An alkalophilic actinomycete, strain OPC-15, which was isolated from a soil sample, produced phenazine antibiotics in the mycelium. From the results of taxonomic studies, this strain was designated as Nocardiopsis dassonvillei OPC-15. N. dassonvillei OPC-15 produced different phenazine antibiotics under different culture conditions (incubation period, incubation temperature and temperature shift). 1, 6-Dihydroxyphenazine (III) was obtained from the mycelium on incubation for 6-8 days at 27°C, while 1, 6-dihydroxyphenazine 5, 10-dioxide (I, iodinin) was isolated on incubation for 6 days at 27°C followed by further incubation for 2 days at 4°C.
1, 6-Dihydroxyphenazine 5-monooxide (II) was purified from the mycelium cultured under both these two sets of cultural conditions. These results suggest that the N-oxidation of III was catalyzed enzymatically with the temperature shift from 27°C to 4°C.

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Lunatoic acid A and (-)-mitorubrinic acid have been isolated as chlamydospore-like cellinducing substances from Cochliobolus lunatus. (+)-Sclerotiorin, (+)-rotiorin, citrinin and sclerin were shown to have the same activity. Although they share no common structural feature, all these active substances react with methylamine. The reaction products do not have this activity. The reaction curves showed a positive correlation between the chemical reactivity of chlamydospore-like cell-inducing substances with methylamine and their biological activities.

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When Escherichia coli B growing logarithmically in minimal medium was stressed suddenly by 0.5M NaCl, intracellular levels of K⁺ and amino acids (peptides) increased temporarily in that order. But betaine and proline levels were very low and scarcely increased. The increased levels decreased with the resumption of growth. In complex medium, intracellular levels of K⁺, betaine, proline, and other amino acids (peptides) increased in that order; when betaine and proline were present in the medium, the cells accumulated these solutes during stress. The increased levels of K⁺, proline, and other amino acids (peptides) also decreased with the resumption of growth. In contrast with those solutes, betaine level increased continuously and contributed to adjusting the turgor pressure. The cells had the same osmoregulative function regardless of proline level in the cell, and further, osmotolerance under limited K⁺ level declined considerably.

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The osmoregulatory role of amino acids and inorganic ions was studied in Plantago japonica Franch. et Sav., Which was grown on vermiculite irrigated with increasing salinity, as well as in samples collected from sandy beaches along the Sea of Japan. The amino acid contents increased with increasing salinity. In particular, arginine, which is originally present at high levels in the crowns, together with asparagine and glutamine, increased considerably, but the proline content in the plant was low and did not seem to function to regulate turgor pressure. Increasing the salinity of the medium revealed the capacity of the plant to increase chloride, potassium, and sodium ions in the tissues, and to a lesser extent, magnesium, calcium, and phosphate contents. The solute levels in leaves, calculated as the sum of the content found in the extract, matched closely the external osmolarity in the medium. Other ions or compounds may also be involved in the osmoregulation in this plant, particularly in the roots. Sugars, glycerol, citric acid (and other common organic acids) and putrescine did not seem to be involved in the osmoregulation.

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Human pro-urokinase cDNA was isolated from the cDNA library constructed from human kidney mRNA using the dC/dG homopolymer tailing method and Okayama-Berg method with pBR322 as a vector. A mature polypeptide starting with Ser was produced in Escherichia coli under the control of the tac promoter and the Shine-Dalgarno sequence of the catechol 2, 3-oxygenase gene derived from Pseudomonas putida. By replacing the sequence coding for N-terminal eight amino acids of pro-urokinase with the synthetic DNA oligomer, the bacterial pro-urokinase had a molecular weight of 47, 000 daltons and accounted for 15% of the insoluble fraction of E. coli proteins in induced cells. Its biological activity was restored by renaturing the bacterial product. The activity of bacterial pro-urokinase was 450 IU/ml culture.

