巻号一覧
75 巻, 4 号
選択された号の論文の32件中1～32を表示しています
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Hideo INOUE, Hiroaki TANIOKA, Kenzo SHIBA, Akira ASADA, Yukio KATO, Yo ...1974 年 75 巻 4 号 p. 679-687
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーChanges in polyamine metabolism during growth-stimulation of mouse salivary glands by isoproterenol were investigated. In parotid gland, the activity of ornithine decarboxylase [EC 4. 1. 1. 17] increased very rapidly after administration of the drug and reached a maximum after 8 hr. The maximal enzyme activity was about 40-fold higher than that of the unstimulated gland. Thereafter the enzyme activity decreased abruptly and returned to normal after 20hr. The activity of putrescine-dependent S-adenosyl-L-methionine decarboxylase [EC 4. 1. 1. 50] also increased after this treatment and reached a maximum after 12hr, the peak activity being about 7-fold higher than the control activity. Then it decreased and returned to nearly the normal level after 28hr. The putrescine level varied sharply in parallel with the changes in ornithine decarboxylase activity. The spermidine concentration was elevated between 12 and 16hr after isoproterenol administration, while the rate of incorporation of labeled uridine into total cellular RNA reached a maximum after 16hr. These isoproterenol-dependent metabolic alterations were also detected in the submaxillary gland, but they were more delayed and less pronounced than those in the parotid gland, like the changes in weight of the gland.
Pilocarpine, a powerful secretagogue of saliva but not a stimulant of DNA synthesis in salivary glands, had much less effect than isoproterenol in inducing ornithine decarboxylase in the parotid gland. From these results, it is concluded that changes in polyamine metabolism in the salivary glands after isoproterenol administration are closely related to DNA synthesis, rather than to secretion of saliva.抄録全体を表示PDF形式でダウンロード (676K) -
Yoshio IMAI, Ryo SATO1974 年 75 巻 4 号 p. 689-697
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーA simple method has been developed for partial purification of cytochrome P-450 from phenobarbital-induced rabbit liver microsomes. The cytochrome was solubilized with 0.1M phosphate buffer (pH 7.25) containing 0.4% sodium cholate, 20% glycerol, 1mM dithiothreitol, and 1mM EDTA. The solubilized hemoprotein was adsorbed on a column of an ω-amino-n-octyl derivative of Sepharose 4B and then eluted with 1mM Emalgen 913 (a polyoxyethylene nonylphenyl ether) in the same buffer. This method permitted us to purify cytochrome P-450 to a specific content of 8-10 nmoles per mg of protein (40-50% pure assuming a molecular weight of 50, 000 for the cytochrome) with an overall yield of about 35%. The purified preparation was free from both cytochromes b5 and P-420. Its spectral properties were consistent with those reported for the microsomal bound form of cytochrome P-450 and superior in several respects to those of the partially purified preparations of the cytohcrome so far described.抄録全体を表示PDF形式でダウンロード (761K) -
Katsuyuki IMAI, Yumiko TOMITA1974 年 75 巻 4 号 p. 699-705
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーAddition of a basic polypeptide to the α-ketoglutarate dehydrogenase complex resulted in the formation of an insoluble enzyme-polypeptide complex, and the amount of complex formed depended on the amount of polypeptide added. On further addition of the basic polypeptide, the insoluble complex dissolved again. On addition of the amount of polypeptide causing maximal formation of the insoluble complex, the overall reaction of the enzyme was shown to be markedly inhibited. However, the partial reactions catalysed by the three constituent enzymes were not affected significantly by the formation of the complex. The enzyme-polypeptide complex was reversibly dissociated by the addition of 1M KC1. Free lipoamide dehydrogenase [EC 1. 6. 4. 3] and the decarboxylase [EC 1. 2. 4. 2]-lipoate succinyltransferase complex, isolated from the enzyme complex in the presence of 2.5M urea, also formed insoluble complexes in the same manner as the original enzyme complex. It is suggested that the binding of basic polypeptide might interfere with an interaction between the constituent enzymes, resulting in inhibition of the overall reaction, without inhibiting the activities of the constituent enzymes.抄録全体を表示PDF形式でダウンロード (499K) -
Application for the Enzymatic Distinction of Galβ1→4GlcNAc and Galβ1→3GlcNAc LinkagesMidori ARAKAWA, Shun-ichiroh OGATA, Takashi MURAMATSU, Akira KOBATA1974 年 75 巻 4 号 p. 707-714
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーβ-Galactosidase [EC 3. 2. 1. 23] from jack bean meal was purified by heat treatment, followed by Sephadex G-200 and DEAE-Sephadex column chromatography. β-Galac-tosidase from almond emulsin was purified by CM-Sephadex and Sephadex G-200 column chromatography. β-Galactosidase from almond contained β-glucosidase [EC 3. 2. 1. 21] activity.but β-galactosidase from jack bean did not. Both enzyme preparations specifically released galactose from IgG glycopeptide labeled with radioactive sugars.
