A thermophilic alkalophile (Bacillus strain TX-3) which produces D-xylose isomerase (EC 5.3.1.5) in an alkaline medium over 55°C was isolated from soil samples.
The D-xylose isomerase was extracted from cells of this strain and purified 21-fold by DEAE-Toyopearl and hydroxyapatite chromatographies and gel filtration. The molecular weight was 140, 000 or 135, 000 by gel filtration or an ultracentrifugal method, respectively; the enzyme consists of three subunits with a molecular weight of 45, 000. The Km values for D-xylose and D-glucose were 0.1 M and 0.29 M, while V_max values were 28.6 and 1.6 μmol/min/mg protein, respectively. The optimum pH for activity was 7.5-9 and the optimum temperature was 80°C.
This enzyme was activated by the addition of Mn²⁺, Co²⁺, or Mg²⁺, but considerable activity was observed in the absence of these metal ions. If the enzyme was treated with EDTA, however, it showed no activity in the absence of metal ions, and its activity was restored by the addition of Mn²⁺, Co²⁺, or Mg²⁺. This enzyme was quite tolerant to SDS, and the residual activity was 50% after treatment with 5% SDS solution at 60°C for 30 min. Metal ions such as Mn²⁺ or Co²⁺ enhanced the inactivation of the enzyme with SDS.

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We isolated two major stimulators of PGI₂ production from fetal calf serum (PCS) by ultra filtration, Sephadex G-10 gel filtration and QAE-Sephadex column chromatography. These stimulators were identified as xanthine and uric acid.
The stimulatory effects on PGI₂ production of xanthine-related compounds and aromatic hydroxy compounds were examined using rat aortic rings. 2-Amino-6, 8-dihydroxypurine and 2, 8-dihydroxyadenine accelerated PGI₂ production, but guaiacol and 4, 4'-dihydroxycalcone greatly inhibited it.

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The phytases (EC 3.1.3.26) and acid phosphatases (EC 3.1.3.2) of rice bran were purified. Four acid phosphatases were purified from rice bran: F1 and F2 had phytase activity, but F3 and F4 did not. The optimum pH of F1 and F2 for phytic acid were 4.4 and 4.6, respectively, and those of F1, F2, F3, and F4 for p-nitrophenyl phosphate were 5.1, 5.2, 5.4, and 6.0, respectively. Their molecular weights were estimated to be about 59-70K by SDS polyacrylamide gel electrophoresis, velocity density gradient centrifugation, and gel filtration on Ultrogel. The isoelectric points of F1, F2, F3, and F4 were 5.1, 5.1, 5.6, and 5.9, respectively. F1, F2, F3, and F4 had a violet color and F2 showed an absorption maximum peak at 560 nm. They had broad substrate specificities.

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Changes of the contents and biosynthetic rates of polyamines and enzyme activities involved in polyamine synthesis as affected by dicyclohexylamine (DCHA) were examined in Hiproly barley callus. The incorporation of [1, 4-¹⁴C]putrescine into spermidine increased rapidly after auxin withdrawal, while the incorporation of [1, 4-¹⁴C]putrescine or [diaminobutane 1, 4-¹⁴C]spermidine into spermine increased gently. The addition of DCHA suppressed the incorporation of [3, 4-¹⁴C]methionine or [1, 4-¹⁴C]putrescine into spermidine. In contrast, the incorporation of [3, 4-¹⁴C]methionine or [diaminobutane 1, 4-¹⁴C]spermidine into spermine increased in the callus by treatment of DCHA. The contents of spermine in the callus increased about 2-fold after treatment with 10 mM DCHA. The activity of spermidine synthase in the callus after auxin withdrawal increased rapidly. Inhibition of spermidine synthase by DCHA stimulated spermine synthesis and the activity of spermine synthase was elevated about 10-fold after treatment with 10mM DCHA. However, DCHA had significant effects on the activity of S-adenosylmethionine decarboxylase and the levels of S-methyladenosylhomocysteamine. S-Methyladenosylhomocysteamine contents increased about 20-fold. The changes in the spermine levels paralleled the changes in the S-methyladenosylhomocysteamine contents. These results suggested that in Hiproly barley callus the biosynthesis of spermine were regulated by the levels of aminopropyl donor and that the availability of S-methyladenosylhomocysteamine may be rate-limiting for the synthesis of spermine.