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Protoplast fusion was studied to breed a koji-mold, Aspergillus awamori var. kawachi, used for making a Japanese spirit, shochu. Protoplasts were obtained from mycelia of two biochemical mutants using an enzyme system from Trichoderma viride consisting of mainly β-1, 3-glueanase and chitinase. Approximately 10-20% of these protoplasts regenerated on a solid culture medium with a soft agar overlay. When the two types of protoplasts were treated with a fusogen including 35% polyethylene glycol, they fused effectively and formed a heterokaryon. A strain obtained from the hetrokaryon using d-camphor showed high stability (98.8%) and numerical sporulation, and produced the same levels of amylase and citric acid as those by the original strain. From these results and the formation of recombinants, the new strain was assumed to be a heterozygous diploid. The appearance frequency of the diploid was 2.9 × 10^-2. The existence of a parasexual cycle in this fungus was also discovered, using the protoplast fusion technique.

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Modulation of a pyridoxal 5'-phosphate-synthesizing enzyme, pyridoxine (pyridoxamine) phosphate oxidase (EC 1.4.3.5), was investigated in wheat suspension culture. Pyridoxine-HCl added to the culture medium enhanced the pyridoxine 5'-phosphate (PNP) oxidase activity, but not pyridoxamine 5'-phosphate (PMP) oxidase activity. Thiamine-HCl also showed a similar effect. The PNP oxidase activity was most effectively enhanced by potassium nitrate from 40 to 80 mM, which was added to the culture medium as a nitrogen source. On the other hand, PMP oxidase activity was stimulated by ammonium-type nitrogen.

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Carbohydrate metabolism during Sporulation in spheroplasts of Saccharomyces cerevisiae was examined to detect changes in the synthesis and degradation of cellular materials. The cellular materials in spheroplasts were fractionated into extraspore material, spore-cytoplasm and spore walls. Glycogen in the extraspore material was synthesized early in development and was degraded prior to spore maturation. Trehalose, glycogen and mannan in the spore-cytoplasm were all synthesized during spore formation. Glucan, as a major component of the spore walls, was synthesized during spore formation. A glucosamine polymer, as a component of the outer layers of the spore walls, was synthesized immediately after incubation in the Sporulation medium. Mannan synthesis, as a minor component in the spore walls, was completed prior to spore maturation.

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A new enzyme reactor system for low-molecular-weight substrates, utilizing forced flow through an enzyme-immobilized membrane, was developed. Invertase was physically immobilized within a porous ceramic membrane by filtering an enzyme solution, and a sucrose solution was forced through the membrane by pressure, using a crossflow filtration method. The reaction rate of the forced-flow system was more than 10 times greater than that observed in a diffusion-controlled system. The reaction rate in both systems was mathematically modeled, and the simulated results were in good agreement with the experimental results. The reaction rate in the forced-flow system was easily controlled by pressure, and its productivity was greater than those reported in other reactor systems.

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The structures of eight novel triterpenoids, ganoderiol C (1), D (2), E (3), F (4), G (5), H (6), I (7), and ganolucidic acid E (8), isolated from the fruiting body of Ganoderma lucidum were determined by spectroscopic methods. In addition, the absolute configuration at C-23 of ganolucidic acid D (9) was determined from the CD spectrum of its p-dimethylaminobenzoate derivative.

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Ferredoxin-sulfite reductase (Fd-SiR) [hydrogen-sulfide: ferredoxin oxidoreductase, EC 1.8.7.1] from a cyanobacterium, Spirulina platensis, has been purified to homogeneity by a novel procedure. Subunit analysis by sodium dodecyl sulfate gel electrophoresis yielded a single protein band with a molecular weight of 63, 000. In the presence of 0.1 M potassium sulfate, gel filtration produced a value of 120, 000, indicating the presence of a dimer in this ionic environment. A plot of ferredoxin concentration versus enzymatic (Fd-SiR) activity yielded a sigmoidal curve, giving a Hill coefficient (ñ) of 2.2. Purified Fd-SiR, in the oxidized form, has absorption maxima at 279, 388, and 590 nm. Thus the enzyme has the properties of a siroheme-containing protein.

