochondria and Comparison of Its Molecular Properties with Those of Cytochrome b5Akio ITO1980 Volume 87 Issue 1 Pages 63-71
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA cytochrome b5-like hemoprotein associated with the outer membrane of rat liver mitochondria, OM cytochrome b, was purified to homogeneity after solubilization with trypsin. OM cytochrome b was separated from microsomal cytochrome b5 by hydroxylapatite chromatography, though they were indistinguishable in DEAE-cellulose chromatography and in Sephadex G-75 gel filtration.
The absorption spectra of reduced OM cytochrome b and cytochrome b5 in the visible region at liquid nitrogen temperature showed small but significant differences between them. A clear difference was also detected in amino acid composition, particularly in the contents of basic amino acids and methionine.
Using rabbit antibodies prepared against purified OM cytochrome b and cytochrome b5, immunochemical comparison was also carried out. No immunological cross reaction was observed by Ouchterlony double diffusion in agar gel or in a quantitative immunopre-cipitation test.
It is thus concluded that OM cytochrome b is distinct from microsomal cytochrome b5.View full abstractDownload PDF (1916K) -
II. Contribution of OM Cytochrome b to Rotenone-Insensitive NADH-cytochrome c Reductase ActivityAkio ITO1980 Volume 87 Issue 1 Pages 73-80
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe participation of OM cytochrome b in the rotenone-insensitive NADH-cytochrome c re-ductase activity of rat tissues was investigated in comparison with that of cytochrome b5, by using antibodies against these two cytochromes.
The specificity of each antibody was confirmed by inhibition studies of NADH-cyto-chrome c reductase activities reconstituted from purified cytochromes and NADH-cytochrome b5 reductase.
OM cytochrome b-mediated NADH-cytochrome c reductase activity was found in various tissues including liver, kidney, heart, and brain. The contribution of this activity to the total rotenone-insensitive NADH-cytochrome c reductase activity was high in heart and brain cells. NADH-cytochrome c reductase activity mediated by OM cytochrome b was principally localized in mitochondrial outer membrane. Immunoadsorption studies using antibody-coated polyacrylamide beads showed that significant OM cytochrome b-mediated activity is present in the microsomal membrane, and that cytochrome b5-mediated activity also exists in the mitochondrial outer membrane.View full abstractDownload PDF (624K) -
Takashi OBINATA, Tomoh MASAKI, Hiromi TAKANO1980 Volume 87 Issue 1 Pages 81-88
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe types of myosin light chains in developing fast skeletal muscle of chick embryo were characterized in terms of their mobilities on SDS-polyacrylamide gel electrophoresis and their reactions with antisera against adult fast, slow, or cardiac myosin light chains. Breast and leg muscles of adult chicken mainly contain fast-type myosin, while at early develop-mental stages, these muscles contain four classes of light chain as judged by SDS-polyacryl-amide gel electrophoresis and immunoelectrophoresis; two of these light chains are of the slow and/or cardiac type and the other two are of the fast type. At late developmental stages, fast-type light chains are present in large amounts and slow and/or cardiac light chains exist only in small amounts. It is suggested that the qualitative changes in light chains during embryonic development are coordinated with those in heavy chains reported by Masaki and Yoshizaki (5).View full abstractDownload PDF (3090K) -
Its Application to Purification of Yeast EnzymesTuyosi FUJITA, Yasuo SUZUKI, Jun-iti YAMAUTI, Isamu TAKAGAHARA, Katsum ...1980 Volume 87 Issue 1 Pages 89-100
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. All the water-soluble yeast enzymes tested, which were only partially precipitated at best in the presence of high concentrations of salts such as ammonium sulfate or sodium formate, were adsorbed on a column of cellulose in the presence of the same concentrations of the salts, and the adsorbed enzymes were chromatographically eluted by decreasing the concentration of the salts.
2. Even in the presence of high concentrations of the salts, the adsorbed enzymes were eluted by urea or by “hydroxy-rich” reagents such as sucrose.
3. Under the experimental conditions used, the salt concentrations required for elution of the adsorbed enzymes were lower with cellulose than with DEAE-cellulose, CM-cellulose, or P-cellulose, indicating that ion exchange groups, either cationic or anionic, affected the adsorption, although the ion exchange groups of DEAE-cellulose, CM-cellulose, and P-cellulose were weakly but definitely functional as ion exchangers even in the presence of high concentrations of the salts.
4. The principal attractive force between cellulose and the enzyme was deduced to be due to hydrogen bonding.
5. This hydrogen bond chromatography was applied for the purification of some yeast enzymes.View full abstractDownload PDF (821K) -
Gilbu SOE, Jinpei YAMASHITA1980 Volume 87 Issue 1 Pages 101-110
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. Polynucleotide phosphorylase [polyribonucleotide: orthophosphate nucleotidyltrans-ferase, EC 2. 7. 7. 8] was purified to near homogeneity from the photosynthetic bacterium, Rhodospirillum rubrum. The purified enzyme had a molecular weight of approximately 160, 000, and consisted of two equivalent subunits of approximately 76, 000 daltons. It cata-lyzed the three reactions described below.
2. In the exchange reaction of the β-phosphate of nucleoside diphosphates with P1 by the purified enzyme in the presence of 3.3mM P1, 6.7mM MgCl2, and 0.33mM or 1.0mM nucleotide at pH 8.0 and 20°C, ADP, GDP, and CDP were better substrates than UDP, while IDP and deoxyribonucleoside diphosphates hardly served as substrates. The ADP-P1 exchange activity was significantly inhibited by high concentrations of either ADP or P1.
