The combined use of a lytic enzyme complex of Bacillus circulans WL 12 and a detergent, Emulgen 120, caused effective reduction of the minimal inhibitory concentrations of the fungicides, Polyoxin B and Kitazin P, for Pyricularia oryzae. For Glomerella cingulata and Alternaria kikuchiana, the further addition of Novozym 234 or the crude enzyme from Streptomyces sp. was necessary for the same effect.

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Iron absorption from iron-saturated lactoferrin was compared to that from ferrous sulfate in iron-deficient anemic rats. One group of rats was given 50 μg of iron orally once a day and changes in red blood cell density, hematocrit, and hemoglobin values were measured at 14-day intervals for 70 days. A statistically significant increase in these values was demonstrated for the rats fed ironsaturated lactoferrin (50 μg Fe/35mg lactoferrin/day), while the ferrous sulfate group showed no improvement in these values. The results suggest that iron from iron-saturated lactoferrin is absorbed across the intestinal mucosa by a mechanism other than the one by which soluble iron salts are absorbed.

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The effect of sorbitol treatment on the cell structure of Candida boidinii No. 2201 was studied by transmission electron microscopy (TEM). The high ATP-producing activity of the cells was proved to be due to the plasmolysis without destruction of essential organelles for the ATP-producing system.
To prepare active cells constantly, the essential elements of the yeast extract in the culture medium were identified: biotin was an essential growth factor; Fe²⁺ and thiamine stimulated more or less the growth; and Zn²⁺ strongly stimulated the growth. Limitation of Zn²⁺ in the culture medium (0.5mg/l of ZnCl₂) improved the ATP yield from AMP, the conversion rate being 92%, possibly due to repression of AMP deaminase, for which Zn²⁺ was a cofactor and which affected the ATP-producing activity.
A Zn²⁺ -supplemented culture provided fully-active cells as to ATP production. TEM revealed that Zn²⁺ was a necessary factor for the formation of peroxisomes in which alcohol oxidase and catalase were localized.

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The optical isomers (R)-(-)- and (S)-(+)-tetrahydro-4-fluoromethyl-4-hydroxy-2H-pyran-2-one (fluoromevalonolactone, . FMev) of the insect anti-juvenile hormone were synthesized by using combined enzymatic and chemical methods, and their biological activities were examined by using the silkworm Bombyx mori L. It was found that the observed anti-juvenile hormone and insecticidal activity against Bombyx mori after topical treatment with racemic FMev was due to the (R)-(-)-enantiomer of FMev, the (S)-(+)-enantiomer being inactive.

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The modes of action of three thermostable endo-xylanases (Xn-A, Xn-B, and Xn-C) from the mesophilic fungus strain Y-94 on Xylooligosaccharides and their alditols (DP 2-8) were studied. Non of the enzymes could hydrolyse xylobiose. Oligosaccharides upwards from xylotetraose were immediately hydrolysed by the endo-xylanases, but xylotriose was slowly hydrolysed. Xn-A hydrolysed xylotriose more slowly than the other two. From the dependency of the molecular activity (ko) on the chain length of the substrates, it was suggested that the three xylanases had the same subsite size (5 xylose units). Analysis of the frequency distribution of bond cleavage of oligosaccharide-alditols showed that no enzymes could attack the first bond from the non-reducing end of oligosaccharides. The other bonds were hydrolysed by these enzymes by endo-type action. The action pattern for xylopentaitol suggested that the catalytic site was located between the second and third subsite from the non-reducing end, since the substrate was mainly hydrolysed to xylobiose and xylotriitol.

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The injection of live or heat-killed bacteria into larvae of trie silkworm, Bombyx mori, induced antibacterial activity in the hemolymph. A wide variety of gram-negative and gram-positive bacteria were effective as inducing agents, but saline alone, yeast cells and fungal spores were not effective. The antibacterial activities were separated into six bands on native polyacrylamide gel electrophoresis, which were sensitive to trypsin. Some of these antibacterial proteins were partially purified by CM-cellulose column chromatography. The proteins were heat-stable and showed no lysozyme activity. The proteins repressed the growth of various gram-positive and gram-negative bacteria.