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Autoclaved mycelium of Aspergillus oryzae Y-2-32 adsorbed melanoidin, especially lower molecular weight fractions, and the degree of the adsorption was influenced by the kind of sugars utilized for growth.
The melanoidin-adsorbing ability of mycelia was repressed by a high concentration of salt. Furthermore, it decreased to half the initial level on washing with a 0.1% Tween 80 solution and was entirely lost on washing with a 0.1% sodium dodecylsulphate solution.

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The screening of filamentous fungi having the ability to decolorize molasses pigments was performed in Thailand, and some strains, belonging mainly to the class Deuteromycetes, were selected from among a total of 228 strains. Of these, nine showed decolorization yields of more than 50%, and they required different culture conditions, such as the glucose concentration, medium pt[ and nitrogen sources, for a high decolorization yield, respectively.
The isolated strain, D90, showed the highest decolorization yield (about 93%) wfhen it was cultivated at 30°C for 8 days in a molasses pigment solution containing glucose 2.5%, yeast extract 0.2%, KH₂PO₄ 0.1% and MgSO₄•7H₂O 0.05%, the pH being adjusted to 6.0. This potent strain was identical with the order Mycelia Sterilia due to the following characteristics, septate hyphae formation and no clamp connections or spores.

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Three kinds of molasses waste water were collected from the stillage of an alcohol factory, and an anaerobic and an aerobic pond of its waste water treatment plant, respectively, and their chemical properties, such as chemical oxygen demand value, biological oxygen demand value and so on, were examined in this study.
Mycelia Sterilia D90 decolorized about 90% of the molasses pigment in 10 days and at the same time caused an about 80% decrease in the biological oxygen demand value when glucose 2.5%, NaNO₃ 0.2%, KH₂PO₄ 0.1% and MgSO₄•7H₂O 0.05% were added to the molasses waste water from the stillage as nutrients. But without supplementation of the nutrients, the decolorization yield was only 17.5%. Furthermore, this strain showed a decolorization yield of about 70% in 11 days and caused a decrease in the biological oxygen demand value of about 90% in 15 days under non-sterile conditions.
In the fed-batch system, this strain showed a constant decolorization yield of about 80% and caused a decrease in the biological oxygen demand value of about 70% during three times replacement (24 days).

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Bacillus subtilis 2633 hyperproduced α-amylase (about 3000-fold amount of the parental strain, B. subtilis 6160). An α-amylase gene of B. subtilis 2633 was cloned into Escherichia coli using a B. subtilis-E. coli shuttle vector, pHY300PLK. When the recombinant plasmid pAM26 containing the α-amylase gene was introduced into B. subtilis 6160, a transformant produced about 40, 000 U/ml of α-amylase, which is 4000 times that of B. subtilis 6160. This indicates that the α-amylase gene (amyR-amyE) of 2633 has hyperproducing activity in itself. The nucleotide sequencing of the promotor region and comparison with those of other B. subtilis strains suggested that several differences in the nucleotide sequences upstream from the transcription initiation site could be responsible for the α-amylase production. Southern blot analysis showed that B. subtilis 2633 contains several copies of the α-amylase gene, which should also contribute to the hyperproductivity.

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Two starch phosphorylases, P-1 and P-2, were purified from pollen grains of Typha latifolia Linne. The purified P-1 was homogeneous on polyacrylamide gel electrophoresis and its molecular weight was 112, 000 by SDS-polyacrylamide gel electrophoresis. Both enzymes had optimum pHs of 5.5-5.8 in the direction of Pi release and of 7.3-8.0 in the direction of G-I-P formation. In both directions, the two enzymes had similar activities for soluble starch and amylose, but a definite difference of activity for starch granules from the pollen was observed; P-1 showed a high activity, comparable to those for other substrates, while the activity of P-2 was very low in the direction of Pi release. P-1 had higher Km values for amylose, maltoheptaose, and maltopentaose in both directions than P-2 did.