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L-Fucose (L-galactose) dehydrogenase was isolated to homogeneity from a cell-free extract of Pseudomonas sp. No 1143 and purified about 380-fold with a yield of 23%. The purification procedures were: treatment with polyethyleneimine, ammonium sulfate fractionation, chromatographies on phenyl-Sepharose and DEAE-Sephadex, preparative polyacrylamide gel electrophoresis, and gel filtration on Sephadex G-100. The enzyme had a molecular weight of about 34, 000. The optimum pH was at 9-10.5 and the isoelectric point was at pH 5.1. L-Fucose and L-galactose were effective substrates for the enzyme reaction, but D-arabinose was not so much. The anomeric requirement of the enzyme to L-fucose was the β-pyranose form, and the reaction product from L-fucose was L-fuconolactone. The hydrogen acceptor for the enzyme reaction was NADP⁺, and NAD⁺ could be substituted for it to a very small degree. Km values were 1.9 mM, 19 mM, 0.016mM, and 5.6mM for L-fucose, L-galactose, NADP⁺, and NAD⁺, respectively. The enzyme activity was strongly inhibited by Hg²⁺, Cd²⁺, and PCMB, but metal-chelating reagents had almost no effect. In a preliminary experiment, it was indicated that the enzyme may be usable for the measurement of L-fucose.

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The action of Chalara paradoxa glucoamylase (raw-starch-digesting enzyme) was studied with linear and cyclic maltodextrins. Subsite affinities (Aⁱ) of the amylase were evaluated by the subsite theory. The active site was considered to be made up of seven subsites: A₁ = 0.05 kcal/mol, A₂= 4.99 kcal/mol, A₃ = 1.30 kcal/mol, A₄ = 0.77 kcal/mol, A₅= 0.33 kcal/mol, A₆ = 0.21 kcal/mol and A7 = 0.21 kcal/mol. Inhibitions by alpha-, beta-, and gamma-cyclodextrins were competitive for starch digestion by C. paradoxa glucoamylase. The inhibitor constants (Ki) of α-, β-, and γ- cyclodextrin for the amylase were 8.9, 1.4, and 3.9 HIM, respectively. The Michaelis constant (Km) of 6-O-α-maltosyl-α-cyclodextrin digestion was 0.79 mM for the amylase.

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The reabsorption of ammo acids in rat kidney was examined with respect to the Na⁺-gradient stimulated transport system. The time courses for the uptake of ¹⁴C-amino acids by brush border membrane vesicles were compared in the presence of either Na⁺ or K⁺ ions. The uptake of neutral amino acids was stimulated by the presence of a Na⁺-gradient and exhibited the typical "overshoot" phenomenon, whereas the uptake of acidic and basic amino acids was not clearly stimulated by Na⁺. The rate of Na⁺-dependent uptake into the vesicles at 1 min was determined for 20 amino acids, and was high for alanine, cysteine, valine and isoleucine but low in acidic and basic amino acids. In normal rat urine, the free forms of glycine, alanine and glutamic acid were excreted to a great extent, but isoleucine, arginine and sulfur-containing amino acids were excreted to a small extent. These results indicate that the urinary excretion of an amino acid is not necessarily correlated to the extent of its Na⁺-dependent uptake, and that other factors affecting the urinary excretion should also be considered.

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Cytosine deaminase (EC 3.5.4.1) from bakers' yeast, which is labile to heat, the half-life being about 30min at 37°C, was stabilized through immobilization by various techniques. Our purpose was to prepare implantable enzyme capsules for long-term use in cancer chemotherapy [J. Biotechnol., 2, 13 (1985)]. When the enzyme was immobilized on Eupergit C, a commercial epoxy-acrylic resin, the highest yield of apparent enzymic activity was about 80% of the starting activity, and the enzymic activity decayed exponentially at 37°C over a few weeks, the half-life being about 10 days. With lower yields, other commercial adsorbents resulted in good stability; with yields of 20-67 and 21%, and half-lives of 15 and 24 days for Formyl-Cellulofine and CNBr-activated Sepharose 4B, respectively.

