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Volume 83, Issue 1
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Studies In Vivo by Intravenous and Intraduodenal Administration, and In Vitro Using Red and Fat CellsFumiyasu SATO, Terufumi ITO, Hiroto AKIYOSHI, Setsuro FUJII1978 Volume 83 Issue 1 Pages 1-7
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe mechanism of incorporation of ATP into fat and red cells of the rat was studied using [8-14C] ATP, [γ-32P] ATP, [8-14C] AMP, and [8-14C] adenosine. ATP was incorporated into these cells after dephosphorylation, but a very small portion of ATP added appeared to cross the cell membranes directly. After entry, dephosphorylated nucleotide was re-utilized for synthesis of ATP.
Furthermore, the in vivo absorption mechanism and distribution of intraduodenally administered ATP and AMP were studied using [8-14C] ATP, [γ-32P] ATP, and [8-14C] AMP. Large amounts of ATP and AMP were dephosphorylated, absorbed into the plasma and incorporated into various tissues, but a very small amount of ATP appeared to cross the intestinal mucous membrane directly. The distribution of radioactive metabolites of ATP in plasma and tissues differed from that of AMP. A considerable amount of ATP was detected in almost all tissues upon administration of ATP, whereas no ATP was detected upon administration of AMP, except in the kidney and liver. The results of analysis of radioactive metabolites of these two nucleotides in portal plasma showed that 40% of total radioactivity in the plasma was accounted for by AMP with intraduodenal administration of ATP, while intraduodenally administered AMP was degraded very rapidly to uric acid and allantoin, and 9% of total radioactivity was accounted for by AMP.View full abstractDownload PDF (495K) -
One-Electron and Two-Electron Reductions of Acceptors by Xanthine Oxidase and Xanthine DehydrogenaseMasao NAKAMURA, Hideo KUREBAYASHI, Isao YAMAZAKI1978 Volume 83 Issue 1 Pages 9-17
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe percentage of one-electron reduction of p-benzoquinone and oxygen was measured in various reactions of xanthine-oxidizing enzymes using cytochrome c as a scavenger. The mechanism of p-benzoquinone reduction was different in milk xanthine oxidase (pancreatintreated) and chicken liver xanthine dehydrogenase when xanthine was used as an electron donor. Similar differences in the reduction mechanism were observed in the type O and type D forms of the reversibly convertible enzyme prepared by the method of Battelli et al. ((1973) Biochem. J. 131, 191-198). The mechanism changed when xanthine was replaced by NADH. When NADH. was used as the electron donor, no significant difference was observed in the mechanism of p-benzoquinone reduction among the four enzymes.
Sulfhydryl groups were found to play a crucial role in the xanthine-NAD+ reductase activity of the type D enzyme and xanthine dehydrogenase. The reductase activity disappeared upon treatment with pCMB. The reductase activity was sensitive to DTNB in the type D enzyme but not in the xanthine dehydrogenase. The oxidase activity of the type D enzyme was restored by autoxidation of the sulfhydryl groups but not by reaction of the enzyme with DTNB or pCMB. It was concluded that the formation of S-S bond (s) was essential for the oxidase activity and also for the oxidase-type mechanism of p-benzoquinone reduction in the xanthine-p-benzoquinone reactions.View full abstractDownload PDF (595K) -
Sadao MATSUURA, Takashi SUGIMOTO, Chizuko KITAYAMA, Motoo TSUSUE1978 Volume 83 Issue 1 Pages 19-25
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSStructural elucidation of an intensely blue fluorescent compound (A) formed from sepiapterin by Bacillus subtilis is described. The structure of the catabolite (A) was found to be 2-amino-6-(1-carboxyethoxy)-4(3H)-pteridinone (9) from both spectroscopic and degradation studies. This was confirmed by an unambiguous sysnthesis of 9. The stereochemical structure of the side chain at the 6-position of A was confirmed to be the L (or S) configuration, as in sepiapterin, by analysis of the lactic acid formed from A on acid hydrolysis. This suggests that the side chain is rearranged intact during the catabolic conversion of sepiapterin. A possible mechanism for the conversion is discussed.View full abstractDownload PDF (464K) -
Yukihiro SANADA, Nobumasa YASOGAWA, Nobuhiko KATUNUMA1978 Volume 83 Issue 1 Pages 27-33
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe activities of serine protease, cathepsin B1, ornithine aminotransferase, and aldolase in skeletal muscles of mice with hereditary muscular dystrophy and their normal litter mates were studied. In dystrophic muscle, the specific and total activities of serine protease were much higher than in normal muscle, and the specific activities, but not the total activities, of cathepsin B1 and ornithine aminotransferase were twice those in normal muscle. Dystrophic muscle also contained lower specific and total activities of aldolase than normal muscle. Its myofibrillar protein was strikingly different from that of normal muscle, and several new fragments, which are normally formed by limited proteolysis, were found in dystrophic muscle. When myofibrillar proteins of normal and dystrophic muscles were incubated with highly purified serine protease, their myosin, a-actinin and tropomyosin disappeared completely.View full abstractDownload PDF (1677K) -
Satoko ISEMURA, Tokuji IKENAKA1978 Volume 83 Issue 1 Pages 35-48
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe amino acid sequences of fragment I, the N-terminal cyanogen bromide fragment, and fragment II, a fragment between the first and second methionine residues, of rat serum albumin were determined by conventional methods in consideration of the sequences of human and bovine serum albumin. These sequences were compared with those of human and bovine serum albumin.View full abstractDownload PDF (741K) -
IV. Structure around the Sa Thiol GroupTsuneyoshi HORIGOME, Tatsuhisa YAMASHITA1978 Volume 83 Issue 1 Pages 49-56
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe structure of a tryptic peptide containing one specific sulfhydryl group (Sa), which is responsible for the activation of Mg2+-ATPase of myosin B and is present in the light meromyosin region of the myosin molecule, was studied. The amino acid sequence was deduced to be Thr (or Ser)-Asn-Ala-Ala-Cys-Ala-Ala-Leu-Asp-Lys-Lys. In addition, a space-filling model around Sa was built up by comparing Sa-peptide with the amino acid sequence around Cys 190 of α-tropomyosin, and the high reactivity of Sa with N-ethylmaleimide is considered based on this model.View full abstractDownload PDF (1183K) -
Sho TAKAHASHI1978 Volume 83 Issue 1 Pages 57-60
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSSodium borohydride, in place of stannous chloride or titanous chloride, is effective in the preparation of the ninhydrin reagent for automated amino acid analysis. The reagent, coupled with dimethyl sulfoxide as a solvent, afforded a very stable ninhydrin solution which did not form prcecipitates in the flow lines of the analyzer.View full abstractDownload PDF (228K) -
Mitsuhide NOSHIRO, Tsuneo OMURA1978 Volume 83 Issue 1 Pages 61-77
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSRabbit antibodies were prepared against NADPH-cytochrome c reductase, NADH-cytochrome b5 reductase, cytochrome b5, and cytochrome P-450 of rat liver microsomes. The antibodies were purified by adsorption on antigen-conjugated Sepharose, and used in elucidating the pathway of electron transfer from NADH to cytochrome P-450 in the oxidation of drugs catalyzed by mouse liver microsomes. These redox enzymes of rat liver microsomes were immunochemically identical with the corresponding enzymes of mouse liver microsomes as determined by Ouchterlony double diffusion tests and inhibition studies on microsomal reductase activities.