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The extracellular cholesterol oxidases produced by an inducible mutant, U-S-A-18, and a constitutive mutant, U-S-3011, of Arthrobacter simplex were purified 18.9- and 15.2-fold as to specific activity, respectively, from the fermentation broth through successive purification steps involving DEAE-cellulose column chromatography, ultrafiltration and gel filtration on Sephadex G-75. The overall yields of the purified enzymes were 28% and 40%, respectively. Both the purified enzymes were confirmed to be homogeneous, and the molecular weights of both enzymes were estimated to be 57, 000 on gradient SDS-polyacrylamide gel electrophoresis. Both the enzymes were stable in the pH range of 6 to 10 at 30°C for 2hr. The optimal pH and temperature for both enzymes were found to be 7.5 and 50°C, respectively. The Km values of the enzymes were 28.4 μM and 30.8 μM, respectively, when cholesterol was the substrate. The activities of both enzymes were remarkably stimulated by Triton X-100 and partially inhibited by sulfhydryl reagents. Due to the similarities of the properties of the two enzymes, it is concluded that the inducible and constitutive cholesterol oxidases produced by the mutants, U-S-A-18 and U-S-3011, are similar in nature.

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D-Sorbitol (sorbitol) production from D-glucose could be achieved by initial isomerization of D-glucose to D-fructose via xylose isomerase, then reduction to sorbitol via sorbitol dehydrogenase coupled with NADH regeneration from the methanol oxidative enzymes system by an intact cell system of a methanol yeast, Candida boidinii (Kloeckera sp.) No. 2201. Sorbitol dehydrogenase was purified 351-fold from a cell-free extract of o-xylose-grown cells and characterized. It oxidized preferably D-mannitol besides sorbitol, and reduced preferably D-xylulose and D-ribulose, besides D-fructose. Km values for sorbitol and D-fructose were 7.7 and 263 mM, and V_max values were 301 and 384μmol/min/mg, respectively. The enzyme activity was strongly stimulated by Fe³⁺ and significantly inhibited by Pb²⁺, EDTA, and o-phenanthroline.

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A proteolytic, marine luminous bacterium was isolated from seawater and identified as Vibrio splendidus biotype I strain FLE-2. A proteinase from this strain, with a specific activity 21-fold higher than that of the culture supernatant, was purified to homogeneity. The purified enzyme had a molecular weight of 50, 000. The enzyme was most active at pH 8.0 and 55°C, and stable below 35°C. The enzyme activity was completely inhibited by EDTA, orthophenanthrolin and phosphoramidon. Also metal ions such as Cu²⁺, Hg²⁺, Ni²⁺, Cd²⁺ and Co²⁺ inhibited the activity. These results indicate that this enzyme is a metal-chelater-sensitive, alkaline proteinase.

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A proteolytic, marine luminous bacterium was isolated from seawater and identified as Vibrio harveyi strain FLA-11. A proteinase from this strain, with a specific activity 61-fold higher than that of the culture supernatant, was purified to homogeneity. The purified enzyme had a molecular weight of 84, 000, comprising a tetramer of 21, 000 molecular weight subunits. The enzyme was most active at pH 8.0 and 55°C, and stable below 40°C. The enzyme activity was completely inhibited by EDTA, orthophenanthrolin and phosphoramidon. Metal ions such as Cu²⁺, Hg²⁺, Ni²⁺, Cd²⁺ and Co²⁺ also inhibited the activity. These results indicate that this enzyme is a metal-chelatersensitive, alkaline proteinase.

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Three α-amylases that produce maltohexaose as the main product from starch were found in a culture filtrate of alkalophilic Bacillus sp. H-167, which was isolated from soil. The optimum culture conditions for enzyme production were determined: initial medium pH 9.4; temperature, 37°C; and 50-60 hr cultivation under aerobic conditions. The enzymes were separated completely and purified to be homogeneous on disc electrophoresis by using chromatographies on DEAE-Toyopearl 650M and DEAE-Sepharose CL-6B, followed by gel filtration on Sephadex G-100 or Ultrogel AcA-34. All the enzymes produced maltohexaose in the early stage of hydrolysis, the maximum yield being 25-30%.