Aglycon specificities of the purified β-galactosidases were examined by using NaB3H4-reduced milk oligosaccharides. The purified β-galactosidases did not act on terminal β-galactosidic residues in lacto-N-fucopentaitol II and in lacto-N-fucopentaitol III. β-Galactosidase from jack bean meal hydrolyzed Galβ1→4GlcNAc linkage in lacto-N-neotetraitol about 50 times faster than Galβl→3GlcNAc linkage in lacto-N-tetraitol at a substrate concentration of 14μM. β-Galactosidase from almond hydro-lyzed the Galβl→4GlcNAc linkage about 13 times faster than the Galβ1→3GlcNAc linkage under the same conditions. It was possible to cleave more than 90% of the Galβ1→4GlcNAc linkage without any significant hydrolysis of the Galβl→3GlcNAc linkage using β-galactosidase from jack bean meal.抄録全体を表示PDF形式でダウンロード (614K) -
Roichi ITOH, Keizo TSUSHIMA1974 年 75 巻 4 号 p. 715-721
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーComparative studies were made on the effect of diets of various protein contents on the activities of the three enzymes involved in uric acid production from IMP.
In chicken liver and kidney, the specific activities of cytosol 5'-nucleotidase [EC 3. 1. 3. 5], purine nucleoside phosphorylase [EC 2. 4. 2. 1], and xanthine dehydrogenase [EC 1. 2. 1. 37] increased when the casein content of the diet was increased. Of the three, the activity of xanthine dehydrogenase in the liver changed most, increasing 13-fold when the dietary casein content was increased from 5 to 75%. The specific activities of cytosol 5'-nucleotidase and purine nucleoside phosphorylase only increased 2 to 3-fold after this dietary change. The responses of these enzyme activities to change in dietary protein content were less in the kidney than in the liver.
In rat liver, cytosol 5'-nucleotidase and purine nucleoside phosphorylase activities did not change on administration of a high protein diet, but xanthine dehydrogenase activity decreased during adaptation to a low protein diet.抄録全体を表示PDF形式でダウンロード (481K) -
Kuniko OGINO, Kunio NAKASHIMA1974 年 75 巻 4 号 p. 723-730
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーRabbit liver cathepsin B1 [EC 3. 4. 22. 1] was purified from acetone powder of the lysosomal fraction by acid and heat treatments, ammonium sulfate fractionation, affinity column chromatography, and Sephadex G-75 gel filtration. The affinity column was prepared from Sepharose 4B gel by coupling with α-N-benzoyl-L-argininamide (BAA). Cathepsin B1 showed the greatest affinity for the column at pH 4.5, and was eluted by increasing the pH or the concentration of salt. The enzyme had a molecular weight of 24, 000 as found by Sephadex G-100 gel filtration and SDS-polyacryl-amide gel electrophoresis.抄録全体を表示PDF形式でダウンロード (504K) -
Its Comparison with UrokinaseNobuo AOKI1974 年 75 巻 4 号 p. 731-741
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリー1. Plasminogen activator (vascular plasminogen activator) was extracted from the in situ vascular trees of human cadavers, and was partially purified by ammonium sulfate fractionation, zinc precipitation, and ethanol fractionation followed by DEAE-cellulose chromatography and Sephadex G-200 gel filtration. The increase in purity of the final activator preparation over that of the original extract was approximately 200-fold.
2. The vascular activator was labile and rapidly lost its activity at pH values above 8 and below 4. The stability of the activator was dependent on the salt concentration of the medium in which the activator was dissolved; higher salt concentrations tended to stabilize the activator. The activator was inactivated by dithiothreitol but was unaffected by p-chloromercuribenzoate.