3. In the polymerization reaction of ribonucleoside diphosphates by the purified enzyme in the presence of 6.7mM nucleotide and 6.7mM MgCl2 at pH 8.0 and 20°C, ADP was the best substrate; the activities relative to that with ADP were 55 % with UDP, 51% with CDP, and 48 % with IDP, while GDP hardly served as a substrate.
4. In the phosphorolysis reaction of polynucleoside diphosphates by the purified enzyme in the presence of 1.0 mM polynucleotide, 6.7mM P1, and 6.7mM MgCl2 at pH 8.0 and 20°C, poly[U] was the best substrate; the activities relative to that with poly[U] were 32% with poly[A], 28% with poly[I], 21% with poly[C], and 2% with yeast RNA, while poly[G] and yeast DNA hardly served as substrates.
5. The three kinds of activities of the purified enzyme described above were stimulated by divalent cations such as Mg2+, Mn2+, Cd2+, and Co2+View full abstractDownload PDF (688K) -
Teruhiro TAKABE, Satsuki NIWA, Hiroshi ISHIKAWA, Masako MIYAKAWA1980 Volume 87 Issue 1 Pages 111-115
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSKinetic studies of the reduction of plastocyanin from spinach chloroplasts by ascorbate were carried out using a stopped flow apparatus. The reduction of spinach plastocyanin by ascor-bate followed first-order kinetics in the reductant with a rate constant k=415M-1•s-1 [20°C, 0.1M NaCI, pH 8.0 (10mM Tris-HCI)]. The second-order rate constants for the reduction of plastocyanin by ascorbate increased dramatically with increasing pH and ionic strength. The cationic micelles of cetyltrimethylammonium bromide also accelerated this electron-transfer reaction. The importance of electrostatic interactions between plastocyanin and ascorbate is discussed in relation to the photosynthetic electron-transport reactions.View full abstractDownload PDF (339K) -
Katsuhide YUTANI, Kyoko OGASAHARA, Minoru SUZUKI, Yoshinobu SUGINO1980 Volume 87 Issue 1 Pages 117-121
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe near-ultraviolet CD spectra of the wild-type tryptophan synthase α-subunit from Etcherichia coli and four mutant proteins, trpA88(Glu49→Tyr), trpA3(Glu49→Val), trpA33 (Glu49→Met), and trpA11(Glu49→Gln), were examined at pH 7.0 and room temperature (20°C), in order to estimate the CD contribution of the tyrosine residue in the wavelength range above 270 nm.
The CD spectrum of the trpA88 protein showed more intense positive bands than those of the other proteins examined, reflecting the contribution of one additional tyrosine residue. The CD spectra of the other mutant proteins, trpA3, trpA33, and trpA11, were considerably different from that of the wild-type protein, even though the substituted amino acid residues at position 49 were not aromatic.
The difference CD spectra of the mutant proteins versus the wild-type protein were analyzed in terms of vibrational transition of a tyrosine residue. The difference CD spectrum of the trpA88 protein versus the wild-type protein had well-resolved bands at 286, 280, 270, and 263 nm and one shoulder at 275 nm. These band positions corresponded to those of the CD spectrum for L-tyrosine derivatives in a non-aqueous solvent at 77°K, suggesting that Tyr 49 of the trpA88 protein was buried in the hydrophobic interior of the molecule.
The difference CD spectra of the trpA3 and the trpA33 proteins (substituted by more hydrophobic residues at position 49) versus the wild-type protein were also similar to the CD spectrum for L-tyrosine derivatives in a non-aqueous solvent, especially as regards the positions of CD bands. These results suggest that one or more of the seven tyrosyl residues in the protein is(are) near position 49 and interacts with the residue at position 49, and that the state of the tyrosine residue(s) is strongly affected by the hydrophobicity of the residue at position 49.View full abstractDownload PDF (385K) -
Shoji TAJIMA, Ryo SATO1980 Volume 87 Issue 1 Pages 123-134
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSCarboxypeptidase Y (CPY) digestion of cytochrome b5 incorporated into single-walled lipo-somes of egg phosphatidylcholine (PC) resulted in the release of 25 amino acid residues from each molecule of the cytochrome and concomitant detachment of the cytochrome from the vesicles. This finding suggests that the COOH-terminus of the incorporated cytochrome is exposed to the outer surface of the liposomal membrane, since the cytochrome-carrying vesicles were shown to be impermeable to macromolecules such as dextran T-40 by isopycnic centrifugation studies. The possibility that CPY had attacked a small amount of free cyto-chrome b5 which was in equilibrium with the liposome-bound cytochrome could be excluded by the finding that transfer of the bound cytochrome to the unbound state was a much slower process than CPY-induced detachment of cytochrome b5. CPY could also attack the COOH-terminus of cytochrome b5 embedded in dipalmitoyl-PC liposomes even below the phase transition temperature of the synthetic phospholipid. Moreover, the tyrosine residue(s) near the COOH-terminus of the PC vesicle-bound cytochrome could be readily iodinated by the action of lactoperoxidase added externally. These observations indicate that the COOH-terminus of the liposome-bound cytochrome, like its heme-containing, hydrophilic domain, is exposed to the outer surface of the vesicular membrane. The cytochrome detached from the vesicles by CPY digestion could neither rebind to the liposomes nor form an oligomeric aggregate, suggesting that CPY had removed all the amino acid residues which are required for the protein to bind to membranes. The mechanism of CPY-induced detachment of cyto-chrome b5 from liposomes and the size of the peptide segment which is directly involved in the interaction of the cytochrome with the lipid bilayer membranes are discussed.View full abstractDownload PDF (968K) -