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It was found that a mutant strain, K₃-15, of Flavobacterium sp. 238-7 excreted menaquinone (MK) into culture medium supplemented with a detergent. Among 174 kinds of detergent tested, a nonionic detergent, Rikanon UA 5012 (polyoxyethylene oleyl ether), showed the highest ability as to induction of MK excretion into the medium without inhibiting cell growth. MK-4, which was newly formed in cells of the mutant strain, was selectively excreted into the medium, but MK-6, which was the original MK of the wild type strain, was hardly excreted. In the presence of 0.05% Rikanon UA 5012, the MK-4 productivity increased about 20% compared to that without the detergent, and the total amount of MK was 39 mg/1 of culture broth.

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In order to re-examine the effects of reduced citrate synthase activity (designated as CS^L) and feedback-resistant phosphoenolpyruvate carboxylase (PC^R) on the lysine productivities of mutants with feedback-resistant aspartokinase (AK) (AK^R), six AK^R lysine producers were derived from Brevibacterium flavum No. 15-8 with the CS^L and PC^R characters and isolated as mutants resistant to S-(2-aminoethyl)-L-cysteine plus threonine on the medium containing acetate plus pyruvate as carbon sources. These mutants produced more than 40 g/1 of lysine as its HC1 salt in the medium containing 10% glucose. In particular, strain No. 664-7 with normally active and completely feedback-resistant AK produced 45 g/1 of lysine, whereas an AK^R lysine producer, FA1-30, derived directly from wild strain No. 2247 produced only 20 g/1 at maximum.
A homoserine dehydrogenase-defective (HD^-) mutant, H-3-4, with the CS^L and PC^R characters also showed higher lysine productivity, 41 g/1, than an HD^- mutant, H1013, which was derived directly from the wild strain and produced 35 g/1 of lysine.
From the above results, it was concluded that the CS^L and PC^R characters were effective for enhancement of the lysine productivities of both AK^R and HD^- type producers.

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The new selective acylanilide herbicide, MT-5950 [N-(3-chloro-4-isopropylphenyl)-2-methylpentanamide], was found to be a potent inhibitor of photosystem II (PS II) in photosynthesis. It was not as effective as atrazine in increasing variable fluorescence of wheat leaves dipped in herbicide solutions. However, in assays in which absorption across the leaf cuticle did not play a role, MT-5950 was about 10-fold more effective than atrazine in inhibiting the PSII activity of all the species tested. For example, the I₅₀ values of MT-5950 and atrazine for inhibiting linear electron transport in broken chloroplasts of spinach were 0.08 and 0.8 μM, respectively. Atrazineresistant biotypes of Brassica napus and Solanum nigrum were about 10-fold and < 2-fold less susceptible, respectively, to MT-5950 than were susceptible biotypes of the same species as measured by DCPIP photoreduction and CO₂-dependent oxygen evolution. However, MT-5950 was equally as effective as atrazine in competing for ¹⁴C-labeled atrazine from thylakoid proteins. We conclude that MT-5950 inhibits PS II by binding the quinone-binding 32 kD protein at a site that overlaps the binding site of atrazine, but does not significantly overlap that portion of the atrazine binding site that, when modified, confers atrazine resistance.