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Maesanin, a metabolite isolated from the fruit of Maesa lanceolata (Myrsinaceae), was devoid of antifungal activity. However, when maesanin was combined with sub-inhibitory concentrations of a sesquiterpene dialdehyde polygodial known to affect the fungal cell membrane, antifungal activity was observed. The synergistic growth inhibition in malt extract medium differed according to fungal species. Among the yeasts tested, Candida utilis was shown to be susceptible to the combination of maesanin and polygodial, but Saccharomyces cerevisiae, Schizosaccharomyces pombe, and Hansenula anomala were not. Synergistic action was also observed in the inhibition of cellular respiration of C. utilis. In mitochondrial preparations from C. utilis or rat liver, maesanin alone significantly inhibited NADH oxidase, succinate oxidase, NADH-cytochrome c reductase, succinate-cytochrome c reductase, and succinate-dichlorophenol-indophenol reductase. Polygodial alone had no inhibitory effect on the respiratory chain enzymes. These results suggest that the synergistic effect of polygodial is due to an increased permeability of maesanin through the cell membrane. The antifungal activity of maesanin in combination with polygodial appears to result from respiratory inhibition with its site of action near coenzyme Q of the mitochondrial electron transport system.

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The diastereoselective hydroxylation of milbemycin A₄ (1) at the 13β-position (→2) was performed by cultures of Streptomyces violascens (ATCC 31560). 14, 15-epoxymilbemycin A₄ (3) was formed via a parallel reaction as a byproduct. The conversion and the product ratio, 2/3, were improved by the addition of organic solvents. The best results, i.e., 91% conversion with 92% 2 and 8% 3, were obtained by adding 2.5% DMSO to the culture broth. Oxime 7 was also hydroxylated at the 13β-position by S. violascens under similar conditions. In the case of milbemycin A₃ (9) and D (10), the main products after treatment with S. violascens were the corresponding 14, 15-epoxides, 13 and 14, respectively.

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A thermophilic, N, N'-diacetyIchitobiose((GlcNAc)₂)-producing bacterium, strain X-7u, was isolated from hot spring water and identified as Bacillus lieheniformis. When X-7u was cultivated in a medium consisting of 2.0% colloidal chitin, 0.05% yeast extract and inorganic salts at 50°C under shaking, (GlcNAc)₂ was accumulated to a concentration of 9.6 g/l within 5 days. This corresponded to 46% of the stoichiometric yield of (GlcNAc)₂. The strain also produced a small amount of N, N'N"-triacetylchitotriose. However, neither N-acetylglucosamine nor other oligosaccharides were accumulated throughout the culture period.

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We have already reported that NiA and related compounds had plant-growth-promoting and flower-inducing activities in duckweed, Lemna paucicostata 151. These effects may be concerned with the biosynthesis and metabolism of NAD. So, for the first step, the various enzyme activities related to them were investigated in this study to obtain some fundamental information on the action mechanism of these compounds and metabolites. Extremely high enzyme activity of nicotinamidase and very high enzyme activity of NAD glycohydrolase were found. The enzyme activities of nicotinate phosphoribosyltransferase, quinolinate phosphoribosyltransferase, and nicotinate methyltransferase were easily detected. In contrast, nicotinamide phosphoribosyltransferase and ADP-ribosyltransferase activities were very low and nicotinamide methyltransferase activity was not detectable. NiA and NAm administered to the plant were rapidly incorporated into NAD and metabolized to several compounds. Postulation of the action mechanism is discussed.