The antibody against NADPH-cytochrome c reductase strongly inhibited all of the NADH-supported drug oxidation reactions examined; these were 7-ethoxycoumarin Odeethylation, benzo(a)pyrene hydroxylation, benzphetamine N-demethylation, and aniline hydroxylation. The antibody against cytochrome b5 inhibited NADH-supported 7-ethoxycoumarin O-deethylase, benzo(a)pyrene hydroxylase, and benzphetamine N-demethylase, but did not inhibit aniline hydroxylase. The antibody against NADH-cytochrome b5 reductase inhibited NADH-supported 7-ethoxycoumarin O-deethylase and benzo(a)pyrene hydroxylase, but did not inhibit benzphetamine N-demethylase or aniline hydroxylase. NADPH- and NADH-supported aniline hydroxylase was not inhibited by the antibody against cytochrome P-450 which had been prepared against phenobarbital-induced cytochrome P-450. However, the other three reactions were inhibited by this antibody.
The participation of NADPH-cytochrome c reductase in NADH-supported drug oxidation reactions was further confirmed by the selective removal of this reductase from microsomes, which was accomplished by mild trypsin digestion. Both NADPH- and NADH-supported oxidations of aniline by trypsin-treated microsomes decreased in parallel with the loss of NADPH-cytochrome c reductase from microsomes. The decrease of 7-ethoxycoumarin O-deethylase activity also almost paralleled that of the reductase activity. The high Km value for NADH and the competitive inhibition by NADP+ of NADH-supported drug oxidation reactions suggested that NADPH-cytochrome c reductase accepts electrons directly from NADH and transfers them to cytochrome P-450.
These inhibition profiles and kinetic evidence confirmed that NADPH-cytochrome c reductase is an essential component in the electron flow from NADH to cytochrome P-450 for drug oxidations, whereas NADH-cytochrome b5 reductase and cytochrome b5 participate in NADH-supported oxidation of some but not all drugs.View full abstractDownload PDF (2036K) -
Hiroshi NAKADA, Ikuo YAMASHINA1978 Volume 83 Issue 1 Pages 79-83
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSTwo types of ascites hepatoma cells, AH 66 and AH 130 FN, were treated with trypsin to observe the release of complex carbohydrates constituting the plasma membranes. From AH 66 cells, mucopolysaccharide (heparan sulfate) was preferentially released. From AH 130 FN cells, N-glycosidic glycopeptides were preferentially released whereas no mucopolysaccharide (chondroitin sulfate A) was released.View full abstractDownload PDF (920K) -
Eisuke HANADA, Shizuo HANDA, Kunio KONNO, Tamio YAMAKAWA1978 Volume 83 Issue 1 Pages 85-90
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe change of the glycolipid pattern in rat granuloma during growth was reported in the previous paper. The main neutral glycolipid in rat granuloma was found to be tetraglycosylceramide similar to globoside I from human erythrocytes and a new glycolipid X was found (J. Biochem. (1977) 81, 1079-1083).
The chemical structures of these glycolipids were studied by analysis of the sugar composition, oxidation with chromium trioxide, mass spectrometry after permethylation, analysis of partially methylated sugars obtained from permethylated glycolipids, and glycosidase treatment. From the results, the chemical structures are proposed as follows:
Tetraglycosylceramide:
GalNAcβ1-3Galα1-3Galβ1-4G1cβ1-1Ceramide
Glycolipid X:
Galα1-3Galβ1-_??_-3Galβ1-4G1cβ1-1Ceramide
The structure of glycolipid X is similar to that of blood group B active glycolipid obtained from human erythrocytes except that N-acetylglucosamine is replaced by N-acetylgalactosamine. Glycolipid X showed blood group B activity as high as B-active glycolipid obtained from human erythrocytes.
The main neutral glycolipid of the macrophage has the same structure as that of glycolipid X as shown by sugar composition, glycosidase treatment and blood group B activity.View full abstractDownload PDF (815K) -
Kiyoshi KONDO, Kozo NARITA, Chen-Yuan LEE1978 Volume 83 Issue 1 Pages 91-99
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSβ1-Bungarotoxin purified from the venom of Bungarus multicinctus (Formosan banded krait) contained no carbohydrate and behaved as a homogeneous protein on polyacrylamide gel electrophoresis at pH 4.1 and SDS-polyacrylamide gel electrophoresis without 2-mercapto-ethanol treatment. Its molecular weight and isoelectric point were estimated to be about 21, 000 by gel filtration and about 9.5 by isoelectric focusing, respectively. The toxin treated with the reducing agent was split into two polypeptide chains as revealed by SDS-polyacrylamide gel electrophoresis and their molecular weights were calculated to be about 13, 000 and 7, 000.
The two polypeptide chains (the large one named the A chain and the small one the B chain) were isolated by gel filtration after reduction of disulfide bonds in the toxin followed by alkylation. The A chain contained 120 amino acid residues including 13 half-cystines and the B chain 60 residues including 7 half-cystines. The two chains were supposed to link by disulfide bond(s) in the intact toxin which contained no free sulfhydryl groups.