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For investigation of the biosynthetic pathway of bombykol ((10E, 12Z)-10, 12-hexadecadien-1-ol, the female sex pheromone of the silkworm moth), some ¹⁴C-labelled compounds were applied to pheromone glands of 1-day-old virgin female moths 4hr after lighting (25-27hr after eclosion), and their incorporation into the pheromone was measured by the succeeding fractionation with normal-phase and reversed-phase TLC plates. [1-¹⁴C](Z)-11-Hexadecenoic acid changed more easily to bombykol than [1-¹⁴C]hexadecanoic acid, while [1-¹⁴C](E)-11-hexadecenoic acid and [1-¹⁴C]hexadecan-1-ol were scarcely incorporated into the pheromone. This result confirms the biosynthetic pathway via (Z)-11-hexadecenoate and (10E, 12Z)-10, 12-hexadecadienoate, which has been proposed by Yamaoka et al. and Bjostad and Roelofs. Some [1-¹⁴C](Z)-11-hexadecen-1-ol was changed to bombykol, suggesting that the alcohol was oxidized to (Z)-11-hexadecenoic acid and this acid was taken into the biosynthetic pathway.

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The pectate lyase I (PAL I) gene was cloned from Erwinia carotovora Er. The cloned DNA, 5.1 kb, seemed to contain the region necessary for the regulation of pectin lyase formation, as PAL I was induced by pectin in E. carotovora Er 18 containing the cloned PAL I gene. PAL I had a signal peptide of 22 amino acids which seemed to be cleaved between Gly and Ala. PAL I had a M.W. of 37, 587 composed of 345 amino acids. The presence of promoter and SD sequences was suggested upstream of the translational start cod on of the PAL I gene. A palindromic sequence, which might be important for the regulation of PAL I gene expression, was detected downstream from the putative promoter. Another open reading frame highly homologous to the PAL I gene was detected downstream from the PAL I gene and designated the PAL X gene. This gene had 81 % homology in 606 bp from the translational start codon with the PAL I gene.

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Transformation deficient mutants were isolated by nitrosoguanidine mutagenesis. A mutant Tra-12 was defective in the spontaneous development of competence for genetic transformation during culture growth, and showed no activator (competence inducing factor) activity inside or outside of the cells throughout growth. However, Tra-12 exhibited normal competence after the addition of an activator extracted from the wild type strain. This mutant needed a much larger quantity of the activator to develop a saturating level of competence and the induced competence disappeared more rapidly than in the wild type strain.

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A highly purified isomalto-dextranase (EC 3.2.1.94) was simply separated from the cell-free culture broth of Arthrobacter globiformis T6 by CM-cellulose column chromatography and characterized further. The purified enzyme was essentially homogeneous on PAGE and SDS-PAGE as well as isoelectric focusing. The enzyme was an acidic protein with pI 5.15. E^1%_1cm at 280 nm was 24.6. The molecular weight of the enzyme was estimated to be about 69, 000 by SDS-PAGE. No carbohydrate moiety seemed to be associated with the enzyme protein.
The optimum pH and temperature of the enzyme was pH 5.3 and 65°C, respectively. The enzyme was completely stable over the range of pH 3.0-8.0 at 4°C for 24 hr, and retained about 90% of its original activity after heating at 60°C for 10 min. Inactivation of the enzyme was found to be partial with 5mM Ag⁺, and complete with 5 HIM Hg²⁺, Fe³⁺, KMnO⁴, and NBS. The enzyme split dextran, retaining the α-configuration of the anomeric carbon atoms in the hydrolysis products. The K_m value of the enzyme for dextran was 0.038%. Isomaltitol was a potent competitive inhibitor (K_i=0.79 mM)

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The double bonds of 2-hydroxy-6-oxo-6-phenylhexa-2, 4-dienoic acid (HOPDA) were stabilized by methylation to establish which of the double bonds of the meta ring-fission compound of biphenyl was reduced by the HOPDA reducing enzyme. HOPDA reducing enzyme III converted 2-methoxy-6-oxo-6-phenylhexa-2, 4-dienoic acid methyl ester into 2-methoxy-6-oxo-6-phenylhexa-2-enoic acid methyl ester. To discover the metabolic pathway of HOPDA, partially purified enzyme fractions were used. The eluate from a 2nd column of DEAE-cellulose transformed HOPDA to γ-benzoylbutyric acid, 2, 6-dioxo-6-phenylhexanoic acid, and γ-benzoylbutyraldehyde. Fractions passed through the 1st column of DEAE-cellulose formed γ-benzoylbutyric acid and 2-hydroxy-6-oxo-6-phenylhexanoic acid from HOPDA. Based on these data and previous reports, a new metabolic divergence of biphenyl and related compounds was proposed.