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Acyl coenzyme A: alcohol acyltransferase was purified to homogeneity from a strain of Neurospora sp. ATCC 46892 which produces ethyl hexanoate abundantly in the culture broth.¹⁾ The apparent molecular weight was approximately 30, 000. This enzyme acted on various acyl coenzyme A's containing more than a four-carbon linear chain, but not on acetyl coenzyme A, n-propionyl coenzyme A, or the branched-chain acyl coenzyme A's that were examined. It also acted on various linear- and branched-chain alcohols tested. The optimum pH was 8.0, and the optimum temperature, 25°C at pH 8.0. The enzyme was stable from pH 3.0 to 9.0 and up to 43°C, maintaining its original activity. The enzyme activity was strongly inhibited by diisopropyl fluorophosphate and phenylmethylsulfonyl fluoride, but not by unsaturated fatty acids.

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(2R^*, 3R^*)-6-Formyl-7-methoxy-3-methoxymethyl-2-(3', 4'-methylenedioxyphenyl)-2, 3-dihydro-1, 4-benzodioxine, a starting material for haedoxan synthesis, was synthesized from 2, 4-dihydroxybenzaldehyde.

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The naturally occurring insecticides, haedoxans A and D, as well as the artificial congener, haedoxan E, and nine of their Stereoisomers were synthesized in racemic form.

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The reaction of methyl linoleatc hydroperoxides with DNA, nucleosides and DNA bases was investigated by determining the fluorescence formation in the presence of ascorbic acid and Fe²⁺. Methyl linoleate hydroperoxides produced significant fluorescence only with adenosine and with DNA, but not with the other nucleosides tested. Adenine also produced similar fluorescence, suggesting that the amino group at the 6-position reacted preferentially with the lipid oxidation products to produce fluorescence. The pH level did not have any distinct effect on either the intensity or spectrum of fluorescence in the range of 4.0-9.0. Among the degradation products of methyl linoleate hydroperoxides, 2-octenal and 2, 4-decadienal produced fluorescence with adenine even in the absence of FeSO₄ and ascorbic acid. However, none of these carbonyl compounds produced significant fluorescence in the reaction with DNA, FeSO₄ and ascorbic acid. Potassium iodide, hydroquinone, alpha-tocopherol and BHA reduced the amount moiety in DNA reacts with the secondary decomposition products of methyl linoleate hydroperoxides after strand-breaking by radical species derived from methyl linoleate hydroperoxides.

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A clone that contains goat growth hormone (gGH) gene was isolated from a goat genomic library using bovine growth hormone cDNA as a probe. The gGH gene was located on a 5.8-kb EcoRI-HindIII fragment from the data of Southern hybridization analysis, and the gGH gene and its flanking region were completely sequenced. The nucleotide sequence of the region was highly homologous to those of other animals. The nucleotide sequence homologies of the promoter region of the gGH gene were 98% with the bovine, 90% with the porcine, 74% with the human, and 72% with the rat genes. The consensus sequence for the glucocorticoid receptor binding site was found in the first intron of the gGH gene. Comparison of the S'-flanking sequences of the gGH gene with those of other animals revealed that there were three homologous tracts among those sequences. We found conserved sequences in the 3'-flanking region.

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The intergeneric hybridization between Aspergillus niger and Trichoderma viride was studied. The fusion of protoplasts from auxotrophic mutant strains, using a polyethylene glycol solution, resulted in the formation of intergeneric fusants, the fusion frequencies being 10^-5 to 10^-4. The fusant strains were classifiable into two types according to their morphologies. The fusant strains of the first type formed prototrophic conidia and colonies showing an A. niger type morphology on both the minimal and supplemented media. These fusant strains were proved to be haploids by measurement of conidial sizes and DN A contents, and assumed to be recombinants. The fusant strains of the second type formed conidia showing the same nutritional requirements as those of the original auxotrophic mutant strains used for protoplast fusion. These fusant strains formed colonies showing mixed morphologies, between those of A. niger and T. viride, on the minimal medium and grew more slowly than the prototrophic parental strains of A. niger and T. viride. From these results and those of conidia analyses, the fusant strains of the second type were proved to be heterokaryons. Mycelial protoplasts of the fusant strains of the two types regenerated on the hypertonic minimal medium into colonies with morphological features identical to those of the original fusant strains.