The N-terminal residues of the A and B chains were asparagine and arginine and the C-terminal ones were glutamine and proline, respectively, in accordance with the results of the terminal analyses of the intact toxin.View full abstractDownload PDF (1929K) -
Kiyoshi KONDO, Kozo NARITA, Chen-Yuan LEE1978 Volume 83 Issue 1 Pages 101-115
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe two dissimilar composite polypeptide chains (A and B) in β1-bungarotoxin were isolated as their reduced and carboxymethylated derivatives as reported in the preceding paper. The N-terminal sequences were determined with a sequenator up to the 39th residue for the RCM-A chain and up to the 25th residue for the RCM-B chain with repetitive yields of 90-95%. The tryptic and chymotryptic peptides from the two chains were isolated and their structures were determined by manual Edman degradation together with dansyl-Edman and carboxypeptidases A and Y. To complete the primary structures of the two chains, information on the tryptic peptides derived from the maleylated derivatives of the two chains was also used.
The completed amino acid sequence of the A chain containing 120 residues (molecular weight, 13, 500) is similar to that of notexin, a presynaptic neurotoxin from Australian tiger snake venom, and phospholipases A from other snake venoms. The amino acid sequence of the 60 residues in the B chain (molecular weight, 7, 000) bears no resemblance to any basic polypeptides from snake venoms. The B chain probably plays a significant role by interacting with some components in presynaptic membranes of neuromuscular junctions.View full abstractDownload PDF (1065K) -
II. Orientation of the Vesicles Studied by Localization of EnzymesIchiro YAMATO, Masamitsu FUTAI, Yasuhiro ANRAKU, Yoshiaki NONOMURA1978 Volume 83 Issue 1 Pages 117-128
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSOrientation of cytoplasmic membrane vesicles (IM vesicles) of Escherichia coli K 12 prepared by the method of Yamato, Anraku and Hirosawa ((1975) J. Biochem. 77, 705-718) was studied by determining uptake activities for calcium ion and proline and by estimating localization of certain membrane marker enzymes.
The IM vesicles showed respiration-driven uptake activities of Ca2+ and proline. Calcium ion was taken up by the vesicles with NADH but the NADH-dependent Ca2+ uptake was not inhibited by D-lactate. Effects of NADH oxidation on the active, n-lactate-dependent proline uptake was found to be additive. These findings suggested strongly that orientation of IM vesicles was heterogeneous and that the IM preparation contained right-side out and inverted vesicles but no mosaic vesicles.
About 60% of the D-lactate and glycerol-3-phosphate oxidase activities were inhibited by the antibody against D-lactate dehydrogenase [EC 1. 1. 1. 28] and ferricyanide, respectively. About 70% of the glycerol-3-phosphate-ferricyanide reductase was detectable without toluenization. D-Lactate- and glycerol-3-phosphate-dependent proline uptakes were inhibited by 40%, by the antibody and ferricyanide, respectively. From these data and the available criteria for orientation, the populations of IM vesicles with different orientations were estimated: 70% of the total population were right-side out closed vesicles and 30% were inverted vesicles or unsealed membrane fragments. In addition, about 40% of the D-lactate dehydrogenase of the right-side out closed vesicles was suggested to be dislocated from the original location and found on the outside.View full abstractDownload PDF (2446K) -
Hirofumi ONISHI, Yoosuke YAMADA, Mitsuo IKEBE, Hiroshi SUZUKI, Shizuo ...1978 Volume 83 Issue 1 Pages 129-135
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSOn studying the steady-state activity in 0.6M KCl, it was found that Mg-ATPase of chicken gizzard myosin was identical with that of rabbit skeletal myosin in the pH-activity profile, Michaelis-Menten constant, and maximum velocity. As regards the “initial burst” of ATP splitting in the presence of Mg (0.6M KCl), it was found that gizzard and skeletal myosins were identical both in the size of the initial burst and in the velocity-ATP concentration relationship. The only difference we observed was that the Ca- and EDTA-ATPase activities of gizzard myosin were, as reported by other investigators, approximately one-half to one-third of those of skeletal myosin, although the pH-activity profile for the ATPase of gizzard myosin was essentially the same as that of skeletal myosin.View full abstractDownload PDF (489K) -
Shigeyuki ICHIHARA, Shoji MIZUSHIMA1978 Volume 83 Issue 1 Pages 137-140
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSEscherichia coli incorporates iron as a complex with enterochelin. By using mutants which lack one or the other, or both, of the outer membrane proteins, O-2b and O-3, we have shown that protein O-2b (feuB protein) is responsible for the primary binding of the iron-enterochelin complex to the outer membrane in the process of iron transport.View full abstractDownload PDF (231K) -
Concentration Method and CharacterizationHiroyuki SUMI, Naotika TOKI, Yumiko TAKADA, Akikazu TAKADA1978 Volume 83 Issue 1 Pages 141-147
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSUrinary enzymes and inhibitors were concentrated by using several methods, such as membrane filter, polyethyleneglycol, ion exchange, bentonite, celite, silica gel, and Arg-Sepharose columns. Of these methods, Arg-Sepharose adsorption was shown to be the most suitable for the concentration method. One liter of normal human urine concentrated by Arg-Sepharose column contained not only esterase activities on Na-acetylglycyl-L-lysine methyl ester (AGLMe); 9.15, p-tosyl-L-arginine methyl ester (TAMe); 3.00, N-acetyl-L-arginine methyl ester (AAMe); 2.33, Na-benzoyl-L-arginine ethyl ester (BAEe); 2.01, p-tosyl-L-lysine methyl ester (TLMe); 1.47, and N-acetyl-L-tyrosine ethyl ester (ATEe); 0.55 μmol/min, but also very strong anti-tryp-sin activity (inhibiting 5, 049 μg of trypsin).
The AGLMe hydrolyzing enzyme showed two peaks with molecular weights of 54, 000 and above 100, 000 on using gel filtration on Sephadex G-200, both of which had plasminogenactivating activity and were completely neutralized by anti-urokinase antiserum, and were thought to be urokinase. The TAMe hydrolyzing enzyme was thought to be kallikrein, which corresponded to a molecular weight of 43, 000 and had strong kinin-producing activity. Urinary trypsin inhibitor showed a molecular weight of 67, 000 and migrated to the serum prealbumin fraction on Pevikon block electrophoresis at pH 8.6.