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Three lytic enzymes, C-2, C-4 and C-5, capable of lysing cells of Rhodococcus erythropolis AN13 were purified from the cultural filtrate of Flavobacterium species SH-548 by (NH₄)₂SO₄ fractionation and column chromatographies on CM-Toyopearl and SP-Sephadex. The three purified enzymes gave single protein bands on polyacrylamide gels. C-4 and C-5 were stable between pH 3.0 and 12.5, and C-2 between pH 5.5 and 11.0. The molecular weights of C-4 and C-5 were 26, 000 and that of C-2 was 36, 000, -as judged on sodium dodecylsulfate-polyacrylamide gel electrophoresis. C-4 and C-5 also showed proteolytic activity toward casein, but C-2 did not exhibit such activity. C-2 showed higher specific lytic activity toward cells of R. erythropolis AN-13 than C-4 and C-5.

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The application of ethephon (ETP), an ethylene generating chemical, to press-injured rice leaves induced PAL (EC 4.3.1.6) activity. This induction disappeared when the concentration was low. A Scatchard plot for ligand binding gave a linear relationship between the PAL reaction rate at the time for the maximum rate of induction (t_m) along the sigmoidal progress and the ratio of the PAL reaction rate versus ETP in a specific range of concentration. A similar application of glutamate (Glu) induced PAL activity, and the application of 1-aminocyclopropane-l-carboxylic acid (ACC) also induced PAL activity. The induction of rice leaf PAL with Glu was inhibited in the presence of tiron (TR), a superoxide scavenger, was weakly inhibited with aminooxyacetic acid (AOA), but was not inhibited with abscisic acid (ABA). The induction with ACC was also inhibited in the presence of TR, was weakly inhibited with AOA, and further was weakly inhibited with ABA. The inoculation of blast fungus conidia or application of fungal proteoglucomannan (RIF) to press-injured rice leaves induced PAL activity. The induction proceeded along sigmoidal curve accompanying the distinct auto-inactivation phase. Each approximated t_m (midpoint of an individual sigmoidal curve) was determined; t_m = 2.4hr with an incompatible race, t_m = 5.3 hr with a compatible race, and t_m= 11.0 hr with RIF stimulation. The 3 inhibition profiles of TR, AOA and ABA upon rice leaf PAL induction either with inoculation or with stimulation were quite similar to the inhibition profiles upon PAL induction with Glu.

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In order to develop a fermentation process for lactase (β-D-galactosidase) production, we selected an excellent lactase producer, Kluyveromyces lactis. KY 5466, from our yeast culture collection. Some of its mutant derivatives which formed a blue pigment from 5-bromo-4-chloro-3-indolyl-β-D-galactoside in the presence of glucose and those which assimilated phenyl-β-Dgalactoside as a carbon source produced 2 to 2.7 times as much lactase as the parent strain. In the late stage of cultivation, the lactase activity decreased to zero for all strains tested soon after the complete consumption of sugar. This phenomenon was found to be correlated with a decrease in the efficiency of protein extraction from the cells. The maximal amount of lactase produced reached 155 units per ml at 48 hr in a 5-1 jar fermentor culture with sugar feeding.

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Two enzymes, a nutlease and a ribonuclease (RNase) were isolated from the cell walls of potato tubers. The nuclease was purified by 1370-fold fractionation with ammonium sulfate and chromatography on Sephadex G-200 and DEAE-Sephadex A-50 columns. The purified nuclease hydrolysed both RNA and DNA, yielding primarily purine 5'-nucleotides. The ribonuclease did not cleave DNA and the hydrolysis of RNA produced 2':3'-cyclic nucleotides as products. Both enzymes were inhibited by Cu²⁺ and Zn²⁺, while EDTA inhibited the nuclease and promoted the RNase. The cell wall enzymes are different from the corresponding cytoplasmic enzymes previously characterized [T. T. Nguyen, M. M. Palcic and D. Hadziyev, J. Chromatogr., 388, 189 (1987)] with respect to pH and temperature optima and molecular weights.

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Hen egg ovalbumin i a mixture of three kinds of proteins, A₁, A₂, and A₃ with two, one, and no phosphoryl residues, respectively. These three proteins were obtained by acid phosphatase treatment and then chromatography on a DEAE cellulofine AH column. The isoelectric points of A₁ A₂, and A₃ were found by isoelectric focusing to be pH 4.75, 4.89, and 4.94, respectively. The denaturation temperature of each protein was examined by differential scanning calorimetry at its own isoelectric point and at pH 4.65. At both pHs, A₃ had a lower denaturation temperature than A₂ or A₁. The surface tension of an A₃ solution reached a constant more quickly than A₁ or A₂ after formation of a new surface of the solution. These results indicate that the completely dephosphorylated ovalbumin A₃ is more susceptible to heat and surface denaturation than phosphorylated ovalbumin is. The difference in the heat aggregation patterns of A₁, A₂, and A₃ solutions at different pH or salt concentrations showed that the electrostatic-repulsive force is important in helping to prevent the random aggregation of denatured ovalbumin.

