Some chemical and physical properties of agarose (AG) and agaropectin (AP) isolated from agar of various red seaweeds were studied. The two components were isolated by acrinol. Methanol containing sodium iodide was superior to the mixed solvent of ethanol and acetone (1:1) as solvent for removing acrinol. Greater value of the ratio of intrinsic viscosity of both AG and AP in the solution of 0.1M sodium chloride against that in the mixed solution of 4M urea and 0.001M sodium thiocyanate made water holding capacity greater except sample whose molecular weight is very small. Water holding capacity of AG was decreased with increasing ratio of D-galactose plus 6-O-methyl-D-galactose against 3, 6-anhydro-L-galactose, and with lower liquefying temperature of gel. In the case of AP, however, these relations were not always distinct.

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During the investigations on riboflavin glycoside formation by Aspergillus, Mucor, Penicillium and Rhizopus, a remarkable production of 5'-D-riboflavin-α-D-glucopyranoside was observed in several strains belonging to the genus Mucor when grown on a medium con-taining maltose and riboflavin. Several conditions on 5'-D-riboflavin-α-D-glucopyranoside formation were also investigated with washed mycellium of M. javanicus. Maltosyl com-pounds such as maltose, dextrin, amylose and soluble starch were the effective glucosyl donor, whereas glucose, fructose, sucrose, lactose and dextran were inactive.

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Some physical and chemical properties of urate oxidase (EC 1. 7. 3. 3) isolated from the cells of Candida utilis were investigated. The molecular weight was estimated to be 1.2×10⁵ by the equilibrium sedimentation and gel filtration methods. The isoelectric point was determined as 5.4 by the method of density electrofocusing. The enzyme showed a slight absorption at 410mμ, and the absorbancy at this wave length was only 3% of that at 280mμ. Contrary to urate oxidase from swine liver, the enzyme from yeast contained a negligible amount of copper, but it contained iron of nearly one atom per mole of the enzyme protein. The yeast urate oxidase was not inactivated by some chelators. However, it was easily inactivated with certain heavy metal ions such as Hg²⁺, and the inactivated enzyme was reactivated by the addition of thiols, indicating that the enzyme is a sulfhydryl enzyme. The inactivation of the enzyme with urea, on the other hand, was greatly accelerated by the addition of thiols, and some discussion was added to the results obtained.

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Various levels of dilauryl succinate with or without additional d-α-tocopheryl acetate and of diethyl succinate were fed to chicks for 4 weeks to examine the interrelationship between the esters and nutritional encephalomalacia.
Chicks fed dilauryl succinate at the level higher than 3% died with lesions in the cerebellum. The lesions were prevented by the supplementation of 25mg or more of d-α-tocopheryl acetate per kg of diet. Median lethal dietary level for males of meat-type and egg-type chicks at 3 weeks of age was 6.3 and 6.0%, respectively. That for females of meat-type at 3 weeks of age was 9.0%, suggesting that males were more sensitive than females. Diethyl succinate did not induce encephalomalacia.

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Mutant strains of Aspergillus sojae exhibited coordinate increases of acid proteinase, α-amylase, and cellulase and_??_decrease of pectin trans-eliminase accompanied with the hyperproduction of alkaline proteinase in wheat bran koji culture. The production of these enzymes in the wheat bran solid medium, liquid wheat bran-defatted soybean medium, and liquid glucose-peptone medium were surveyed. The analyses on the production patterns of these enzymes under the different cultural conditions suggest that mutation in these mutants producing elevated levels of the above enzymes is due to a more complex alteration.

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Physico-chemical properties of alkaline proteinase from the parent strain were compared with those from hyperproductive mutants of Aspergillus sojae. All the results on behavior of enzyme protein to ion exchange resin and celluloses, gel filtration, ultracentrifugal sedi-mentation, disc electrophoresis and isoelectrofocusing on polyacrylamide gel column, specific activity, substrate specificity, and kinetic constants provided evidence in favor of the con-clusion that the parent and mutant strains produced the chemically identical enzymes and that superactivity of alkaline proteinase in culture extracts or filtrates of mutant strains was not attributed to alteration of catalytic property of the enzyme, but to hyperproduction of the identical enzyme resulting from the genetic change in the regulatory mechanism of enzyme synthesis.