From the substrate spectrum and the enzyme recovery of the urine concentrate the possibility of the presence of some other new urinary enzymes and inhibitors was also suggested.View full abstractDownload PDF (1141K) -
II. The Contributions of Hyaluronidase, β-Glucuronidase, Sulfatase, and β-N-Acetylhexosaminidase in the Case of Chondroitin 4-SulfateShiro HAYASHI1978 Volume 83 Issue 1 Pages 149-157
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSChondroitin 4-sulfate and chondroitin were digested with lysosomes under acidic conditions. The contributions of hyaluronidase [EC 3. 2. 1. 35], β-glucuronidase [EC 3. 2. 1. 31], β-N-acetyl-hexosaminidase [EC 3. 2. 1. 52], and sulfatase [EC 3. 1. 6. 4] to the degradation of chondroitin 4-sulfate were examined on the basis of characterization and identification of the digestion products.
Chondroitin 4-sulfate was first degraded only by hyaluronidase, and sulfatase did not significantly contribute to the initial degradation of polymeric chondroitin 4-sulfate. In further degradation, the main oligosaccharides produced were normally sulfated odd-numbered oligosaccharides such as tri-, penta-, hepta-, and nonasaccharides. In contrast to the results of digestion studies of hyaluronic acid, octa- and decasaccharides of chondroitin 4-sulfate were not digested by hyaluronidase, but by the concerted action of exoglycosidases and sulfatase. It is concluded that the dodecasaccharide derived from chondroitin 4-sulfate serves as the lowest-molecular-weight substrate for hyaluronidase and the decasaccharide as the largest-size substrate for β-glucuronidase in the degradation of chondroitin 4-sulfate by the enzymes of lysosomes.
The degradation of chondroitin by the lysosomes occurred in a similar way. Therefore the difference in the pathways of degradation between hyaluronic acid and chondroitin 4-sulfate may be attributed to their hexosamine compositions. β-Glucuronidase cleaves glucuronic acid in the terminal nonreducing position of even-numbered oligosaccharides which are derived from chondroitin 4-sulfate regardless of the presence of the sulfate residue on the adjacent N-acetylgalactosamine. The sulfated odd-numbered oligosaccharides were resistant to β-N-acetylhexosaminidase. The affinity of β-N-acetylhexosaminidase for the odd-numbered oligosaccharides from chondroitin was lower than that of β-glucuronidase for the evennumbered oligosaccharides. No contribution of sulfatase, which cleaves the sulfate residue of N-acetylgalactosamine at the nonreducing end, was found.View full abstractDownload PDF (1186K) -
Seiki KURAMITSU, Setsuo KURIHARA, Kiyoshi IKEDA, Kozo HAMAGUCHI1978 Volume 83 Issue 1 Pages 159-170
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSFluorescence spectra of hen egg-white, turkey egg-white, and human urine lysozymes [EC 3. 2. 1. 17] were measured at various pH values by using 305 nm light for the excitation. The pH dependence curves of the fluorescence intensity at the maximum wavelength for these lysozymes were very similar in shape to each other, though the intensities were different. The results of the pH dependence of the fluorescence intensity of two hen lysozyme derivatives, in each of which Asp 52 and Glu 35 had been selectively esterified, and of turkey lysozyme, in which Asp 101 in hen lysozyme is replaced by Gly, showed that only the ionization of Glu 35 and Asp 52 affects the fluorescence of Trp 108 in hen and turkey lysozymes. The pK values of Asp 52 and Glu 35 of hen and turkey lysozymes determined by analyses of the pH dependence of the fluorescence excited at 305 nm in the pH range of 2 to 8 were identical with those determined from the pH dependence of the extinction difference at 301.5 nm (Itani et al. (1975) J. Biochem. 78, 705-711; Kuramitsu et al. (1977) J. Biochem. 82, 585-597) and the circular dichroism at 305 nm (Kuramitsu et al. (1974) J. Biochem. 76, 671-683; (1975) ibid. 77, 291-301). The pH dependence of the fluorescence excited at 305 nm of human lysozyme, in which Trp 62 in hen lysozyme is replaced by Tyr, was also interpreted in terms of the ionization of Asp 52 and Glu 35, with pK values identical with those determined from the pH dependence of the circular dichroism at 305 nm (Kuramitsu et al. (1974) J. Biochem. 76, 671-683) and the extinction difference at 300nm (Kuramitsu et al., to be published.)
The fluorescence spectra of hen, turkey, and human lysozymes excited at 281nm were different from the respective spectra excited at 305nm, and the pH dependence of the fluorescence intensity excited at 281nm could not be completely explained in terms of the ionization of the catalytic groups.
The fluorescences of hen, turkey, and human lysozymes were quenched above pH 8. Comparison of the fluorescence of intact hen lysozyme and that of a lysozyme derivative, in which all the amino groups had been acetylated, showed that an amino group(s) in addition to a tyrosyl residue quenched the tryptophyl fluorescence above pH 8.View full abstractDownload PDF (886K) -
Kazunobu MATSUSHITA, Osao ADACHI, Emiko SHINAGAWA, Minoru AMEYAMA1978 Volume 83 Issue 1 Pages 171-181
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe outer and inner cytoplasmic membranes of Pseudomonas aeruginosa were separated as small and large membranes, respectively, from the cell envelope of this organism treated with lysozyme in Tris-chloride buffer containing sucrose and MgCl2 by differential centrifugation.
The small membrane fraction contained predominantly 2-keto-3-deoxyoctonate (KDO), and little cytochromes or oxidase activities. The small membrane was composed of only 9 polypeptides and showed homogeneous small vesicles electron-microscopically. On the other hand, the large membrane fraction had high cytochrome contents and oxidase activities, and little KDO. The large membrane was composed of a number of polypeptides and showed large fragments or vesicles electron-microscopically. These results indicate that the small and large membranes are the outer and inner cytoplasmic membranes of P. aerauginosa, respectively.