3. The vascular activator preparation did not possess any proteolytic activity when tested on fibrin, casein, and denatured hemoglobin, but readily activated plasminogen to plasmin [EC 3. 4. 4. 14]. The optimum pH of the activator for plasminogen activation was around 8.5, which is similar to that of urokinase. The activator and urokinase were found to have the same Km value for plasminogen but had different Km values for the synthetic substrate acetylglycyllysine methyl ester.
4. Gamma-globulins prepared from specific antisera to human urokinase did not inhibit the activity of the vascular activator, whereas they strongly inhibited urokinase activity.
5. The molecular weight of the vascular activator was estimated to be in the region of 80, 000 by gel filtration.
6. It is suggested on the basis of these findings and other evidence previously reported that vascular activator and urokinase are similar, but not identical, enzymes.抄録全体を表示PDF形式でダウンロード (877K) -
Masao TAKEDA, Sueo MATSUMURA, Yôko NAKAYA1974 年 75 巻 4 号 p. 743-751
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーTwo protein kinases (protein kinases A1 and A2) [EC 2. 7. 1. 37] were partially purified from rat liver chromatin by salt extraction followed by Sephadex G-200 gel filtration and phosphocellulose column chromatography. These kinases catalyze the transfer of the terminal phosphate of ATP to specific seryl and threonyl residues of nuclear non-histone phosphoproteins. Using sodium dodecyl sulfate-polyacrylamide gel electro-phoresis the phosphoproteins were shown to be heterogeneous; each protein kinase phosphorylates different protein species. Casein and phosvitin also serve as effective substrates, but histone and protamine are less than 7% as active as casein. Adenosine 3', 5'-monophosphate does not stimulate or inhibit these enzymes. The molecular weight was estimated by the gel filtration procedure to be 2.3×105 for protein kinase A1 and 4.0×104 for protein kinase A2. Protein kinase A1 and A2 show Km values for ATP of 6×lO-6M and l×l0-5M, Km values for casein of 1.2g/liter and 0.4g/liter; and pH optima of about 7.5 and 8.0, respectively. By subcellular fractionation with non-aqueous solvents, these protein kinases were shown to be localized also in cytoplasm although the specific activities are one-twentieth of that found in chromatin.抄録全体を表示PDF形式でダウンロード (2446K) -
Iwao OHTSUKI1974 年 75 巻 4 号 p. 753-765
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリー1. The fine localization of anti-troponin antibody along the thin filament and in the structure of troponin-tropomyosin paracrystal was studied by electron microscopy.
2. Anti-troponin antibody is distributed along the whole thin filament at regular intervals of 380Å.
3. Anti-troponin antibody makes reconstituted troponin-tropomyosin-actin filaments form a bundle with transverse striations repeating with a periodicity of 380Å.
4. The arrangement of tropomyosin molecules in the fibrous paracrystalline structure (Cohen-Longley type) was determined, mainly by examining the end portion of the paracrystals.
5. Taking the arrangement of tropomyosin molecules mentioned above and the previous finding that troponin binds to a localized region in tropomyosin paracrystals (Nonomura et al., 1968) into consideration, it was concluded that troponin binds to a region of the filamentous tropomyosin molecule 270Å (two-thirds the molecular length of tropomyosin) from one end.
6. Tropomyosin treated with dextran sulfate derivatives forms a paracrystalline structure different from the Cohen-Longley type in the presence of divalent cations. The paracrystal shows 540Å periodicity.抄録全体を表示PDF形式でダウンロード (6570K) -
Haruko FUJIMORI, Masatake OHNISHI, Keitaro HIROMI1974 年 75 巻 4 号 p. 767-777
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーThe effects of chemical modification by N-bromosuccinimide (abbreviated as NBS)** of saccharifying α-amylase from Bacillus subtilis upon the hydrolysis of several sub-strates, i. e., maltooligosaccharides (Gn; G2 to G15), phenyl α-maltoside (φM) and cycloheptaamylose (CG7), and also upon glucosyl transfer from maltose to phenyl α-gluco-side (φG), were studied.
The effects of the chemical modifiication on the rates of enzyme reaction at three molar ratios of [NBS]/[Enzyme] were significantly dependent on the substrates. The effect decreases in the order; hydrolysis of CG7_??_hydrolysis of φM into G and φG_??_glucosyl transfer from G2 to φG⟩hydrolysis of φM into φ and G2_??_hydrolysis of maltooligosaccharides, G2_??_G15.