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A new type of enzyme reactor was developed, which was based on the fact that enzymes usually migrated faster than substrates and products in a gel chromatographic column. The reactor could allow repeated use of an enzyme without chemical or physical immobilization of the enzyme. The reactor, which was constructed by two columns packed with a gel chromatographic resin, included six steps of operation. In only one step, an enzyme was put on the reactor. By repeating consecutively four steps of six, a substrate could be continuously converted to a product without further addition of the enzyme. In terms of the hydrolysis of maltose to glucose by glucoamylase, it was experimentally demonstrated that the enzyme reactor proposed here could be successfully operated for a long period.

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The complete separation and identification of mono-, di- and tri-α-glucosylated products from stevioside with soluble starch and cyclodextringlucosyltransferase were achieved. Evaluation of the sweetness of each product, in comparison with stevioside, revealed the remarkable improvement in both the intensity and character of sweetness of the products, which were mono- and di-glucosylated at the 13-O-β-sophorosyl moiety (4-hydroxyl group of the terminal β-glucosyl unit). Some decrease in the intensity of sweetness was observed for most of the other products, though the quality of taste of all the other products was significantly or slightly improved (Table I).

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Exposure to some xenobiotics (pentobarbital, 3-tert-butyl-4-methoxyphenoI (BHA), chloretone (acetone chloroform), 1, 1-bis-(p-chlorophenyl)-2, 2, 2-trichloroethane (DDT) and poly chlorinated biphenyls (PCB)) for a 5 hr period increased the concentrations of brain serotonin and 5-hydroxyindole acetic acid (5HIAA). The decrease in the brain serotonin level elicited by p-chlorophenylalanine (PCPA), an inhibitor of serotonin synthesis, was prevented by the concomitant administration of chloretone. The administration of both chloretone and pargyline (an inhibitor of monoamine oxidase) caused significant elevation of the brain 5HIAA level as compared with that in a pargyline control, however, the concentration of brain serotonin was not different between pargyline alone and chloretone plus pargyline. These results show that the increase in the brain serotonin level caused by chloretone is not due to acceleration of brain serotonin synthesis, but to retardation of the degradation of brain serotonin, and the increase in brain 5HIAA caused by chloretone may be due to the reduced removal of SHI A A from the brain. Chloretone plus pargyline caused significant elevation of hypothalamus catecholamines, as compared to in the pargyline control, so the catecholamine turnover rates may be accelerated by the administration of chloretone.

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Tyrosine residues in ricin D were modified with N-acetylimidazole and the saccharide binding properties of the resulting derivatives were examined. The cytoagglutinating activity of ricin D was not altered by acetylation of one tyrosine residue/mol, but decreased greatly upon modification of two tyrosine residues/mol. In the cytoagglutination test, only 6% residual activity was found in the derivative, 2-Ac-ricin D, in which 2.4 tyrosine residues/mol were acetylated. In the presence of lactose, however, one tyrosine residue/mol was protected from acetylation by N-acetylimidazole with a retention of the saccharide binding ability, suggesting the involvement of one tyrosine residue in the saccharide binding. Fluorescence and UV-difference spectroscopic data indicate that the binding ability of the low affinity saccharide-binding site (LA-site) of ricin D remained unchanged after modification of 2 tyrosine residues/mol. The affinity chromatography of the acetylated derivatives of ricin D on the lactamyl- and galactosamine-cellulofine columns suggests that 2-Ac-ricin D binds galactopyranosides only at the LA-site, but lacks the binding ability at the high affinity saccharide-binding site (HA-site). It is postulated that introduction of the bulky acetyl group into the hydroxyl group of the tyrosine residue at the HA-site of ricin D may sterically hinder the binding of saccharides.