The isolated outer membrane showed a symmetrical protein peak with a density of 1.23 on sucrose density gradient centrifugation and the isolated inner membrane showed an unusually high density, probably due to association with ribosomes and extrinsic or loosely bound proteins. EDTA lowered the density of both membranes and caused lethal damage to the outer membrane, causing disintegration with the release of lipopolysaccharide (LPS), proteins and phospholipid.View full abstractDownload PDF (2127K) -
Masahiro ARIKI, Toshio FUKUI1978 Volume 83 Issue 1 Pages 183-190
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSGlycogen phosphorylase b from rabbit muscle was rapidly inactivated by incubation with 1-cyclohexyl-3-(2-morpholinyl-(4)-ethyl)carbodiimide metho p-toluenesulfonate (CMC) at pH 5.1. The inactivation was pH-dependent and was not restored by treatment with hydroxylamine. The addition of glycine ethyl ester or N-(2, 4-dinitrophenyl)-ethylenediamine (DNP-EDA) markedly increased the rate of inactivation. Of the various amino analogs of glucose tested, only glucosyl amine accelerated the inactivation, although they are all bound to the glucose 1-phosphate site of the enzyme. In the absence of amines, incorporation of about 3 mol of [metho-14C] CMC per protein monomer was observed on complete inactivation. In the presence of DNP-EDA, however, only 2 mol of [metho-14C] CMC and 1 mol of DNP-EDA were incorporated before the activity was completely lost. The treatment of phosphorylase b with CMC did not change the Km values of the enzyme for glucose 1-phosphate and AMP, in spite of the 56Y. inactivation. It is suggested that, in the phosphorylase-catalyzed reaction, an essential carboxyl group of the enzyme plays a role in the protonation of the glucosidic oxygen of glucose 1-phosphate.View full abstractDownload PDF (583K) -
Mayumi KANEKO, Makoto ISHIMOTO1978 Volume 83 Issue 1 Pages 191-200
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSCell extract from a strain of Propionibacterium acidi-propionici with high nitrate reductase (NaR) activity catalyzed nitrate reduction with glycerol phosphate, NADH, or lactate. The reaction was inhibited partially by fumarate or oxygen. NaR linked to methyl viologen was found mostly in particulate fractions. It was solubilized by treatment with Emulgen 810 and purified 46-fold by DEAE-cellulose, Sepharose 4B, and triple DEAE-Sephadex chromatographies in the presence of the detergent. It was rather labile but was stabilized by glycerol. The molecular weight was estimated to be 230, 000 by Sepharose 4B gel filtration and the isoelectric point was pH 5.0-5.5. The pH optimum was at 6.5-7.5 and Km for nitrate was 0.1mM. As electron donors, methyl and benzyl viologen were utilized well but FAD and FMN were fairly ineffective. Chlorate was an active acceptor as well as nitrate. Azide, cyanide, and thiocyanate inhibited NaR. On adding 1mM tungstate to the growing medium, the NaR level in grown cells was lowered; addition of 0.01mM molybdate restored the activity partially. NaR is suggested to be a molybdo-protein, similar to this enzyme from other bacteriaView full abstractDownload PDF (1187K) -
Kiyoaki KITO, Yukihiro SANADA, Nobuhiko KATUNUMA1978 Volume 83 Issue 1 Pages 201-206
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe mechanism of inhibition of ornithine aminotransferase [EC 2. 6. 1. 13] by L-canaline (α-amino-γ-amino-oxybutyric acid) was investigated. Spectral changes of pyridoxal 5'-phosphate in ornithine aminotransferase on addition of L-canaline showed that L-canaline formed an oxime-type compound with pyridoxal 5'-phosphate that had the same spectra as the compound formed on addition of hydroxylamine to the holoenzyme. Kinetic studies indicated that hydroxylamine was a reversible noncompetitive inhibitor, whereas L-canaline was an irreversible inhibitor of ornithine aminotransferase. Other analogs, such as δ-aminovaleric acid and α-N-acetyl-L-ornithine, also reacted with the pyridoxal 5'-phosphate of the enzyme, but these compounds were competitive inhibitors with respect to L-ornithine. L-Canaline and hydroxylamine also reacted with pyridoxal 5'-phosphate in pig heart aspartate aminotransferase [EC 2.6.1.1] to produce an oxime, but both of them were reversible and noncompetitive inhibitors of the enzyme. The K1 value of hydroxylamine for ornithine aminotransferase was 4.3×10-7M and those of L-canaline and hydroxylamine for aspartate aminotransferase were 1.7×10-4M and 2.2×10-5 M, respectively.View full abstractDownload PDF (432K) -
Masahiro YAMAMOTO, Yoshimi TAKAI, Masanori INOUE, Akira KISHIMOTO, Yas ...1978 Volume 83 Issue 1 Pages 207-212
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe protein kinase which is produced from its proenzyme partially purified from rat liverthrough limited proteolysis by a Ca+2-dependent protease (Takai, Y., Yamamoto, M., Inoue, M., Kishimoto, A., & Nishizuka, Y. (1977) Biochein. Biophys. Res. Commun. 77, 542-550) is characterized. The protein kinase is entirely independent of cyclic nucleotides. The enzyme phosphorylates histone and protamine but not casein or phosvitin. The active protein kinase shows an optimum pH of 8.5 to 9.0, and requires high concentrations of Mg2+ (50 to 100mM) and 2-mercaptoethanol (Ka 6mM). The enzyme shows a Stokes radius of about 38Å, and an S value of about 3.9 which corresponds to a molecular weight of 5.1×104. Analysis on the phosphorylated sites in histone fractions indicates that the enzyme phosphorylates Ser-38 in HI histone and Ser-32 and Ser-36 in H2B histone, which have all been identified as the sites for cyclic AMP-dependent as well as for cyclic GMP-dependent protein kinases. However, the enzyme is not inhibited by the regulatory subunit nor by the protein inhibitor described for cyclic AMP-dependent protein kinase. The enzyme also differs from cyclic GMP-de-pendent protein kinase in physical and kinetic properties. The exact relationship of this new species of protein kinase to cyclic nucleotide-dependent enzymes has remained unexplored.View full abstractDownload PDF (425K) -
Characterization of Carbohydrate-Free Fragment 1•2 (Fragment X) Released by the Action of Plasma Kallikrein and Its Biological ActivityYong Nam HAN, Hisao KATO, Sadaaki IWANAGA, Sachiko OH-ISHI, Makoto KAT ...1978 Volume 83 Issue 1 Pages 213-221
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSFragment X, one of several fragments released from bovine plasma high-molecular-weight (HMW) kininogen by the action of bovine plasma kallikrein, was isolated and characterized. The amino acid composition of fragment X was identical with that of a previously characterized glycopeptide, fragment 1•2. However, it had no carbohydrate components. Fragment X was further cleaved by plasma kallikrein into two peptide fragments, named fragment Y and the previously characterized fragment 2. The NH2-terminal sequences up to 15 residues of fragment X and fragment Y were identical with that of fragment 1•2. Further, peptide maps of the tryptic digests of fragment 1•2 and fragment X were indistinguishable, except for the spots corresponding to glycopeptides, which were only found in the digest of fragment 1•2. These results show fragment X to be a carbohydrate-free fragment 1•2, which is a precursor peptide composed of fragment Y and fragment 2. The present studies also provide further evidence for microheterogeneity of the fragment 1•2 region in bovine HMW kininogen, in addition to the previously reported microheterogeneity with amino acid substitutions caused by genetic variants in the same region.