Masahiko KISHI, Shigeo NAKAJO, Toshiko SHIBAYAMA, Kazuyasu NAKAYA, Yas ...1980 Volume 87 Issue 1 Pages 135-141
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe cell surface structure of AH-66 hepatoma ascites cells was examined by extracting the intact AH-66 cells with urea and analyzing the extracted proteins. When AH-66 cells were suspended in 1M urea, material composed of approximately 90% protein and 10% carbohy-drate was released. The extracted proteins amounted to about 3% of the total cell proteins and were composed of approximately 30 species as analyzed by sodium dodecyl sulfate gel electrophoresis. The major bands had apparent molecular weights of 84, 000 and 50, 000-60, 000 on the gel. In marked contrast to chick embryo fibroblasts, the extracted proteins contained no components stainable with periodic acid-Schiff reagent. Lactoperoxidase-catalyzed iodination of intact AH-66 cells showed that most of the urea-extractable proteins were located on the outer surface of the plasma membranes of AH-66 cells. It was also found that there are two integral proteins exposed on the outer surface of the plasma membranes of AH-66 cells; one is a major glycoprotein (with a molecular weight of 165, 000) and the other is a periodate-Schiff-negative protein with a molecular weight of 130, 000.View full abstractDownload PDF (1161K) -
Eisuke NISHIDA, Hiromichi KUMAGAI1980 Volume 87 Issue 1 Pages 143-151
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSTubulin was purified from unfertilized eggs or embryos of the sea urchin. In vitro assembly of sea urchin tubulin into microtubules (MTs) was highly sensitive to Ca2+ ions. At low ionic strength, the self-assembly was inhibited by 5×10-7M free Ca2+, and MT elongation which was initiated by mixing sea urchin tubulin with Tetrahyinena cilia outer fiber fragments was inhibited by 10-6-10-5M free Ca2+. Increase in the ionic strength of the assembly medium lowered the Ca2+ sensitivity, in contrast to brain MT assembly. Brain microtubule-associated proteins (MAPS), which stimulated the sea urchin MT assembly, lowered the Ca2+ sensitivity.
Calcium-dependent regulator (CDR) protein was purified from unfertilized eggs of the sea urchin by the purification procedures used for brain CDR. The sea urchin CDR associated with brain tubulin in a Ca2+-dependent manner indistinguishable from that of brain CDR when assayed by the ammonium sulfate fractionation method. Moreover, both CDRs had Ca2+-dependent inhibitory effects on brain MT assembly. However, neither porcine brain CDR nor sea urchin CDR showed a Ca2+-dependent inhibitory effect on sea urchin MT assembly. Sea urchin tubulin assembly initiated by brain MAPS was not inhibited by these CDRs with Ca2+, either. These results suggest that CDRs are not species-specific, but that tubulins respond in a highly specific manner.View full abstractDownload PDF (2872K) -
Tsukasa SUGANO, Masakazu SHIOTA, Takashi TANAKA, Yhoichi MIYAMAE, Masa ...1980 Volume 87 Issue 1 Pages 153-166
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe role of the cellular redox state in the hormonal stimulation of gluconeogenesis was studied in hemoglobin-free perfused rat liver, by fluorimetric measurement of the redox states of intra-cellular pyridine nucleotides.
The maximum rate of glucose production from lactate/pyruvate mixture was observed with a lactate/pyruvate ratio of 10/1, which corresponds to the ratio observed in vivo. Increased reduction of pyridine nucleotides on infusion of ethanol or octanoate was associated with an increased production of glucose from pyruvate, whereas glucose production from lactate decreased. Stimulation of gluconeogenesis from lactate by glucagon was affected by the lactate/pyruvate ratio; a decrease of the lactate/pyruvate ratio resulted in a decrease of the efficacy of glucagon. Stimulation by glucagon of glucose production from pyruvate was abolished during octanoate infusion, although it was still observable during ethanol infusion. In contrast to glucagon, the stimulatory effect of norepinephrine on gluconeogenesis was unaffected by the ratio of lactate to pyruvate. Norepinephrine in the presence of octanoate and ethanol still induced stimulation of glucose production from lactate and pyruvate, which was always accompanied by a transient reduction of pyridine nucleotides.