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The effects of dietary fat types on the thermogenic activity of brown adipocytes isolated from rat were examined. When beef tallow (saturated fatty acids+ oleic) and safflower oil (linoleic) were the dietary fats, the respiration rates of brown adipocytes activated either by norepinephrine or an uncoupler of mitochondrial respiration (carbonylcyanide-m-chlorophenylhydrazone) were both slightly higher in rats fed the polyunsaturated fat. When the effects of safflower oil and evening primrose oil (linoleic +γ-linolenic) were compared, the activated respiration rate tended to be higher in the latter. The respiratory responses to varying concentrations of norepinephrine were apparently dependent on the dietary fat types. Triglyceride stored in interscapular brown adipose tissue appeared to be modified by dietary fat types. Dietary fat also characteristically modified the fatty acid compositions of interscapular brown and epididymal white adipose tissues. Thus, the type of dietary fat caused an alteration to the thermogenesis of brown adipose tissue at the cellular level.

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We isolated seven kinds of oligosaccharides from the hydrolysate of konjac (Amorphophallus konjac) glucomannan by a purified extracellular β-mannanase from Penicillium purpurogenum No. 618. These oligosaccharides were identified as M-M, G-M, G-M-M, M-G-M, G-G-M, M-G-M-M, and M-G-G-M; where G- and M- represent β, 4-D-glucopyranosidic and β, 4-D-mannopyranosidic linkages, respectively. The mode of action of the mannanase on the glucomannan is discussed on the basis of the structure of the above oligosaccharides.

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The aroL gene, encoding shikimate kinase of Brevibacterium lactofermentum, a coryneform glutamic acid-producing bacterium, was cloned. Recombinant plasmids containing the aroL gene caused elevated levels of shikimate kinase synthesis in B. lactofermentum. It was found that in addition to the aroL gene, the aroB and aroE genes, encoding dehydroquinate synthase and shikimate dehydrogenase, respectively, also existed on these recombinant plasmids, in complementation tests with various Escherichia coli and B. lactofermentum aromatic amino acid auxotrophs. The aroL, aroB and aroE genes of B. lactofermentum are located closely on the cloned DNA fragment, in that order. It was shown that at least these three aro genes form a cluster on the chromosome of B. lactofermentum.

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An acidic arabinoxylan occurring in the hemicellulose I fraction (4% potassium hydroxide extract) of cell walls of immature barley plants was isolated and characterized by methylation and fragmentation analyses. The results indicated that the acidic arabinoxylan had a linear backbone chain of β-l, 4-D-xylose residues, about 50% of which were substituted at the 2 and/or 3 position, mainly with arabinofuranose and glucuronic acid residues.

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The antioxidant effects of various food proteins such as gluten, casein, gelatin, gliadin and egg white were examined in powder model systems of these proteins simply mixed with safflower oil or sardine oil under a-moderate environment (37ºC, RH = 30-50%). Both the peroxide and TBA values in the mixture of gliadin and safflower oil or sardine oil were maintained at marginal levels throughout the experimental period. After indicated periods, the amounts of oil (triglyceride) and its constituent TUFA' were measured by thin-layer and gas chromatographic means, respectively. As a result, the two kinds of oils were found left almost intact in their corresponding mixtures. Although egg white was somewhat inferior to gliadin in the preservability of safflower oil at stages exceeding a period of 4 weeks, similar effectiveness was observed for the mixtures of this protein and oils.- The other proteins were not so effective as gliadin or egg white in protecting these edible oils against oxidative damage. It thus may safely be said that the high antioxidant effect of gliadin or egg white can be elicited not only upon free PUFA but also upon edible oils rich in PUFA.