Fragment X, the carbohydrate-free fragment 1•2, showed strong inhibitory activity upon the kaolin-mediated activation of Hageman factor (factor XII), as does hexadimethrine bromide. It also prolonged the calcium-clotting time of citrated rat plasma. These results indicate that fragment X has activities similar to those of fragment 1•2, which has recently been identified as one of the contact activation inhibitors. The oligosaccharide chains attached to the peptide chain in fragment 1•2 are not essential to the inhibitory activity.View full abstractDownload PDF (1769K) -
Yong Nam HAN, Hisao KATO, Sadaaki IWANAGA, Masanobu KOMIYA1978 Volume 83 Issue 1 Pages 223-235
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. Using various purified kallikreins [EC 3. 4. 21. 8] and kininogenases, the process of fragmentation of bovine plasma high-molecular-weight (HMW) kininogen was examined. Bovine plasma kallikrein liberated the previously characterized contact activation inhibitors, fragment 1•2 and fragment X (carbohydrate-free fragment 1•2), in addition to bradykinin, almost simultaneously from the kininogen. Porcine pancreatic and human urinary kallikreins, and snake venom kininogenase released these fragments only slightly, if at all, although all the enzymes produced the vasopeptide kinin very rapidly. On the other hand, the release of kinin from the kininogen by bovine plasmin [EC 3. 4. 21. 7] was insignificant and no release of fragments such as fragment 1•2 and fragment X was observed. Plasmin appeared to destroy rapidly the large polypeptide region, which comprises fragment 1•2, fragment X, and the COOH-terminal part of HMW kininogen. Thus, the release of fragment 1•2 from the kininogen was due to a specific action of plasma kallikrein.
2. Human urinary kallikrein was found to be useful to elucidate a linear polypeptide sequence of the kinin moiety and fragment 1•2 in the kininogen molecule, because the enzyme only releases kinin under certain conditions. After reduction and S-carboxymethylation of the disulfide bonds in urinary kallikrein (URK)-modified HMW kininogen, two polypeptide fragments, named HMW-heavy chain-URK and HMW-light chain-URK, were isolated. These fragments were found to be derived, respectively, from the NH2- and COOH-terminal portions of the parent molecule. Direct Edman degradation up to the 3rd step of HMW-light chain-URK established the sequence Ser-Val-Gin, which is identical with the NH2-terminal sequence of fragment 1•2. Furthermore, on incubation of HMW-light chain-URK with plasma kallikrein, it yielded initially fragment 1•2, fragment X, and the previously identified HMW-light chain. These results indicate that fragment 1•2 and fragment X could be positioned before the HMW-light chain, located in the COOH-terminal portion of whole HMW kininogen.View full abstractDownload PDF (3628K) -
Mayumi FUJIMOTO, Akira KANAYA, Yukihiro NAKABOU, Hiroshi HAGIHIRA1978 Volume 83 Issue 1 Pages 237-242
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSIntestinal ornithine decarboxylase [L-ornithine carboxy-lyase, EC 4. 1. 1. 17] activity was found to show a marked circadian rhythm with a peak 4h after the start of eating in rats on a diet containing protein. In rats with an intestinal blind loop, the enzyme was induced in the portion of the intestine that came in contact with the protein meal, but not in the blind loop. Injection of tetragastrin or CCK-PZ alone had no effect on enzyme induction, but when a protein suspension was introduced into a tied loop of intestine soon after the injection of tetragastrin or CCK-PZ, the enzyme was induced in the segment to almost the same extent as in the intestines of normal rats eating a protein meal.
These results suggest that the circadian rhythm in activity of intestinal ornithine decarboxylase is initiated by release of gastrin, or CCK-PZ, or both, and contact of protein with the small intestine after the intake of food containing protein.View full abstractDownload PDF (474K) -
II. Reduction of Thermoresistant Cytochrome c-552 and Horse Heart Cytochrome c by Ascorbic AcidHiroshi KIHARA, Hiroshi NAKATANI, Keitaro HIROMI, Koyu HON-NAMI, Tairo ...1978 Volume 83 Issue 1 Pages 243-248
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe reductions of thermoresistant cytochrome c-552 and horse heart cytochrome c by ascorbic acid were studied by the stopped-flow method between pH 4 and 10. The results were as follows (1) The reduction of horse heart cytochrome c showed two relaxation decays above pH 8.5, one of which was pseudo-first order, as was the case below pH 8, while the other was nearly concentration-independent. These results were consistent with those reported by Greenwood and Palmer (J. Biol. Chem. (1965) 240, 3660-3663). (2) For the reduction of cytochrome c-552, only a single relaxational decay that obeyed pseudo-first order kinetics was observed. (3) It seems most reasonable to assume that the concentration-independent relaxation process can be attributed to the isomerization reaction accompanying ligand exchange, since it is known that only horse heart cytochrome c exhibits ligand exchange, involving a residue with pK 9.3.View full abstractDownload PDF (352K) -
Masao OHASHI, Tsuneo OMURA1978 Volume 83 Issue 1 Pages 249-260
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSSonic extracts of bovine liver and kidney mitochondria showed a weak but definite NADPH-cytochrome c reductase activity. 80% of the total reductase activity was due to contamination by microsomal NADPH-cytochrome c reductase, as shown by inhibition of the microsomal reductase with the antibody. However, the residual NADPH-cytochrome c reductase activity of mitochondrial extracts was intrinsic to mitochondria.
The NADPH-cytochrome c reductase activity of these mitochondrial sonic extracts was stimulated by the addition of adrenodoxin reductase, which had been purified from adrenal cortex mitochondria, and the increase of the reductase activity was proportional to the amount of adrenodoxin reductase added. The antibody against pure adrenodoxin inhibited adrenodoxin reductase-dependent NADPH-cytochrome c reductase activity almost completely. The presence of adrenodoxin in liver and kidney mitochondrial extracts was furthur confirmed by Ouchterlony double diffusion and quantitative immunoprecipitation.