The results demonstrate that the regeneration of NADH in the cytosol is one of the regulatory factors in gluconeogenesis, and that the effects of glucagon and norepinephrine on gluconeogenesis and on the redox state of pyridine nucleotides are not identical.View full abstractDownload PDF (937K) -
Yoh OKAMOTO, Takamitsu SEKINE1980 Volume 87 Issue 1 Pages 167-178
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSConformational changes of the region involving 17K dalton light chain (G2) in gizzard myosin induced by ATP and its analogs were studied by a combination of light chain exchange and fluorescence spectroscopy. The cysteinyl residues of myosin light chain mixture, 20K dalton G1 and 17K dalton G2 chain, were labeled with a fluorescent thiol reagent, N-(1-anilinon-aphthyl-4)maleimide (ANM). Chicken gizzard myosin was incubated with a large excess of the fluorescence labeled exogenous light chains in 2M urea. After removal of urea and unbound light chains, a strong fluorescent band was observed at the position of the 17K dalton light chain (G2) of myosin on SDS PAGE. There was no difference in enzymatic activity and light chain composition between myosins before and after light chain exchange. The emission spectrum of ANM label in 17K dalton light chain in the bound state in myosin showed a fluorescence enhancement and a blue shift on adding ATP but not ADP. The spectral change disappeared after conversion of ATP to ADP. Various nucleoside triphos-phates other than ATP had similar effects on the fluorescence spectrum. The relative effec-tiveness of most nucleotides on the fluorescence spectral change of ANM in the light chain bound in myosin agreed well with that on tryptophan residues in myosin, except in the case of ADP and CTP. These results suggest that 17K dalton light chain of gizzard myosin is closely related to the ATPase site of myosin.View full abstractDownload PDF (891K) -
Tatsuhiko IKEDA, Keiko KIMURA, Takao HAMA, Nanaya TAMAKI1980 Volume 87 Issue 1 Pages 179-185
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSHistidine and its derivatives increased rabbit muscle fructose 1, 6-bisphosphatase activity at neutral pH with positive cooperativity. In the presence of histidine and carnosine the optimum pH shifted from pH 8.0 to 7.4. The cooperative response of the enzyme to AMP and fructose 1, 6-bisphosphate was observed in the presence of the histidine derivatives.
Of a number of divalent cations tested, only Zn2+ was found to be an effective inhibitor of enzyme activity at low concentrations. The kinetic data suggested that Zn2+ acted as inhibitor as well as activator for the enzyme activity; a high affinity binding site was associated with Kl of approximately 0.5 μm Zn2+ and a catalytic site was associated with Km of approxi-mately 10 μm Zn2+. Rabbit muscle fructose 1, 6-bisphosphatase bound 4 equivalents of Zn2+/ mol, presumably I per subunit, in the absence of fructose 1, 6-bisphosphate. Two equivalents of Zn2+/mol bound to the enzyme were readily removed by dialysis or gel filtration in the absence of a chelating agent. The other two equivalents of Zn2+/mol were removed by his-tidine and histidine derivatives of naturally occurring chelators with concomitant increase in activity.View full abstractDownload PDF (456K) -
Kiyohisa UCHIDA, Yasuharu NOMURA, Nozomu TAKEUCHI1980 Volume 87 Issue 1 Pages 187-194
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSEffects of sodium cholate, deoxycholate, chenodeoxycholate, and lithocholate on serum and liver cholesterol levels, bile flow, biliary cholesterol, phospholipids, and bile acids, and fecal sterols and bile acids were examined in Wistar strain male rats fed either an ordinary diet or a 2% cholesterol diet. Cholate and deoxycholate increased serum and liver cholesterol levels, serum pre β-lipoprotein, bile flow, and biliary secretion of cholesterol, phospholipids, and bile acids, but chenodeoxycholate and lithocholate did not. The total amounts of sterols and of bile acids in the feces did not differ between the cholate and the chenodeoxycholate groups. All the bile acids except lithocholate decreased fecal coprostanol when the diet in-cluded cholesterol. Cholate and deoxycholate produced similar bile acid compositions in the bile and feces, as was the case between chenodeoxycholate and lithocholate, though chenodeoxy-cholate slightly increased the amount of muricholic acids, and lithocholate that of hyodeoxy-cholic acid, in the feces. The effects of cholate and deoxycholate are similar to each other but different from that of chenodeoxycholate or lithocholate in rats. Cholate causes marked accumulation of cholesterol in tissues, increased bile flow and biliary lipid secretion but cheno-deoxycholate does not. Cholate is absorbed much more efficiently than chenodeoxycholate.View full abstractDownload PDF (503K) -
Michio NIINOBE, Setsuro FUJII1980 Volume 87 Issue 1 Pages 195-203
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSAminopeptidase and arylamidase from human liver were purified 1, 580- and 1, 130-fold, respec-tively, by ammonium sulfate fractionation, TEAE-cellulose and hydroxylapatite column chro-matographies, and Sephadex G-200 get filtration. The purified preparations appeared to be homogeneous on polyacrylamide gel electrophoresis.
The molecular weights of aminopeptidase and arylamidase were determined to be 280, 000 and 170, 000, respectively, by gel filtration on Sephadex G-200.
Aminopeptidase showed marked specificities for amino acid amides, such as L-leucine-amide, L-phenylalanineamide, and L-methionineamide. On the other hand, arylamidase showed specificities for amino acid β-naphthylamides, such as L-alanyl-β-naphthylamide and L-leucyl-, β-naphthylamide, but it also hydrolyzed amino acid amides to a considerable extent.
Immunological studies using antibodies to purified aminopeptidase and arylamidase showed that the antigenicities of these two enzymes were different.