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A cleavable photoactivable heterobifunctional reagent, the N-hydroxysuccinimide ester of 1-azido-5-naphthalene sulfonyl S-carboxymethylthiocysteamine (NHS-ANS-CTC), was synthesized and characterized. The reagent was applicable to the group-directed modification of protein ligands, such as an invertebrate lectin and a trypsin inhibitor. The modified ligands bound to rabbit erythrocyte ghosts and trypsin, respectively. Upon exposure to ultraviolet light, the modified ligands reacted with their binding proteins to form cross-linked fluorescent products. The crosslinked fluorescent complexes were readily cleaved by reducing the disulfide bond of the reagent, leaving the fluorescent probe on the binding proteins. The photolabeled binding proteins were analyzed by SDS-polyacrylamide gel electrophoresis. The fluorescence intensity of the fluorescent probe was enhanced by 4 - 8 times to improve sensitivity when the SDS-gel was dehydrated with methanol. This phenomenon was also observed with the proteins labeled with l-dimethylamino-5-naphthalene sulfonyl chloride.

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SAP, originally found as an aggregation factor of S. marcescens, was composed of about 75% protein and 25% sugar which consists of glucose, glucosamine, and galactosamine. SAP was stable against enzymatic digestion (37°C, 1 hr) by some proteinases and polysaccharide-hydrolyzing enzymes. The aggregation activity of the factor toward S. marcescens cells was inhibited by bovine serum albumin, ATP, and EDTA, and SAP activity was not restored by the addition of a sufficient amount of calcium ions except for the inhibition by EDTA. It was thought that these inhibitors have an effect on SAP itself or on the binding of SAP to the cells. The aggregation of S. marcescens cells by SAP was temperature- and calcium ion-dependent, and consists of two steps, which are the binding of SAP to the cells and subsequent cell aggregation. The first step proceeded at 37°C in the absence of calcium ions, but the second step required calcium ions.

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Ninety-two thiolcarbamates with various substituents at the nitrogen and sulfur atoms, and their related compounds were synthesized, and their fungicidal activity against rice blast, Piricularia oryzae, and herbicidal activity against barnyardgrass, Echinochloa crus-galli, were determined in laboratory tests. The thiolcarbamate structure was necessary for the high fungicidal and herbicidal activities. The hydrophobicity of the substituents at the nitrogen atom was shown by the adaptive least-squares (ALS) method to be favorable to the fungicidal activity. The bulkier the substituents at the nitrogen atom, the less was the fungicidal activity. However, bulkiness of the substituents at the nitrogen and sulfur atoms was unfavorable to the herbicidal activity. The existence of a hydrogen atom at the nitrogen atom was favorable to fungicidal activity, but not to herbicidal activity. Correlation analyses were made to find compounds with both fungicidal and herbicidal activities against rice pests.

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The states of tryptophan residues in Abrus precatorius agglutinin (APA) were analyzed by chemical modification and solvent perturbation UV-difference spectroscopy. The number of tryptophan residues available for N-bromosuccinimide (NBS) oxidation increased with lowering pH, and 20 out of the 24 tryptophans in APA were modified at pH 3.0, while 2 tryptophans were eventually oxidized at pH 5.0. Modification of tryptophan greatly decreased the binding of APA with saccharides, and only 4% of the hemagglutinating activity was retained after modification of 4 tryptophan residues/molecule. When the modification was done in the presence of lactose or galactose, 2 tryptophan residues/molecule remained unmodified with a retention of a fairly high hemagglutinating activity. The data from solvent perturbation UY-difference spectroscopy indicated that 6 tryptophans were on the surface of the APA molecule, and 4 tryptophan residues/molecule were shielded from the perturbing effect of the solvent upon binding with lactose.
Based on these results, we proposed that in the saccharide-binding site on each B-chain of APA there exists one tryptophan residue directly involved in saccharide binding, and near the binding site there is another tryptophan residue whose state is also changeable upon binding with saccharide.

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