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In a search for new salty compounds, sensory analyses of ornithyl-β-alanine (OBA), some amino acid methyl ester hydrochlorides and most amino acids were carried out. OBA was found not only to exhibit saltiness in the presence of a small excess of hydrogen chloride, but also to enhance the saltiness of sodium chloride. Glycine methyl and ethyl ester hydrochlorides were also found to exhibit good saltiness and enhancing effects. Basic and acidic amino acids were found to enhance the saltiness of sodium chloride, although they did not exhibit saltiness by themselves. We found that the intake of sodium ions can be cut by 75%, 50%, and 25% by using OBA, glycine esters and amino acids, respectively.

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A new HPLC system for simultaneous analysis of NAD⁺, NADH, NADP⁺, and NADPH was developed and used to measure the transhydrogenase activity of spinach ferredoxin-NADP⁺ reductase (EC 1.18.1.2, FNR). The system is based on a reverse-phase HPLC with isocratic elution on an ODS column (4.6 × 50 mm). The four nucleotides were completely separated by developing the column with 0.15 M sodium phosphate/citrate buffer (pH 6.8) containing 1 mM EDTA at 40°C with a flow rate of 1 ml/min. The four nucleotides can be simultaneously assayed within 13 min by monitoring the effluents with a UV detector. It was also indicated that the transhydrogenase activity of spinach FNR can be advantageously assayed by measuring the nucleotides by this method.

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Larvae of the turnip sawfly, Athalia rosae ruficornis, feed exclusively on plants of the family Cruciferae. However, the adult insects are attracted to a Verbenaceae plant, Clerodendron trichotomum, and feed voraciously on its leaf surfaces. Two kairomonal substances that stimulate this feeding behavior were isolated from the leaves of C. trichotomum and identified. They are called clerodendrin B and D. Another substance called clerodendrin A is a major component in the leaves of cC. trichotomum, but it did not elicit a feeding response in the sawfly in spite of its structural similarity to clerodendrin B and D. The ecological functions of these kairomonal substances for the turnip sawfly are suggested here.

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The effects of glycine (Gly) and taurine (Tau) added to diets at a 5% level on plasma and liver lipid levels, fecal bile acid excretion and liver cholesterol 7α-hydroxylase activity were investigated with rats fed on 10% and 25% casein diets containing cholesterol. The effects of Gly and Tau on the hypercholesterolemia induced by methionine and choline chloride were also investigated. The plasma cholesterol-lowering effect of Gly was stronger than that of Tau in the 10% casein diet, but the effect was reversed in the 25% casein diet. Although the hypercholesterolemia induced by methionine was almost completely prevented by Gly, the effect of Tau was limited. The plasma cholesterol-lowering effect of Gly could not be fully explained by the stimulation of fecal bile acid excretion, whereas the effect of Tau appeared to be associated with the fecal bile acid excretion. The addition of Tau significantly increased the cholesterol 7α-hydroxylase activity in all the experiments, while Gly had no effect except for that from the 25% casein diet. These results indicate that plasma cholesterol-lowering effects of Gly and Tau are elicited through different mechanisms.

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Ferredoxin-dependent sulfite reductase (Fd-SiR) (EC 1.8.7.1) was purified about 1136-fold, with a yield of 11%, from fresh thalli of Porphyra yezoensis by a procedure involving ammonium sulfate precipitation, DEAE-cellulose chromatography, Butyl-Toyopearl chromatography, Sephadex G-100 gel filtration and ferredoxin-Sepharose affinity chromatography. The purified enzyme was apparently homogeneous, as judged on polyacrylamide disc gel electrophoresis, with a specific activity of 100 units/mg of protein. The molecular weight of the enzyme was estimated to be 70 kilodaltons by gel filtration. On subunit analysis by SDS-PAGE, a single band corresponding to molecular weight of 65 kilodaltons appeared. The purified enzyme (Fd-SiR) showed 5-times higher ferredoxin-dependent activity than methyl viologen-linked activity. In the oxidized form, the enzyme exhibited absorption maxima at 278, 390 (Soret band), 586 (a band) and 714 (CT band) nm, indicating that siroheme is involved in the catalysis of sulfite reduction. The absorbance ratios, A₃₉₀: A₂₇₈ and A₅₈₆: A₃₉₀, were 0.32 and 0.31, respectively. A plot of the substrate (sulfite) and electron donor (ferredoxin) concentrations versus enzymatic (Fd-SiR) activity yielded sigmoidal curves, giving Hill coefficients (n) of 2.3 (for sulfite) and 2.7 (for ferredoxin), respectively. Antibody against the isolated enzyme was raised in rabbits. Analysis of the antiserum by immunodiifusion suggested that it was specific against isolated Fd-SiR. Using the antiserum, dot immunoblotting was performed to determine the immunological similarity of Fd-SiRs from Porphyra yezoensis, Spirulina platensis, Brassica chinensis and Spinacia oleracea. The tests revealed that the four forms of assimilatory Fd-SiR have antigenic determinants in common.