Neuraminidase treatment of the purified arylamidase changed its isoelectric point from 3.25 to 4. 95. Various properties (Km values, optimum pH, substrate specificities, and anti-genicity) of the arylamidase were not changed by neuraminidase treatment, but the enzyme became thermo-labile.View full abstractDownload PDF (1190K) -
Susumu OKUMURA, Mieko IWAI, Yoshio TSUJISAKA1980 Volume 87 Issue 1 Pages 205-211
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA lipolytic enzyme which hydrolyzed monoacylglycerols more easily than triacylglycerols was found in the culture broth of Penicillium cyclopium M1. The enzyme was purified to homogeneity and its properties were investigated. Among various substrates used, mono-acylglycerols, especially those of medium chain fatty acids, were hydrolyzed very rapidly. Although the rate was low, the enzyme hydrolyzed methyl esters of fatty acids, Span or tri-acylglycerols of medium chain fatty acids. Based on its substrate specificity, the enzyme was regarded as a partial glyceride hydrolase.
When the partial glyceride hydrolase was used in conjunction with lipase on triacyl-glycerol, the degree of hydrolysis of triacylglycerol became extremely high.View full abstractDownload PDF (1329K) -
III. Effect of Ca2+ on the Reactivity of Two SH Groups of DTNB Light Chain in Myosin and in the Isolated StateKeiichi YAMAMOTO, Reiko HONJO, Takamitsu SEKINE1980 Volume 87 Issue 1 Pages 213-217
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSWe studied the effect of Ca2+ on the reactivities of two SH groups of DTNB light chain (Cys 128 and Cys 157) using a fluorogenic thiol reagent. It was found that a Ca2+-induced change in reactivity occurred only with Cys 128 when the light chain was in an isolated state, whereas it occurred with both Cys 128 and Cys 157 when the light chain was incorporated in myosin. These results indicate that the Ca2+-induced change in the conformation of DTNB light chain in the isolated state was different from that of the light chain in myosin. It may therefore be difficult to relate the Ca2+-induced conformational change observed in the isolated DTNB light chain to the molecular mechanism of myosin-linked Ca2+ regulation.View full abstractDownload PDF (360K) -
Keiichi YAMAMOTO, Takamitsu SEKINE1980 Volume 87 Issue 1 Pages 219-226
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSTo elucidate the substructure of myosin subfragment-1, we digested it with trypsin and papain and determined the sites of its heavy chain and light chains which were readily attacked by these proteolytic enzymes. It was found that a region separated from the N-terminal by about 96K was easily attacked by trypsin, chymotrypsin, and papain. Since the specificities of these enzymes are quite different, the region may have a special structure, and it seems to be located at the flexible hinge between subfragment-1 and the rod. A close relation between the susceptibility of the region and the presence of DTNB light chain was found. The result suggests that some portion of the DTNB light chain is associated with subfragment-1 at this region. Another region separated from the N-terminal by about 26K was found to be attacked readily by trypsin and papain. Since papain has a broad specificity, the region also seems to have some special structure which allows easy access of the enzyme. Alkali light chain 1 was degraded to a roughly 23K fragment by both papain and trypsin, whereas alkali light chain 2 was resistant to these enzymes. The results indicate that the sites attacked by papain and trypsin were located in the N-terminal extra peptide of alkali light chain 1. When DTNB light chain was degraded to a roughly 17K fragment by trypsin, Cys 157 was not dissociated from the DTNB light chain. This means that trypsin did not attack Lys 154 of the light chain. It is suggested, therefore, that trypsin attacked both Arg 7 and Lys 166 when it pro-duced the 17K fragment.View full abstractDownload PDF (3089K) -
Gene Duplication and SpeciationSadao WAKABAYASHI, Toshiharu HASE, Keishiro WADA, Hiroshi MATSUBARA, K ...1980 Volume 87 Issue 1 Pages 227-236
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe amino acid sequences of two ferredoxins from Phytolacca esculenta were determined by a combination of solid-phase sequencing and the conventional methods. Ferredoxins I and II were composed of 96 and 98 amino acid residues, respectively, and ferredoxin I showed sequence heterogeneity at two positions. The amino acid sequences of ferredoxins I and II from Phytolacca esculenta were very similar to those of corresponding ferredoxins I and II from Phytolacca americana. Amino acid differences among Phytolacca ferredoxins and other higher plant ferredoxins suggest that duplication of the ferredoxin gene occurred after the divergence of Phytolacca from other higher plants and preceded the separation of two species of Phytolacca.View full abstractDownload PDF (652K) -
Kenji YAMAMOTO, Yukio IKEHARA, Satoshi KAWAMOTO, Keitaro KATO1980 Volume 87 Issue 1 Pages 237-248
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA simple method for the preparation of lysosomes from livers of rats injected with Triton WR 1339 was developed. Enzymic characterization showed that the Triton WR 1339-filled lysosome (tritosome) preparation isolated by this procedure was almost completely free from mitochondria, peroxisomes, and microsomes. With this method, tritosomes were purified about 50 times with a yield of 8 %. The tritosomal membrane fraction was prepared by osmotic disruption of the purified tritosomes followed by washing with 1M NaCI. Analysis by SDS-polyacrylamide gel electrophoresis showed that tritosomal membrane proteins were distinct from those of plasma membranes. The major glycoproteins found in tritosomal membranes in the higher molecular weight region were not detected in plasma membranes.