The following trends are noteworthy: i) The effect on maltooligosaccharides is relatively small and almost independent of the degree of polymerization, ii) Distinct differences in the effects are observed for the two different modes of hydrolysis of φM; the rate of φM→G+φG is much more strongly affected than that of φM→φ+G2. iii) The effect on CG7 is considerably larger than that on the maltooligosaccharides. iv) The effect on glucosyl transfer from G2 to φG is remarkable in comparison with that on the hydrolysis of maltooligosaccharides.
Based on these results, the location and the role of the modified tryptophan residue were discussed.抄録全体を表示PDF形式でダウンロード (755K) -
Hideyuki NAGASHIMA, Masaaki MASUBUCHI, Zensaku YOSIZAWA1974 年 75 巻 4 号 p. 779-786
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPathological and normal human biles were fractionated centrifugally in the presence of salts. Of the resulting fractions, the major fraction (Fr. 2) obtained from pathological bile showed a strong coagulating effect on calcium carbonate suspension in water, whereas the fractions obtained from normal bile did not show any significant effect.
Further fractionation on DEAE-Sephadex A-25 of Fr. 2 from the pathological bile afforded several subfractions. The major subtractions (Fr. 2-0.1 and Fr. 2-0.2) showed a very strong coagulating effect and were homogeneous on cellulose acetate electrophoresis. These fractions were characterized as sulfated glycoproteins by chemical and infrared spectral analyses.
The present data together with previous observations suggest that sulfated glycoproteins are abnormal components in bile, responsible for gallstone formation.抄録全体を表示PDF形式でダウンロード (615K) -
Akio ITO1974 年 75 巻 4 号 p. 787-793
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーTreatment of rat liver microsomes with cathepsin D [EC 3. 4. 4. 23] resulted in the selective solubilization of NADH-cytochrome b5 reductase [EC 1. 6. 2. 2.], leaving other electron transferring components such as cytochrome b5, NADPH-cytochrome c re-ductase [EC 1. 6. 2. 4] and cytochrome P-450 still attached to the membrane. The rate and the extent of reduction of membrane-bound cytochrome b5 by NADH were studied with digested microsomal samples containing different amounts of the cyto-chrome b5 reductase. The analysis of the reduction kinetics of the cytochrome b5 suggested the presence of the assemblies of cytochrome b5 and its reductase in the original microsomal membrane. An assembly seems to contain about five molecules of NADH cytochrome b5 reductase and about fifty molecules of cytochrome bs gath-ered togather in the membrane.抄録全体を表示PDF形式でダウンロード (599K) -
Dennis B. McNAMARA, Prakash V. SULAKHE, Jagat N. SINGH, Naranjan S. DH ...1974 年 75 巻 4 号 p. 795-803
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーHeart sarcolemmal fraction containing Na+-K+ stimulated ATPase [EC 3. 6. 1. 3], Mg2+ ATPase, Ca2+ ATPase and adenylate cyclase was isolated by hypotonic shock and 0.4M LiBr treatments. The time required for the isolation was about 5hr. The specific activities of Na+-K+ ATPase (lOμmoles Pi/mg per hr) and adenylate cyclase (280pmoles cyclic AMP/mg per min) in the dog heart membrane fraction were 7-8 fold of those in the heart homogenate. The sarcolemmal fraction consisted of sacs of varying shapes and sizes and was devoid of most of the mitochondrial, microsomal and myofibril contaminants. The properties of Na+-K+ ATPase in the membrane fraction were compared with those of the Nal treated membrane fraction. The enzyme activity in the membrane fraction was lower than that of the Nal treated preparation. The Km values for the Na+-K+ ATPase of the membrane fraction and Nal treated membrane fraction were 0.77 and 0.70mM (MgAPT) respectively. The pH optimum for Na+-K+ ATPase activity in these preparations was about 7.5. Different monovalent cations such as Rb+, NH4+, Cs+, Li4, and choline4 were poor substitutes for K+ in activating the Na+-K+ ATPase in these preparations. The mean values for the concentrations of K+ varied from 1.2-1.5mM and those for Na varied from 12-16mM for half maximal activation of Na+-K+ ATPase in these preparations. The mean values for the concentrations of ouabain varied from 3.1-3.2μM and those for calcium varied from 1.0-1.2mM for 50% inhibition of Na+-K+ ATPase in these preparations. Various other cardioactive agents failed to influence Na+-K+ ATPase activity of the heart sarcolemma.抄録全体を表示PDF形式でダウンロード (1714K) -
IX. Reconstitution of an Active Derivative from Two Inactive Fragments and the Contribution of Tryptohpan-93Takehiko KOIDE, Tokuji IKENAKA, Kiyoshi IKEDA, Kozo HAMAGUCHI1974 年 75 巻 4 号 p. 805-823
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーCyanogen bromide treatment of soybean trypsin inhibitor (Kunitz) gives two peptide fragments; fragments ABC and D. The isolated fragment ABC or D alone shows no trypsin inhibitory activity. The activity, however, is largely regenerated on mixing the two components at neutral or weakly basic pH. The reconstituted inhibitor, STI-C, had nearly the full native inhibitory activity.