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Natural okadaic acid 1 was transformed into the 7, 24, 27-tri-0-benzyl-l, 2-acetonide derivative (4) in a 66% overall yidd. The corresponding synthetic derivative (4) was identified with this authentic sample.

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A new hybrid promoter, "pac", comprising the '-35' region of the bacteriophage T5 P25 gene promoter and the '-10' and the operator regions of the lacUV5 promoter, was chemically synthesized and used to construct a new expression vector. The activity of the hybrid promoter was compared with that of the tac (trp: lac fusion) promoter, which is widely used as a strong and controllable promoter. The activity of the pac promoter was found to be stronger by about 3-fold than that of tac when assayed with the chloramphenicol acetyltransferase (CAT) system. The pac promoter, however, was not repressed as efficiently as the tac promoter

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Aliphatic bisenals (1a-n), ω-hydroxydienals (2a-n), ω-hydroxy-2-alkenals (3a-d), vinylketones (4a, b), an enon-enal (4c) and three geometric isomers of aliphatic bisenones (5a-g) were synthesized in order to study the relationship between the structure and microbicidal activity.

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The growth-inhibition activity of 2-alkenals (1a-h), bisenals (2a-o), ω-hydroxyalkadienals (3a-o), ω-hydroxy-2-alkenals (4a-e), an enon-enal (5a), bisenones (5b-h) and vinylketones (6, 7) against Rhodotorula gracilis was compared. In the case of the bisenals and bisenones, enhanced activity compared with the monoenals (1a-g) and vinylketones (6, 7), respectively, was observed. Both compounds showed growth-inhibition activity when the space between the carbon atoms with a formal positive charge was equivalent with thirteen to fifteen or sixteen carbon atoms. In the case of ω-hyldroxyalkadienals, higher activity than that of the monoalkenals (1a-g) and ω-hydroxy2-alkenals (4a-e) was observed. The reason for these results are discussed.

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Four stereoisomers of methyl 4, 6-di-O-D-glucopyranosyl-β-D-glucopyranosides, in which the H-6proS proton at the (1→6)-linkage moiety was selectively replaced by a deuterium (²H), were synthesized through the photobromination of 1, 6-anhydro-per-O-acetyl-β-D-maltopyranose and β-D-glucose, with subsequent deuteride reduction of the brominated products (C-6exo bromides) by tri-n-butyltin deuteride. The chirally deuterated sugars enabled us to differentiate the H-6proR and H-6proS signals at the (1→6)-linkage moiety and, thereby, to clarify the conformational distributions about the C5-C6 bonds.

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2-Hydroxy-l-phenyl-l, 4-pentanedione (HPP) was isolated and identified from Pharbitis purpurea as a flower-inducing substance by using Lemna paucicostata 151 as a bioassay plant. This compound was racemic and was found to be an artifact, which could be formed by condensation between acetone and phenylglyoxal. Phenylglyoxal was shown to be naturally occurring in P. purpurea and also had flowering activity. The activity of each compound was inhibited by GA₃, ABA and IAA, and promoted by zeatin in L. paucicostata 151, as in the case of benzoic acid-related compounds.

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The hydrophobicities of ricin D and its constituent polypeptide chains (A- and B-chains) were studied quantitatively. Fluorometric studies using cis-parinaric acid as a probe indicated that the A-chain had 4 times the "surface hydrophobicity" of the B-chain, and the "surface hydrophobicity" of ricin D was lower than that of the B-chain. Density gradient ultracentrifugal analyses using [³H]Triton X-100 indicated that about 300 mol of Triton X-100 were bound per mole of the A-chain in the absence and presence of sodium dodecyl sulfate (SDS), while there is no binding of Triton X-100 to the B-chain in the absence of SDS but 60 mol of Triton X-100 were bound per mole of the B-chain in the presence of 0.02% SDS. No measurable amount of Triton X-100 was bound by ricin D even in the presence of 0.02% SDS. From these findings, it was suggested that the A-chain had larger fractions on its surface which were capable of hydrophobic interaction than the B-chain, and these fractions were masked in the ricin D molecule owing to the interfacial contact of the A- and B-chains. The significance of the high hydrophobicity of the A-chain in the function of ricin D is also discussed.