When the sonic extracts of liver and kidney mitochondria were titrated with adrenodoxin which had been purified from bovine adrenal cortex mitochondria, NADPH-cytochrome c reductase activity was enhanced in proportion to the amount of adrenodoxin added. Although the antibody against pure adrenodoxin reductase did not inhibit the catalytic activity of the reductase, specific removal of the reductase in mitochondrial extracts by immunoprecipitation was utilized to demonstrate the immunochemical identity of the component in liver and kidney mitochondria with adrenodoxin reductase. Their identity was confirmed by Ouchterlony double diffusion. Thus, the NADPH-cytochrome c reductase activity in liver and kidney mitochondrial extracts is composed of adrenodoxin and adrenodoxin reductase, which are both molecularly identical with those in adrenal cortex mitochondria; these two mitochondrial components may function in the hydroxylation of steroid compounds in liver and kidney mitochondria as an NADPH-cytochrome P-450-reducing system.View full abstractDownload PDF (2007K) -
Interaction with DNA and Acetylation by Calf Thymus EnzymeKentaro HORIUCHI, Daisaburo FUJIMOTO, Yasuhiko SETO, Shumpei SAKAKIBAR ...1978 Volume 83 Issue 1 Pages 261-267
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSSequential polypeptides (Lys-Gly-Gly)5 and (Lys-Gly-Gly)10 were synthesized as models for the N-terminal region of H4 histone and their interactions with DNA were studied. The ability of (Lys-Gly-Gly)10 to precipitate DNA was found to be much higher than that of (Lys-Gly-Gly)5. For example, at the physiological salt concentration, (Lys-Gly-Gly)10 precipitates DNA but (Lys-Gly-Gly)5 does not. Both peptides could be acetylated by a partially purified histone acetyltransferase preparation derived from calf thymus. e-Amino groups of lysyl residues were the sites of the acetylation. DNA-cellulose chromatography of the products indicated that acetylation weakened the interaction of the peptides with DNA.View full abstractDownload PDF (467K) -
Characterization and N-and C-Terminal SequencesMitsuyoshi MORII, Shoji ODANI, Takehiko KOIDE, Tokuji IKENAKA1978 Volume 83 Issue 1 Pages 269-277
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSTwo forms of alpha-l-antitrypsin (α1-AT), α1-AT(I), and αI-AT(II), were separately obtained from human sera which had been pooled and stored for 3 to 6 months at -20°C by a combination of ion-exchange chromatography, gel-filtration, and affinity chromatography.
The N-terminal amino acid sequences of α1-AT(I) and αI-AT(II) were tentatively determined as Glu-Asp-Pro-Gln-Gly-Asp-Ala-Ala-Gln-Glu-Thr-Asp-Thr-Ser-His-(His)- and Glu-Thr-Asp -Thr-Ser-Hi s-His-Asp-G In-Asp-Ser-Pro-Thr-Phe-Asn-Lys-Leu-Thr-Pro-Asn-Leu-Ala-Glu-Phe-, respectively. The amino acid sequence of α1-AT(II) corresponds to the sequence beginning at the tenth glutamic acid residue from the N-terminus of α1-AT(I). Thus, α1-AT(II) may arise by cleavage of the Gln-Glu bond in α1-AT(l) by an enzyme either originally present in the serum or produced by contaminating microorganisms. Based on a combination of the N-terminal sequences of α1-AT(l) and α1-AT(II), the sequence of the N-terminal 33 residues of α1-AT is tentatively proposed.
α1-AT isolated from fresh human plasma had the same N-terminal amino acid sequence as α1-AT(I).
The C-terminal amino acid sequences of the three ai AT's were identified as -Gln-Lys by the carboxypeptidase digestion method.
Amino acid analysis of performic acid-oxidized α1-AT showed that this protein contained one mole of cysteine residue per mole of protein, which was linked to a free cysteine through a disulfide bond.
Most of the α1-AT preparations inhibited bovine trypsin at a molar ratio of 1:1. However, certain preparations bound more than one mole of trypsin per mole of inhibitor.View full abstractDownload PDF (1170K) -
Koei HAMANA, Koichi IWAI1978 Volume 83 Issue 1 Pages 279-286
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe glucocorticoid (cortisol)-receptor complex from rat liver cytoplasm was interacted with various chromatin preparations from rat tissues in a cell-free system. The complex showed the highest extent of binding to liver chromatin among liver, thymus, prostate, and uterus chromatins but the same extent of binding to DNAs isolated from the four tissues. Chemical analyses of these chromatins suggest that some qualitative differences in the nonhistone protein components may be responsible for the different extents of binding. The complex also showed two-fold higher extents of binding to the aggregate chromatin fraction and dehistonized chromatin than to the intact liver chromatin, but half or lower extents of binding to the soluble chromatin fraction, deproteinized chromatin, etc. These various extents of binding could be related to the nonhistone protein content of each chromatin fraction, but not to the histone content. This was further supported by similar binding experiments using various chromatin preparations treated with DNases or proteases.
The cytoplasmic cortisol-receptor complex had the same sedimentation coefficient of about 4S in the absence and presence of 0.3M NaCl. An apparently identical 4S complex was released from the complex-bound chromatin or nuclei by 0.3M NaCI extraction or by DNase or protease digestion. A 6-7S complex existed only in the salt extract and could again bind to DNA in 0.3M NaCl to a much larger extent than the 4S complex in the extract. This 6-7S complex may be a combined form of the 4S complex and its acceptor nonhistone protein molecule. These results also support the conclusion that the cortisolreceptor complex binds to some nonhistone protein components and DNA regions in the liver chromatin. These binding characteristics may imply the recognition and activation of the selected gene for the steroidinduced transcription.View full abstractDownload PDF (1146K) -
Kyoichi KOBASHI, Naomi TERASHIMA, Sachiko TAKEBE, Jun'ichi HASE1978 Volume 83 Issue 1 Pages 287-293
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSBased on the characteristic of hydroxamic acid that it is a potent and specific inhibitor of urease activity, investigations were performed for the establishment of an enzymatic method for the determination of hydroxamic acid and its application to the assays of some enzyme activities.