The CD spectrum showed that the reconstitution of the inhibitor was almost complete 40min after mixing, that the half time for the reconstitution was about 3min, and that the basic conformation of native STI was essentially recovered.
STI-C dissociated at acidic pH, or even at neutral or weakly basic pH in the presence of 4M urea.
Lyophilization of the fragments appears to produce species incapable of reconstituting the active inhibitor due to aggregation of the fragments.
STI-C which had been concentrated by lyophilization showed “temporary inhibition.”
One tryptophan residue in STI-C was oxidized by hydrogen peroxide in 10% dioxane with an oxidation curve similar to that of native STI. At 0.8 mole of tryptophan oxidized, STI-C retained about 80% of the native inhibitory activity. After separation of the oxidized STI-C into two fragments by gel filtration in the presence of 4M urea, the modified tryptophan residue was identified as tryptophan-117 in fragment D.
Isolated intact fragments ABC and D were individually oxidized with hydrogen peroxide and mixed at weakly basic pH with an equimolar amount of intact D or ABC, respectively. In both cases, complexes between ABC and D were formed. The CD spectra showed that the complex with tryptophan-117 oxidized had recovered almost the same conformation as H2O2-oxidized STI-C, while the complex with tryptophan-93 oxidized had a rather different conformation.
Trypsin inhibitory activity was found for the complex with tryptophan-117 oxidized, but not for the complex with tryptophan-93 oxidized, indicating that tryptophan-93 plays an important role either in the maintenance of the native structure or in the inhibitory activity of STI, while tryptophan-117 plays a minor role both in the tertiary structure and in the inhibitory activity of STI.
This paper is concerned with the relationship between the inhibitory activity and the conformation of various derivatives of STI-C on the basis of their CD spectra.抄録全体を表示PDF形式でダウンロード (1324K) -
Ryoko KOBAYASHI, Shin-ichi ISHII1974 年 75 巻 4 号 p. 825-835
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーEsters of 6-aminohexanoic acid, glycyl-β-alanine, β-alanylglycine and guanidinoacetyl-glycine were synthesized for use as substrates of bovine trypsin [EC 3. 4. 21. 4]. All of them had the terminal positive charge located at the same distance from the susceptible ester bond as that in the specific trypsin substrates, Nα-protected L-lysine or L-arginine esters, but did not have the corresponding α-amino group of L configuration. Kinetic studies on trypsin-catalyzed hydrolyses of these esters led to the following findings.
1. Removal of the L-α-amino component from lysine substrates, affording esters of 6-aminohexanoic acid, had little effect on Km(app) but reduced kcat by two orders of magnitude.
2. When a hydrophilic-CO-NH-structure was incorporated into the connecting portion between the terminal positive charge and the ester bond, Km(app) became greater by two orders of magnitude. The values were especially large for esters of β-alanylglycine and guanidinoacetylglycine.
3. Even the latter two compounds proved to be bound at the specificity site of trypsin on the basis of inhibition experiments with methylguanidine. Correlation between the pH dependence of kcat/Km(app) and the dissociation constant of the terminal ionizable group of each substrate supported this conclusion.