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Oxidized spermine and oxidized spermidine inhibited markedly the infectivity of the 6M-urea treated φX174 particle, whereas they did not inactivate the infectivity of the untreated phage particle. They also markedly inhibited the infectivity of φX174 DNA, while φX174 RF I DNA was less sensitive to these reagents. These facts suggested that oxidized polyamines could react with phage DNA.
The possible reasons of the insensitivity of phage φX174 particle and less sensitivity of φX174 RF I DNA to these reagents were discussed.

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In streptomycin-producing Streptomyces griseus HUT 6037, an enzyme which phosphorylated streptomycin appeared in old mycelium at stationary to autolyzing stage. This enzyme phosphorylated streptomycin with equimolar ATP at C₆-OH in the streptidine moiety. This phosphomonoester of streptomycin was identified with the phosphorylated streptomycin (referred to as L compound) which was previously reported to accumulate in the culture broth when the pH was controlled below neutral.

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Streptomycin-phosphorylating enzyme was reported previously to be produced in my-celium of Streptomyces griseus HUT 6037 at late stage of growth. In the present investi-gation, this enzyme was purified 200 times as high in specific activity as cell-free extract by means of salting out, chromatography on DEAE-Sephadex A-25 and gel filtration with Sephadex G-100. This enzyme was most stable at pH 8.0 and required 10^-2_M Mg²⁺ in the reaction mixture for the highest activity. It lost the activity by heat treatment at 40°C for 15 min in absence of the substrate.
Mutant cultures were prepared on productivity of or tolerance to streptomycin, and their capacity to produce streptomycin-phosphorylating enzyme was examined. The cul-tures which had low to no capacity to produce streptomycin produced a small amount to none of the enzyme, suggesting that production of the streptomycin-phosphorylating enzyme had some correlation with streptomycin productivity of the culture. But no definite cor-relation was observed between productivity of the enzyme and the capacity to tolerate streptomycin.

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The origin of each carbon of anhydrosepedonin produced by Sepedonium chrysospermum has been elucidated by carbon-14 tracer method. At first, the degradation pathways adequate to such object was studied. The radioactivity incorporated in sepedonin and anhydrosepedonin was considerably high when acetate-1-¹⁴C, acetate-2-¹⁴C and formate-¹⁴C were used as the precursor. The feature of the labeling pattern of anhydrosepedonin was analogous to those of the other fungal tropolones. The carbon atom derived from formate was almost exclusively situated at C-7 position of the tropolone ring. As a whole, the labeling pattern demonstrated that anhydrosepedonin might be synthesized through the poly-ketomethylene pathway.

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The production of biotin and bisnorbiotin from biotin diaminocarboxylic acid by the resting cell system of microorganisms was studied. It was found that the resting cells of Bacillus sphaericus convert biotin diaminocarboxylic acid into biotin, and the cells of Rhodotorula rubra potently convert it into bisnorbiotin through biotin. The conversion products from biotin diaminocarboxylic acid by these resting cell systems were chromatographically identified as biotin and bisnorbiotin. These conversions were markedly stimulated by addition of certain amino acids, especially alanine and glutamic acid, suggesting the important role of amino compound in the formation of ureido ring of biotin and bisnorbiotin molecules. This reaction occurred rather favorably under aerobic conditions.

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During the course of investigations on the metabolism of 7, 8-diaminopelargonic acid by microorganisms, it was found that a strain of Pseudomonas effectively converted 7, 8-diaminopelargonic acid into biotin vitamers. The vitamers formed were separated by the ion exchange column chromatography, into Fraction A and Fraction B. The vitamer I was isolated from the Fraction A in powder form. The isolated vitamer I did not support the growth of Saccharomyces cereaisiae, but did support that of Bacillus subtilis, and its Rf values in several system were identical with those of authentic bisnordesthiobiotin. The vitamer II which was shown to support the growth of Saccharomyces cerevisiae and Bacillus subtilis, was isolated from the Fraction B in crystalline form. The crystals were identified as desthiobiotin by physico-chemical and biological examinations. Then, the metabolic route of 7, 8-diaminopelargonic acid which included the carboxylation and β-oxidation are proposed in this paper.

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It has been demonstrated regarding the formation of ketosphingosine base that the en-zymatic condensation of palmitoyl-CoA with serine in the particulate preparation from rat liver produces only ketodihydrosphingosine in the absence of flavin nucleotide but produces ketosphingosine as well as ketodihydrosphingosine in the presence of flavin nucleotide. The findings suggest that ketodihydrosphingosine is formed first from the enzymatic reaction of palmitoyl-CoA with serine and then converted to ketosphingosine by dehydrogenation with the flavin enzyme.