Crude urease prepared from jack beans was preincubated with the sample solution containing 0.5-10 nmol of hydroxamic acid under the standard conditions and the residual urease activity was measured colorimetrically. A linear correlation was observed between logarithmic concentrations of hydroxamic acid and the inhibition percentage ranging from 20 to 80%. According to the standard relation obtained, hydroxamic acid was determined or detected with higher sensitivity in the following examples: 1) distribution of nicotinohydroxamic acid in the tissues of rats after oral administration, 2) stability of caprylohydroxamic acid in animal food to which the compound had been added as a growth-promoting agent, 3) qualitative detection of hydroxamic acid on a paper chromatogram, 4) applications of this method to the assays of the formation of acetyl CoA by the pyruvic oxidase system or of acetyl phosphate by the acetokinase system. This new method had advantages in easiness and sensitivity over the general method hitherto used, which is based on the ferric-hydroxamic acid complex formation in an acidic solution. However, the power and the rate of inhibition were dependent upon the acyl residue of hydroxamic acid and therefore authentic hydroxamic acid was necessary for the determination.View full abstractDownload PDF (564K) -
Purification and CharacterizationMotoyuki YAJIMA, Koichi HOSODA, Yoshinori KANBAYASHI, Tsutomu NAKAMURA ...1978 Volume 83 Issue 1 Pages 295-303
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSFollowing our previous report (Sumi, T. & Ui, M. (1975) Endocrinology 97, 352) that the injection of pertussis vaccine into rats enhanced their secretory response to various insulin secretagogues 3 to 10 days after the vaccination, purification of a factor responsible for this sustained enhancement of insulin secretion was undertaken from the culture media of Bordetella pertussis (strain Tohama, phase I). An active factor present in the supernatant of 48-h liquid cultures of B. pertussis was purified by sequential application of column chromatographies on hydroxyapatite, CM-Sepharose, concanavalin A-Sepharose and Biogel P-100. Bioassay of the active factor was carried out on the basis of enhancement of the insulin secretory response of rats to an intraperitoneal glucose load 3 days after the injection of the active factor. Roughly 20% of the active factor present in the culture medium was recovered as protein at 1300-fold purification. The purified protein, termed islets-activating protein (IAP), showed a single band on polyacrylamide gel electrophoresis and had a molecular weight of 77, 000. Only one precipitation line was detected between purified IAP and anti-IAP antiserum by the double immunodiffusion technique. The purified IAP, when injected at as low a dose as 0.02 to 0.1μg per rat, doubled the insulin secretory response of rats to glucose loading carried out 3 days later.View full abstractDownload PDF (1015K) -
Motoyuki YAJIMA, Koichi HOSODA, Yoshinori KANBAYASHI, Tsutomu NAKAMURA ...1978 Volume 83 Issue 1 Pages 305-312
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe biological activities were studied of a new protein, islets-activating protein (IAP), purified from the culture medium of Bordetella pertussis. Rats injected intravenously with lμg of purified IAP exhibited markedly enhanced insulin secretory responses to glucose, glucagon, epinephrine, and sulfonylureas over a period from 3 to 10 days after the injection. The degree and duration of the enhancement were proportional to the dose of IAP; the maximal effect induced by 1-2μg of IAP persisted for as long as 2 months. There was a highly significant correlation between the enhancement of insulin secretion and suppression of epinephrine hyperglycemia over a wide range of doses of IAP, indicating that suppression of epinephrine hyperglycemia resulted from hypoglycemic action of insulin secreted in response to epinephrine challenge. Additional actions of IAP were observed in mice; mice treated with higher doses of IAP showed symptoms of leukocytosis and became sensitive to lethal doses of histamine. No such symptoms were observed when lower doses of IAP were injected into mice. Thus, it is concluded that IAP is a protein primarily possessing a unique action to potentiate insulin secretory responses of experimental animals to nutritional and hormonal stimuli.View full abstractDownload PDF (617K) -
Takehiko SAKURAI, Shoko MIYAZAWA, Takashi HASHIMOTO1978 Volume 83 Issue 1 Pages 313-320
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESS1. Rats were fed on a diet containing 0, 1, 2, or 4% di-(2-ethylhexyl) phthalate (DEHP), a widely used plasticizer, for four weeks.
2. The level of plasma triglyceride was decreased in both the I% DEHP and the 2% DEHP groups maintained for I to 2 weeks, but that of cholesterol was not changed. Plasma free fatty acid and ketone bodies increased in all DEHP groups.
3.The level of blood glucose was depressed to about 80% in the 2% and the 4% DEHP groups. Liver glycogen decreased markedly. Isotopic incorporations of 14C from [2-14C]pyruvate into blood glucose and liver glycogen were decreased. The changes in the contents of intermediates in the liver indicate that gluconeogenesis is inhibited at the reaction (s) between 3-phosphoglycerate and fructose 1, 6-diphosphate.
4. Hepatic fatty acid synthesis increased about 2-fold on DEHP administration. The content of phospholipid in the liver was increased, whereas that of triglyceride was decreased. The rate of phospholipid synthesis was increased, but that of triglyceride was not changed.View full abstractDownload PDF (549K) -
Shigeru KIMURA, Yutaka AKASHI, Minoru KUBOTA1978 Volume 83 Issue 1 Pages 321-323
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSAn elastic protein, connectin, was prepared from carp skeletal muscle by the alkaline method with some modifications; collagen contaminations were exhaustively extracted with 1N aceticacid and hot phenol treatment was omitted. This connectin preparation contained a considerable amount of tryptophan, but almost completely lacked hydroxyproline.View full abstractDownload PDF (162K) -
Kiichiro TANAKA1978 Volume 83 Issue 1 Pages 325-327
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe conformation of the chondroitin-4-sulfate calcium salt was investigated by X-ray analysis. The following results were obtained. 1, The repeat length per disaccharide was 0.913nm: 2, The molecular chain had three-fold screw symmetry: 3, The shape of the unit cell was a trigonal prism with dimensions a=b=1.28nm, c=2.74nm, and γ=120°: 4, The number of disaccharide residues in the unit cell was six. Two molecular chains were packed in the unit cell.View full abstractDownload PDF (728K) -
Kishio MATSUURA, Michio OGAWA, Goro KOSAKI, Noshi MINAMIURA, Takehiko ...1978 Volume 83 Issue 1 Pages 329-332
Published: January 25, 1978
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSHuman pancreatic juice collected antiseptically and strictly free from other body fluids and juices, was examined for the isozyme composition of α-amylase. Unlike those of the extract of and exudate from pancreatic tissue, the composition of a-amylase isozyme in the secreted juice was simple and consisted of only two isozymes, a major one and a minor one, and the reason for the difference in the isozyme composition is discussed. The major α-amylase isozyme was obtained in a crystalline state with a molecular weight of 5.4-5.5×104.View full abstractDownload PDF (1540K)
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