On the basis of these findings, the importance of the β-carboxyl group of Asp-117 and the α-carbonyl group of Ser-198 of trypsin for its substrate-binding and catalvzinff functions was discussed.抄録全体を表示PDF形式でダウンロード (817K) -
Yousuke SEYAMA, Tamio YAMAKAWA1974 年 75 巻 4 号 p. 837-842
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーA hexosamine-containing glycolipid, comprising about 6.8% of the total lipids, was extracted and purified from the guinea pig red cell membrane. The carbohydrate moiety consisted of glucose, galactose, and N-acetylgalactosamine in equimolar proportions. Analysis of the sugar linkages by methylation of this glycolipid indicated that the C-4 positions of glucose and galactose were substituted by another sugar and N-acetylgalactosamine resided on the non-reducing terminal. The configuration of the glycosidic linkages was established by optical rotation measurements, PMR spectra and specific enzymatic hydrolysis. The structure of this glycolipid was shown to be N-acetylgalactosaminyl β(1→4)-galactosyl-β(l→4)-glucosyl-(l→l)-ceramide. The major fatty acid was C24:0, and the long chain base was mostly 4-sphingenine.抄録全体を表示PDF形式でダウンロード (441K) -
Teruo IWASAKI, Toshifumi KIYOHARA, Mitsuyoshi YOSHIKAWA1974 年 75 巻 4 号 p. 843-851
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPotato proteinase inhibitor IIa complexed with trypsin [EC 3. 4. 4. 4] was incubated at pH 8 with a small excess of trypsin, yielding a low molecular weight active fragment. The active fragment, purified by successive gel filtrations and by treatment with trichloroacetic acid, consists of a single peptide chain with a molecular weight of 4, 800; it has serine as the amino-terminal residue and arginine as the carboxylterminal residue. It exhibits very strong inhibitory activity against trypsin; 1μg inhibits 5.1μg of the enzyme. The active fragment also shows weak inhibitory activity against chymotrypsin [EC 3. 4. 4. 5], which is considerably reduced as compared with that of the native inhibitor. Moreover, the inhibitory activity of the active fragment against a bacterial proteinase, Nagarse, had become negligible.抄録全体を表示PDF形式でダウンロード (702K) -
Taiju KURAMOTO, Seiko ITAKURA, Takahiko HOSHITA1974 年 75 巻 4 号 p. 853-859
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリー1. When mevalonate-2-14C was injected intraperitoneally into toad, radioactive cholic acid* and 5β-bufol were isolated from the gall-bladder bile, while the main bile acids of this Anura, 3, lα, 12α-trihydroxy-5β-cholest-22-ene-24-carboxylic acid, and 3α, 7α, 12α-trihydroxy-5β-cholest-23-enoic acid were found to be unlabeled.
2. The radioactive 5β-bufol was oxidized with lead tetraacetate to cholyl methyl ketone with the liberation of formaldehyde. The cholyl methyl ketone had the same specific radioactivity as the 5β-bufol. The cholyl methyl ketone was degraded into homocholic acid with decreased (16.7%) specific activity. It was concluded that the 26-hydroxylation in the biosynthesis of 5β-bufol occurs in a stereospecific manner.抄録全体を表示PDF形式でダウンロード (524K) -
Hiroshi HATANAKA, Yoko OGAWA, Fujio EGAMI1974 年 75 巻 4 号 p. 861-866
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリー1. L-Ascorbic acid 6-sulfate was synthesized as an analog for natural L--ascorbic acid 2-sulfate by the direct sulfation of L--ascorbic acid with pyridine-sulfur trioxide.
2. Its ultraviolet, infrared, and nuclear magnetic resonance spectra were investigated and compared with those of L--ascorbic acid 2-sulfate.