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Nucleoside oxidase, a novel nucleoside oxidizing enzyme has been purified from a crude extract of Pseudomonas maltophilia LB-86 by a ammonium sulfate fractionation, heat treatment, column chromatography on DEAE-Toyopearl, and gel filtration twice on Sephacryl S-200. The overall purification was approximately 60-fold with a yield of 35%. The purified enzyme gave a single protein band on acrylamide gel electrophoresis.
Reaction products from inosine were identified as inosine-S'-aldehyde and inosine-5'-carboxylic acid. The enzyme catalyzed the oxidation of inosine to inosine-5'-carboxylic acid via inosine-5'-aldehyde using molecular oxygen as a primary electron acceptor with no formation of hydrogen peroxide.

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Nucleoside oxidase purified from Pseudomonas maltophilia LB-86 had mol. wt. = 130.000 and was composed of one each of four non-identical subunits: subunit α, 76, 000; subunit β, 33, 000; subunit γ, 18, 000; subunit δ, 14, 000. The enzyme contains 1 mol of covalently bound FAD, 2 g atoms of non-heme iron, 2 mol of labile sultides, and 1 mol of heme per mol enzyme protein. The absorption spectrum of nucleoside oxidase had maxima 278 and 390 nm, and shoulders at 343 and 450 nm.
The enzyme catalyzes the oxidation of various nucleosides, and the Km value for inosine was 4.4 × 10^-5 M. The enzyme was most active at pH 5-6, and was most stable between pH 5.0-6.0 and at temperatures below 60°C. The activity was strongly inhibited by N-bromosuccinimide and potassium cyanide.

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Growth hormone (GH) was purified from pituitary glands of tuna (Thunnus albacares). The yield of this hormone was 4mg/g wet tissue. The hormone had a molecular weight of 21, 000 and an isoelectric point of 7.1. The partial amino acid sequence including N-terminal Gin, which was modified to pyroglutamate, was established by analyzing peptide fragments generated by chemical and enzymatic treatments. Intraperitoneal injection of tuna GH at doses of 0.1 and 1 μg/g body weight at 7 day intervals resulted in a significant increase in body weight and length of juvenile rainbow trout (Salmo gairdneri). The GH-treated fish had a 3-fold higher growth rate and a 1.6-fold higher food conversion efficiency than the control fish.

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A malonyl-CoA-dependent, acyl carrier protein (ACP)-non-requiring fatty acid elongation system was isolated from Mycobacterium avium. Chromatographical fractionation and reconstitution studies indicated that the system is composed of separable protein components like a fatty acid elongation system from M. smegmatis reported previously. In comparison of the two systems, however, some distinct features were observed in pyridine-nucleotide-coenzyme requirements and in sensitivities to isoniazid (N-amino-3-pyridine carboxylic acid amide); the system from M. avium used NADPH as a sole hydrogen donor and was inhibited by the agent, in vitro, at the concentration of 2mM, while the agent has been proved to have no inhibitory effect on the system from M. smegmatis which required both NADH and NADPH. Using the fractionated component enzymes of the system from M. avium, similar concentrations of isoniazid were found to be distinctly inhibitory against 3-oxoacyl-CoA reductase and more slightly against enoyl-GoA reductase with Ki values of 352.8 μM and 5.5 mM, respectively.

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