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Relation between sulfhydryl groups in soybean proteins and the physical properties of tofu was studied. Changes in the amount of sulfhydryl groups by heating or treatment with urea were more rapid in 11S protein as compared with 7S protein. Moreover, by changing the amount of sulfhydryl groups in proteins by N-ethylmaleimide, 2-mercapto-ethanol and dithiothreitol, the physical properties of tofu from 11S protein were more significantly effected than that from 7S protein. Namely, tofu-gel from I1S. protein got harder and stronger as the amount of sulfhydryl groups increased.
The results may suggest that tofu prepared from 11S protein has more disulfide bonds in its gel than that from 7S protein.

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A thiamine-requiring strain of Corynebacterium was found to accumulate a ketopentose extracellularly from gluconate. The ketopentose was isolated from the culture medium and identified as Dribulose. The accumulation of D-ribulose was significantly influenced by the concentration of thiamine in the medium. The maximum yield of D-ribulose was obtained at a thiamine concentration of 10μg per liter, whereas good growth was favored at thiamine concentrations greater than 50μg per liter. The accumulation of Dribulose reached the concentration of 9.5mg per ml after cessation of cell growth in shake culture at 30°C in a medium containing 6% potassium gluconate as a carbon source.

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A gluconate-utilizing strain of Corynebacterium was found to be capable of utilizing aldopentoses and producing corresponding pentitols when pentoses were added to the medium containing gluconate as u carbon source during the cultivation of the organism.
Pentitols produced from D-xylose, L-arabinose, and D-ribose were isolated from the cultured medium and identified as xylitol, L-arabitol, and ribitol, respectively.
The pentitol production was significantly influenced by the concentration of gluconate in the initial medium and that of pentose added to the medium during the cultivation.
The amount of xylitol, L-arabitol, and ribitol reached 69mg/ml, 60mg/ml, and 32mg/ml, respectively, after 14 days of incubation when pentoses were added to the medium con-taining 9.6% potassium gluconate to give a final concentration of 150mg/ml.

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Two 3-(7'-theophyllyl)glycals, (IV) and (V), were synthesized by fusion of theophylline and the appropriate glycals in the presence of p-toluenesulfonic acid. The structure and stereochemistry of the glycals were determined mainly from NMR analysis of their dihydro and 1, 6-anhydro derivatives.

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Total syntheses of (±)-steviol (IIa) and (±)-kaur-16-en-19-oic acid (III) were accomplished. A synthesis of methyl (±)-8α-carboxymethylpodocarpan-13-on-19-Date (IVa), a degradation product of steviol, was also described.

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The metabolic activation mechanism of tri-p-ethylphenyl phosphate (TPEP, a neurotoxic substance) was elucidated. In vivo experiments of houseflies, mice and hens, six to seven metabolites of TPEP-³²P were detected. The main metabolite was isolated and characterized as di-p-ethylphenyl p-(α-hydroxyethyl)phenyl phosphate. Three others were also identified by cochromatography as di-α-hydroxy, tri-α-hydroxy and mono-α-oxo derivatives of TPEP. In vitro experiments indicated that the p-ethyl group of TPEP was hydroxylated by the action of a microsomal oxidase fortified with NADPH to give an α-hydroxyethyl group, which was then transformed to an acetyl group by the action of a soluble dehydrogenase. The oxo metabolites showed certain degree of antiesterase activity and neurotoxicity to damage the sciatic nerve and to cause ataxia in hens.

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Metabolism of organophosphorus fungicide Hinosan^® (O-ethyl S, S-diphenyl phosphorodithioate) by mycelia of P. oryzae, rice blast fungus, was studied using ³²P-, ³⁵S- and non-label-ed compounds, by ion exchange chromatography, paper chromatography, thin-layer chromatography and gas chromatography, and identifying the metabolites and their derivatives with authentic compounds.
The main metabolic pathway is hydrolysis of one P-S linkage followed by the other P-S linkage or ethyl ester linkage and finally yielding phosphoric acid. A part of the fungicide metabolizes to hydroxylated intermediate metabolite, O-ethyl S-p-hydroxyphenyl S-phenyl phosphorodithioate. No significant difference in rate and mode of metabolism was found in this experiment between susceptible and resistant clones against the fungicide.

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