3. A crude sulfatase preparation from the liver of a marine gastropod, Charonia lampas, hydrolyzed L-ascorbic acid 2-sulfate to give L-ascorbate and sulfate. L-Ascorbic acid 6-sulfate was also, although more slowly, hydrolyzed by this enzyme preparation.抄録全体を表示PDF形式でダウンロード (366K) -
Noriko FUKUI, Akiko FUJITA, Hidesato OHTSUKA, Yoshiaki MIURA1974 年 75 巻 4 号 p. 867-873
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーTyrosine transaminase [L-tyrosine: 2-oxoglutarate aminotransferase, EC 2. 6. 1. 5] and L-ornithine decarboxylase [EC 4. 1. 1. 17] were induced in the liver of adrenalectomized rats by partial hepatectomy. The induction of these enzymes in regenerating liver is, therefore, not due to changes in the glucocorticoid concentration in the blood caused by stress. Using these enzyme activities as parameters of early biochemical events induced by partial hepatectomy, the conditions necessary for the regenerative process in isolated, perfused liver were investigated. Neither enzyme was induced on perfusion with synthetic medium. However, ornithine decarboxylase was induced on perfusion with serum, even without partial hepatectomy, although it was induced to a greater extent in partially hepatectomized liver. Tyrosine transaminase was induced in isolated liver perfused with medium containing serum, only when more than 70-80% of the liver had been removed. Thus, it was concluded that in isolated, perfused liver, both the addition of serum to the perfusion medium and partial hepatectomy were necessary to induce the two enzymes.抄録全体を表示PDF形式でダウンロード (556K) -
Ayako MATSUSHIMA, Shojiro YAMAZAKI, Yuji INADA1974 年 75 巻 4 号 p. 875-879
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーA chemical modification reagent, tert-butyl hypochlorite (TBH), which discriminates the states of imino groups in proteins, was applied to various proteins, and the following observations were made. Imino groups in proteins could be classified into reactive type and less-or non-reactive type. The percentage of reactive type imino groups in each protein was as follows; 31% for myosin, 48% for ribonuclease A [EC 2. 7. 7. 16], 37% for α-chymotrypsin [EC 3. 4. 4. 5], 28% for subtilisin [EC 3. 4. 4. 16], 32% for β-lactoblobulin, 37% for serum albumin, 28% for metmyoglobin, 21% for methemoglobin, 39% for cytochrome c, and 26% for G-actin. Imino groups of the less-or non-reactive type appeared to be closely associated with the secondary structure of proteins and the percentage of these imino groups was discussed in relation to the contents of α-helix structure and β-structure.抄録全体を表示PDF形式でダウンロード (385K) -
Etsushiro DOI1974 年 75 巻 4 号 p. 881-887
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリー1. Cathepsin A, the enzyme which hydrolyzes carbobenzoxy-L-glutamyl-L-tyrosine, was obtained from pig kidney. The enzyme was labile after dialysis but was stabilized by the addition of sucrose or KC1. In the presence of both stabilizers, the enzyme was active between pH 3 and 6.
2. The enzyme activity was inhibited by diisoprophyl fluorophosphate and sulfhydryl reagents such as p-chloromercuribenzoic acid (PCMB). The enzyme was not activated by cysteine but enzyme which had been treated with PCMB was reactivated by cysteine.
3. The possible identity of cathepsin A and catheptic carboxypeptidase is discussed.抄録全体を表示PDF形式でダウンロード (515K) -
Etsushiro DOI, Yukio KAWAMURA, Teruyoshi MATOBA, Tadao HATA1974 年 75 巻 4 号 p. 889-894
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPig kidney contained two different molecular sizes of cathepsin A. The enzymes of larger molecular size (cathepsin A, L; MW>500, O00) and of smaller molecular size (cathepsin A, S; MW=100, 000) were separated by gel chromatography on Sephadex or by sucrose gradient centrifugation. The two enzymes have different physical properties but very similar enzymatic properties. These enzymatic properties are almost same as those of crude enzyme preparation.抄録全体を表示PDF形式でダウンロード (489K) -
VIII. Idiosyncrasy of Ca2+-dependent Competence for DNAAkira TAKETO1974 年 75 巻 4 号 p. 895-904
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーUsing φA replicative-form DNA (RF), the properties of the calcium-dependent trans-fection system were investigated in detail. Calcium ions seem to induce preferential uptake of double-stranded DNA by the treated bacteria, rather than causing nonspecific or irreversible increase in the cellular permeability. In this system, Mg2+ was ineffective as a substitute for Ca2+. Transfection does not take place when cells suitably pretreated with Ca2+ are mixed with DNA in media deficient in the cation. In 50mM CaCl2, viral DNA can infect competent cells at 0°C. The yield of transfectants decreased markedly if the Ca2+-treated bacteria and DNA were mixed at temperatures higher than 20°C and plated directly. Efficient transfection, however, occurred when DNA-cell mixtures preincubated at higher temperatures were plated after quenching at 0°C. Cells