When livers were labeled with L-[3H]leucine or D-[3H]glucosamine, the incorporation of both isotopes into tritosomes attained the maximum value at around 3h after the isotope injection. Radioactivities associated with the tritosomal membranes decayed slower than those of the tritosomal contents. SDS-polyacrylamide gel electrophoresis of the membranes labeled with the isotopes for various times demonstrated the distribution and variation with time of radioactivity in the protein and glycoprotein components. The results indicate that the turnover rate of the protein and glycoprotein components in the tritosomal membrane is heterogeneous.View full abstractDownload PDF (1117K) -
Eigo MORI, Yuhei MORITA1980 Volume 87 Issue 1 Pages 249-266
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe amino acid sequence of cytochrome c purified from rice, Oryza sativa L., was determined. The complete amino acid sequence of rice cytochrome c is as follows: Ac-_??_-Ser-Phe-Ser-Glu-Ala-Pro-Pro-G_??_-Asn-Pro-Lys-Ala-Gly-Glu-Lys-Ile-P_??_-Lys-Thr-Lys-Cys-Ala-Glx-Cys-His-Thr-V_??_-Asp-Lys-Gly-Ala-Gly-His-Lys-Glx-Gly-P_??_-Asx-Leu-Asx-Gly-Leu-Phe-Gly-Arg-Glx-S_??_-Gly-Thr-Thr-Pro-Gly-Tyr-Ser-Tyr-Ser-T_??_-Ala-Asp-Lys-Asn-Met-Ala-Val-Ile-Trp-G_??_-Glx-Asx-Thr-Leu-Tyr-Asp-Tyr-Leu-Leu-A_??_-Pro-TML-Lys-Tyr-Ile-Pro-Gly-Thr-Lys-M_??_-Val-Phe-Pro-Gly-Leu-TML-Lys-Pro-Glx-G_??_-Arg-Ala-Asp-Leu-Ile-Ser-Tyr-Leu-Lys-_??_lu-Ala-Thr-Ser (Ac=acetyl group, TML=ε-N-trimethyllysine). The primary structure of rice cyto-chrome c was found to be homologous with those of other plant cytochromes c reported so far; it possesses general features common to plant cytochromes c, and all the invariant residues characterized, in dicotyledonous cytochromes c are also conserved in the sequence of rice cytochrome c, as well as those of other monocotyledonous cytochromes c. The distinctive features of rice cytochrome c are a high content of proline residues, their unique locations in the sequence and the presence of a serine residue at position 96.View full abstractDownload PDF (1024K) -
Ryuken KII, Kuniyasu SAKAI, Akira SANO, Kazuyoshi YONEZAWA, Eikichi HA ...1980 Volume 87 Issue 1 Pages 267-271
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSGuanyl-5'-yl imidodiphosphate (Gpp(NH)p), a nucleotide phosphohydrolase-resistant analog of GTP, caused inhibitory and stimulatory effects on the basal adenylate cyclase activity of rat synaptosomal fractions when manganese was present in the assay mixture, whereas the nucleotide caused only a stimulatory effect when magnesium was employed. In the presence of manganese, the inhibitory and stimulatory effects of Gpp(NH)p could be seen at around concentrations of 10-7M and 10-4M Gpp(NH)p, respectively. The inhibitory and stimulatory effects of Gpp(NH)p were both antagonized competitively by GTP; these effects of the analog were the opposite of those observed with GTP, which was stimulatory and inhibitory for fat cell adenylate cyclase at 10-7M and 10-4M, respectively (Yamamura, H., Lad, P. M., and Rodbell, M. (1977) J. Biol. Chem. 252, 7964-7966). The degree of inhibition by Gpp(NH)p did not depend on the concentration of manganese nor on the addition of ethylene glycol bis(β-aminoethyl ether)-N, N, N', N'-tetraacetic acid.View full abstractDownload PDF (366K) -
Masatake OHNISHI, Takumi KAWAGISHI, Toshiko ABE, Keitaro HIROMI1980 Volume 87 Issue 1 Pages 273-279
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe aim of this work was to study the selective modification of tryptophan residues with NBS. To accomplish this, a specific method to determine tryptophan was required initially. NBS reacts with both tryptophan and tyrosine residues, which are found in most enzyme proteins, and static spectrophotometric observation, which is usually employed to follow the progress of modification, is not selective for tryptophan. However, discrimination of tryptophan from tyrosine was achieved by the kinetic method with a stopped-flow apparatus. The rate of modification of tryptophan residues is 103 times larger than that of tyrosine, so rapid stop-ping of the reaction of NBS brings about the selective modification of tryptophan residues.
Using fluorescence-spectrophotometric and kinetic methods, the modification with NBS of model compounds of the tryptophan residue could be simply followed as a single phase, even though the reaction is complex when followed by the static spectrophotometric method.View full abstractDownload PDF (471K) -
The π-Electronic Structure of 8-Amino-8-Demethyl-D-RiboflavinKiyoshi SHIGA, Yasuzo NISHINA, Iwao OHMINE, Kihachiro HORIIKE, Sabu KA ...1980 Volume 87 Issue 1 Pages 281-287
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe absorption, CD and MCD spectra of 8-amino-8-demethyl-D-riboflavin, which showed novel spectral properties, were measured in the spectral region from 220 nm to 540 nm and the spectra obtained were analyzed in terms of Gaussian wave number curves (from band I to band X).
Semi-empirical calculations of the Pariser-Parr-Pople Hamiltonian were performed to investigate the novel spectral properties and the reactivity at the 5-position.
The theoretical results as well as the experimental results showed that the novel spectral properties were a result of amino substitution at the 8-position.View full abstractDownload PDF (401K) -
Lateef Oriola EMIOLA1980 Volume 87 Issue 1 Pages 289-295
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSα-Amylase from germinating tubers of a yam Dioscorea dumetorum was extracted and purified by four steps of purification. A total yield of 23.1% was obtained with over 1, 600-fold increase in specific activity.