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Feeding with a 3.5% histidine diet caused hypercholesterolemia, hepatomegaly and decreased lipid content in the liver of rats. The addition of 1.0% L-methionine to the 3.5% histidine diet caused increases in liver lipids and serum total cholesterol as compared with those in rats fed with the 3.5% histidine diet. The addition of 1.0% L-cystine to the 3.5% histidine diet caused an increase in serum total cholesterol compared with that in rats fed with the 3.5% histidine diet, but the addition of taurine had no effect on serum and liver lipids. The addition of 2.5% or 5.0% glycine to the 3.5% histidine diet decreased serum total and HDL cholesterol compared with that in rats fed with the 3.5% histidine diet.

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cDNA clones which include the coding sequences of chum salmon prolactin (sPRL) have been isolated from a cDNA library prepared from chum salmon pituitary gland poly(A)⁺ RNA. A synthetic oligonucleotide probe based on amino acid residues 122 - 127 of sPRL was used as a hybridization probe to select recombinant plasmids carrying the sPRL coding sequences. One of the cDNA clones, which includes the longest cDNA insert, has been sequenced. The cDNA sequence codes for a polypeptide of 210 amino acids, including a putative signal sequence of 23 amino acids. The deduced amino acid sequence of the mature region matched that of the sPRL polypeptide isolated from chum salmon pituitaries (ref. 1). sPRL cDNA was expressed in Escherichia coli under the control of the E. coli trp promoter. sPRL was identified by Western blotting using rabbit antiserum to authentic sPRL.

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The bio-antimutagenic potential of benzaldehyde and its derivatives was investigated on mutagenesis induced by 4-nitroquinoline 1-oxide (4NQO) in Escherichia coli WP2s uvrA trpE. Benzaldehyde and 18 kinds of hydroxy-, methoxy-, or ethoxybenzaldehydes other than 3, 4-diethoxybenzaldehyde decreased the induced mutation frequency by 42 to 91%. Among these compounds, strong bio-antimutagenic effects were observed for vanillin (3-methoxy-4-hydroxybenzaldehyde), vanillal (3-ethoxy-4-hydroxybenzaldehyde), protocatechualdehyde (3, 4-dihydroxybenzaldehyde), 2, 5-dimethoxybenzaldehyde, o-anisaldehyde (o-methoxybenzaldehyde), and m-anisaldehyde. On the other hand, benzyl alcohol or benzoic acid analogues such as vanillyl alcohol, vanillic acid, isovanillic acid, and veratric acid did not show any bio-antimutagenic effects. These observations suggest that the aldehyde radical is important for bio-antimu'tagenic activity.

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A bacterium was isolated from the homogenate of Protogonyaulax tamarensis cells cultured in T1 medium containing antibiotics. The culture broth after centrifugation, to remove the cells, and the bacterial cells contained a toxin that could kill mice with signs similar to those of poisoning by paralytic shellfish toxins or tetrodotoxin. The toxin in the cultured broth was identified as saxitoxin by TLC, HPLC and electrophoretic analyses.

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Methanol extracts of dried stem bark of Cocculus triolobus DC showed significant phytotoxic activities toward seeds of barnyard grass, leaf mustard and cucumber. Aristolochic acid (I) and aristolic acid (II) were isolated and identified as the active principles.

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In an HPLC analysis of vitamin B₆ derivatives, the use of a reversed-phase ODS column in conjunction with a fluorescence detector has given promising results. However, PLP was rather insensitive to the analysis, making it difficult to obtain accurate results, especially in biological materials. Subsequently, a pre-column treatment that involved extracting the sample solution with 1 M perchloric acid, heating the extract for 3 hr at 50°C in the presence of 5mM KCN at pH 7.5, and then allowing it to stand for 24hr at room temperature served to overcome difficulties in the analysis. The fluorescence enhancement of PLP was over 10-fold and produced a single peak that was applicable to the quantification of PLP in biological materials.

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A novel arseno-sugar was isolated from the brown alga Sargassum thunbergii. Instead of the dimethylarsinoyl group reported for algal arseno-sugars, this has a trimethylarsonium group, which is borne by arsenobetaine, a ubiquitous organoarsenic compound in marine animals. This may be an intermediate between arseno-sugars and arsenobetaine.

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