pretreated with EDTA did not develop any competence upon subsequent Ca2+ treatment, suggesting possible involvement of surface lipopolysaccharide and/or lipoprotein in the interaction with DNA. Dialyzed supernatant obtained from EDTA-cell mixture inhibited the transfection. The Ca2+-dependent transfection is inhibited by low concentrations of phosphate and is very sensitive to ionic detergents such as cetyltrimethylammonium bromide or sodium dodecyl sulfate. Double-stranded heterologous DNA considerably inhibits RF infection, while the inhibitory effect of singlestranded DNA or RNA is relatively small. The infection occurs in the presence of certain metabolic inhibitors such as dinitrophenol or sodium azide. These results suggest that the Ca2+-dependent uptake of DNA is physicochemical or at least energyindependent. The competence level of bacterial mutants deficient in phospholipase A was as high as that of wild-type cells. The effect of culture conditions such as growth phase or temperature was also examined. Based on these results, the mechanism of Ca2+-dependent competence was discussed with particular reference to liquid crystallization of the cell envelope lipids.抄録全体を表示PDF形式でダウンロード (728K) -
IV. Kinetic StudiesHiroshi YOSHIDA1974 年 75 巻 4 号 p. 905-911
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーA new mechanism for the action of Fusarium phosphodiesterase-phosphomonoesterase was proposed, in which an “Ordered Uni Ter” mechanism for the hydrolysis of phosphodiester and an “Ordered Uni Bi” reaction for that of phosphomonoester are combined. Rate equations were derived from this mechanism. Comparision of the equations with the previously reported results showed that inorganic phosphate should be the last product released by the enzyme. The hydrolysis of bis-p-nitrophenyl phosphate was analyzed by means of these equations and some kinetic constants were determined. p-Nitrophenol was a linear noncompetitive inhibitor with both bis-p-nitrophenyl phosphate and p-nitrophenyl phosphate as substrates. The rate of liberation of inorganic phosphate from mixtures of the two phosphate esters agreed well with the value calculated from the equations. These results are consistent with the proposed mechanism.
Quantitative analyses of the effects of adenosine, guanosine, cytidine, and uridine on the hydrolysis of p-nitrophenyl phosphate revealed that these ribonucleosides are linear noncompetitive inhibitors. The orders of magnitude of their slope and intercept inhibition constants are in the sequence U>>A>C>G and U>>G>A>>C, respectively.抄録全体を表示PDF形式でダウンロード (474K) -
Takeo YOSHINAGA, Hirobumi TERAOKA, Katsura IZUI, Hirohiko KATSUKI1974 年 75 巻 4 号 p. 913-924
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーThe molecular properties of phosphoenolpyruvate carboxylase [EC 4. 1. 1. 31] of Escherichia coli W were studied by physical and chemical methods. The physicochemical properties found are as follows: molecular weight, 361, 000; sedimentation coefficient, s°20, w=13.3×l0-13sec; diffusion coefficient, D°20, w=3.45×lO-7cm2•sec-1; apparent partial specific volume, _??_=0.736ml•g-1; and molecular ellipticity, [θ]222=-13, 400. The enzyme was found to be composed of 4 identical subunits, each of which contained a single polypeptide chain having a serine residue as the NH2- terminal.
Titration experiments with SH-blocking reagents and amino acid analysis of performic acid-oxidized enzyme revealed the presence of 8 moles of SH groups per mole of subunit and the absence of disulfide linkages. The enzyme retained its full activity even after modification of 2 SH groups with 5, 5'-dithiobis(2-nitrobenzoic acid). Inactivation occurred on titration of 2 additional SH groups with N-ethylmaleimide. The residual 4 SH groups could not be titrated with these reagents without prior denaturation of the enzyme with SDS.
The differences in molecular weight and amino acid composition data for the enzymes of three enteric bacteria, Escherichia coli strains W and B, and Salmonella typhimuriuw strain LT-2 are discussed.抄録全体を表示PDF形式でダウンロード (2452K) -
Kihachiro HORIIKE, Kiyoshi SHIGA, Akio ISOMOTO, Toshio YAMANO1974 年 75 巻 4 号 p. 925-929
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (302K) -
IV. Essential Requirement of the 2-Acetamide-carbonyl Group for the Enzymatic HydrolysisKazuhiko YAMAMOTO1974 年 75 巻 4 号 p. 931-933
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (172K) -
Kenji FUKADA, Yasumi OHSHIMA, Tadao HORIUCHI1974 年 75 巻 4 号 p. 935-938
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (247K) -
Kadiman SIHOTANG1974 年 75 巻 4 号 p. 939-941
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (206K) -
Kosuke ICHIHARA, Emi KUSUNOSE, Masamichi KUSUNOSE1974 年 75 巻 4 号 p. 943-946
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (228K) -
Yousuke SEYAMA, Tamio YAMAKAWA1974 年 75 巻 4 号 p. 947-950
発行日: 1974/04/25
公開日: 2008/11/18
ジャーナル フリーPDF形式でダウンロード (1652K)
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