Three distinct amylolytically active protein forms were resolved upon treatment of the preparation on DEAE-cellulose ion exchange chromatography at pH 8.3. All the partially purified α-amylase fractions have similar physical properties with respect to pH optimum, Km values, molecular weights, and energies of activation.
Qualitative paper chromatographic analysis of the α-amylase-amylose digest revealed variable product specificity for the three α-amylase fractions. One form exhibited a dual product specificity for the formation of maltose and maltohexaose, while another form produced exclusively maltopentaose from polysaccharide substrates. The third amylase fraction showed usual action pattern characteristic of most α-amylases.View full abstractDownload PDF (1778K) -
Toshio TANAKA, Susumu OI, Takehiko YAMAMOTO1980 Volume 87 Issue 1 Pages 297-303
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe levan synthesized by Bacillus subtilis levansucrase in the presence of alcohols was of only high molecular weight, while in solutions of high ionic strength only low molecular weight (MW) levan was produced. The addition of low MW levan to the enzyme reaction mixture at low ionic strength stimulated synthesis of a high MW levan, but the levan added was not incorporated into this high MW levan.
Methylation analysis revealed that low MW levans contained glucose, which was isolated as 2, 3, 4, 6-tetra-O-methyl alditol acetate, showing that the glucose units existed as terminal residues. The molecular weight of levan estimated on the basis of glucose content coincided with that determined by the gel filtration method. Methylation analysis also revealed that the number of fructose residues of the linear fraction linked by→6(F)2→ type bonds was 22 for levan with a molecular weight of (8.4-22)×103, while it was 11 for that of 2, 000×103. The number of →6→1(F)2 type branched residues increased with increase in the molecular weight of the levan synthesized.View full abstractDownload PDF (420K) -
Kunio TAKISHIMA, Hiroshi SHIMIZU, Morio SETAKA, Takao KWAN1980 Volume 87 Issue 1 Pages 305-312
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe effects of caffeine, thymol, and procaine on calcium release from fragmented sarcoplasmic reticulum (FSR) from rabbit skeletal white muscle were investigated by the spin label method at the organellar level. Two thiol-directed spin labels, 4-maleimide-2, 2, 6, 6-tetramethyl-piperidinooxyl and 4-(2-iodoacetamide)-2, 2, 6, 6-tetramethylpiperidinooxyl, were used for the labeling of SR proteins. The ratio (W/S) of the weakly (W) and strongly (S) immobilized ESR signals was measured for the maleimide and iodoacetamide labeled FSR. The two labels gave different W/S values, which means that the two labels report conformational changes at different loci of SR proteins. The dependences of the W/S ratios on the concentration of the drugs showed that conformational changes of SR proteins induced by these drugs are not the same. From measurements of the distribution of 5-doxyldecanoic acid methylester between the lipid and water phases, it was found that the conformational changes of the SR proteins caused by thymol or procaine induced a disorder in local regions of the phospholipid bilayers of FSR, while such disordering was not induced by caffeine. On the other hand, caffeine and thymol showed definite effects on calcium release from FSR, while procaine did not. These results indicate that the effects of the drugs on the protein conformations can be well characterized at the organellar level by means of the spin label technique and that some specific changes in the conformations of SR proteins are necessary for calcium release from FSR.View full abstractDownload PDF (570K) -
Yuji ISHIKAWA, Hiroshi YOSHIDA, Nobuo TAMIYA1980 Volume 87 Issue 1 Pages 313-321
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe electric organ of Narke japonica was found to contain 0.4-1.11 nmol of [3H]jtoxin α (Naja nigricollis) binding sites per gram tissue. The nicotinic acetylcholine receptor protein from the electric organ of the Japanese electric ray was purified about 80-fold with an overall yield of 19% from the whole homogenate of the electric organs. The purification procedure included the following procedures: (1) preparation of membrane fragments from the electric organs and solubilization of the receptor from them with a nonionic detergent; (2) DEAE-cellulose chromatography of the solubilized receptor; and (3) affinity chromatography of the DEAE-cellulose fraction using a weak snake neurotoxin, Laticauda semifasciata III (Laticauda semifasciata), as an affinity ligand. The reversibility of the receptor-toxin binding permitted elution of the receptor under mild conditions. The specific toxin binding activity of the final preparation was 2.17 nmol/mg protein. The preparation showed no acetylcholinesterase activity. The preparation gave single coinciding major bands of protein and toxin binding activity upon polyacrylamide gel disc electrophoresis. Upon gel electrophoresis in the presence of sodium dodecyl sulfate, two major bands corresponding to molecular weights of 33, 000 and 43, 000, and two minor bands of 38, 000 and 51, 000 were detected. The toxin binding by purified receptor protein was inhibited to various extents by cholinergic agonists and antagonists. The purified receptor protein was found to contain carbohydrate (18%).View full abstractDownload PDF (630K) -
Izumi OHKAWA, Sawako SHIGA, Makoto KAGEYAMA1980 Volume 87 Issue 1 Pages 323-331
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe iron concentration in the growth medium was found to affect the susceptibility of Pseudomonas aeruginosa PML1550 to pyocin S2, a bacteriocin. The efficiency of killing by pyocin S2 was very low when the indicator cells were grown in an iron-rich medium. The capacity of these cells to adsorb pyocin S2 was reduced. Cultivation under limitation of iron (1 μM or less) was necessary to produce a fully sensitive cell population. The growth under iron limitation was accompanied by the appearance of four protein components in the outer membrane of the cells. Nine mutants resistant to pyocin S2 were isolated and their outer membranes were analyzed. They all lacked one component (Fe-b protein) as well as the adsorption capacity for pyocin S2. These findings suggest a possible role of this protein as the receptor for pyocin S2.View full abstractDownload PDF (649K) -
Haruki YAMADA, Yukihiko ARAMAKI, Toshio MIYAZAKI1980 Volume 87 Issue 1 Pages 333-338
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe carbohydrate-binding protein, discoidin, was synthesized from Dictyostelium discoideum NC-4 grown on a Bacto peptone (Difco) containing medium together with bacteria. When the cells were transferred by serial passage to a Proteose peptone (Daigo)-containing medium, the productivity of discoidin was reduced to a negligible amount, but the cells formed aggre-gates, and another protein which binds with Sepharose 4B was detected by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate.
We conclude that discoidin synthesis is already regulated during growth, and even when the amount of this protein is nil or negligible, the cells still retain aggregate-forming ability.View full abstractDownload PDF (989K) -
Hideo SUGITA, Shoichi ISHIURA, Koichi SUZUKI, Kazutomo IMAHORI1980 Volume 87 Issue 1 Pages 339-341
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (194K) -
Its Localization in the Myofibril, Especially at the Z-BandShoichi ISHIURA, Hideo SUGITA, Ikuya NONAKA, Kazutomo IMAHORI1980 Volume 87 Issue 1 Pages 343-346
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSCalcium-activated neutral protease (CANP) was demonstrated in myofibrils, especially at the Z-band in chicken glycerinated myofibrils, by an immunofluorescent method. The amount of CANP bound to myofibrils was approximately 4 percent of that contained in the whole muscle homogenate. No immunological difference was recognized between the myofibril-bound CANP and the soluble one when examined by Ouchterlony's immunodiffusion analysis. A possible role of myofibril-bound CANP in the physiological turnover of the myofibrillar pro-teins is discussed.View full abstractDownload PDF (1409K) -
Kuni TAKAHASHI, Mamoru ISEMURA, Teruo ONO, Tokuji IKENAKA1980 Volume 87 Issue 1 Pages 347-350
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPorcine liver cathepsin B, a thiol enzyme, exists in at least three forms. While Form III is a single chain polypeptide, two peptide chains with molecular weights of 25, 000 and 4, 000 are noncovalently bound together in Form I and Form II. The present study showed that amino-terminal sequences of Form III and the 4, 000-dalton peptide isolated from Form II are identical. The 4, 000-dalton peptide contained three cysteine or half-cystine residues, one of which was demonstrated to be essential for the enzyme activity by an incorporation study with [14C] jiodo-acetate. It was also shown that the 4, 000-dalton peptide of the activated enzyme contained one cysteine and one cystine residue.View full abstractDownload PDF (215K) -
Yoshinobu SUGINO, Susumu TSUNASAWA, Katsuhide YUTANI, Kyoko OGASAHARA, ...1980 Volume 87 Issue 1 Pages 351-354
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe trp operon of Escherichia coli cloned in a multicopy plasmid produced an amino-terminally formylated tryptophan synthase α-subunit, as well as the normal deformylated one.View full abstractDownload PDF (853K) -
Takahiro TSUJITA, Hiromichi OKUDA1980 Volume 87 Issue 1 Pages 355-357
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSLipase and esterase in post heparin plasma from patients with various diseases were well correlated, r=0.77. Lipase and esterase hydrolyzed both tri and monoacylglycerol. The chain lengths of fatty acids in esters susceptible to the enzymes became longer by conversion of the substrate from triacylglycerol to monoacylglycerol.View full abstractDownload PDF (178K) -
Formation of Amino Acids from Sugars and Ammonia in a Modified Sea MediumHiroshi YANAGAWA, Yukiko KOBAYASHI, Fujio EGAMI1980 Volume 87 Issue 1 Pages 359-362
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSSugars such as glycolaldehyde, glyceraldehyde, erythrose, ribose, and glucose were heated with ammonia in a modified sea medium. Amino acids such as glycine, alanine, serine, threonine, aspartic acid, and glutamic acid were obtained from the reaction mixture. This provides the basis for a model of the genesis of amino acids in the primeval sea.View full abstractDownload PDF (266K) -
Shigeo KOYASU, Akio FUKUDA, Yoshimi OKADA1980 Volume 87 Issue 1 Pages 363-366
Published: January 01, 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe proteins that specifically bind penicillin G were studied with Caulobacter crescentus. This organism possessed at least 5 penicillin-binding proteins (PBPs): PBP lA (132 K), PBP 1Bs (98 K), PBP 2 (77 K), PBP 3 (64 K), and PBP 4 (50 K). As expected from the unique mor-phology, the C. crescentus PBPs were different from those of other sources in molecular weight and localization: C. crescentus did not possess PBPs of low molecular weight. PBP 4 was found only in the outer membrane, while the other PBPs were present mostly in the inner membrane.View full abstractDownload PDF (1542K) -
1980 Volume 87 Issue 1 Pages 367
Published: 1980
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSDownload PDF (17K)
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