Conformational changes of α_s-casein by heating were investigated by measuring ultraviolet difference spectra. The ultraviolet difference spectra at elevated temperature against 5.5°C were measured in various ionic strengths and pHs. Thermal effects of the difference spectra were cancelled by comparing with the spectra of model compounds such as lysozyme and ribonuclease, and the blue shift of α_s-casein spectra was observed at above 30°C in these all experimental conditions. This shift was considered to mean unfolding of the α_s-casein molecule. The aggregation of α_s-casein was observed above ionic strength of 0.4 by heating. These heat-induced changes were reversible until the aggregation was observed.

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After Screening 100 micro-organisms to detect intracellular myrosinase, only Aspergillus niger produced myrosinase.
Enzyme production was induced by the addition of ten percent of a mustard extract^* to the culture medium. The enzyme was produced in considerable amounts on the first and second day of cultivation. L-Ascorbic acid was an excellent carbon source.
The enzyme was unstable but was stabilized by coexistence with 2-mercaptoethanol (10^-2M ) and ascorbic acid (10^-3M).

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Mild acid hydrolysis of an acidic polysaccharide (APS-I) from soy sauce resulted in a degraded polysaccharide (DPS), the mixture of neutral sugar, D-galacturonic acid, its α-1, 4-linked homologous di- and trisaccharides, and acidic oligosaccharides containing residues of D-galacturonic acid and L-rhamnose. Besides the above-mentioned sugars, an aldobiouronic acid containing D-xylose moiety was also yielded in the enzymatic hydrolysates with a crude polysaccharidase preparation. However, only a β-1, 4-galactobiose was isolated from the lower molecular fraction of enzymatic digest of APS-I with a typical hemicellulase preparation. DPS containing 83% of D-galacturonic acid was able to be degraded by endo-polygalacturonase, but APS-I was not because of its highly branched structure. Partial structure of APS-I was discussed on the basis of these results. This consideration was also supported by the periodate oxidation study.

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Separation of asymmetric amines by derivatization to the corresponding amides with N-trifluoroacetyl-L-prolyl chloride was carried out by gas-liquid chromatography, and the structure-separation relationship was studied. For a series of ring-substituted 1-phenyl or naphthylalkylamines, diastereoisomeric amides were better resolved on a relatively polar column than on a nonpolar column with the L(+) forms eluted before the L(-) forms and the separation was poorer as the alkyl group attached to the asymmetric carbon atom was varied from isopropyl to methyl to n-propyl to isobutyl. On the contrary, for another series of ring-substituted 1, 2-diphenylethylamines, the isomeric amides were better resolved on a nonpolar column than on a polar column, the L(+) forms being eluted with longer retention than the L(-) forms, and the separation was better when the alkyl group substituted for a hydrogen of the phenyl group at α-position was bulkier. Furthermore, the optical purity of asymmetric amines was determined by measuring gas chromatographic peak areas of diastereoisometic amide components.

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Effects of irradiated sugar solutions on the growth and viability of E. coli B were investigated on glucose, fructose and sucrose. The antibacterial effect was demonstrated to be classified into two types; the bactericidal effect was developed in every sugar solutions irradiated in air, while the bacteriostatic effect was found especially in fructose irradiated in air free. The bactericidal activity was abolished by heating, pH change to alkali, and addition of catalase or ferrous ions, suggesting its entity is a peroxide products(s). No appreciable activity was observed with the radiation produced hydrogen peroxide and low molecular carbonyl compounds with each alone and even with their combination. Behaviours of the bacteriostatic activity on similar treatments indicate that the entity is unlikely a peroxide compound but a more thermostable and thiol reactive product.

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Out of some 750 strains of microorganisms, a potent bacterium for lipase production was isolated from soil and was identified as Chromobacterium viscosum.
The bacterium accumulates lipase in culture fluid when grown aerobically at 26°C for 3 days in a medium composed of soluble starch, soy bean meal, lard and inorganic salts.
Chrornobacterium lipase had an optimum pH of 7.0 for activity at 37°C, and an optimal temperature of 65°C at pH 7.0. The enzyme retained 80% of the activity when heated for 10min at 70°C. This lipase was capable of hydrolyzing a variety of natural fats and oils, and it was more active on lard and butter than on olive oil. The activity was stimulated by Ca²⁺, Mg²⁺, Mn²⁺ and inhibited by Cu²⁺ Hg²⁺ and Sn²⁺ It was not diminished but rather stimulated by a high concentration of bile-salts.

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An β-D-(1→3)-glucanase has been purified from the culture medium of Rhizopus niveus. The purification involves calcium acetate treatment, polyethylene glycol 6000 fractionation, CM-cellulose batch treatment, DEAE-cellulose column chromatography and gel filtration on Sephadex G-150.
The final preparation is homogenous on the basis of discelectrophoresis on acryl amide gel, sedimentation in the ultracentrifuge.
Some properties of the purified enzyme have been also tested.

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In this paper a new method of chemical determination of mevalonic acid in fermented materials is described. Mevalonic acid is identified as hydroxamate of its lactone using thin-layer chromatography, and is determined quantitatively as lactone-form by gas liquid chromatography. Mevalonic acid separated from kôji extract was identified by analysis of infrared spectrum. Saké and Kôji contained 4.6μg/ml and 43.3μg/g of this acid, respectively.

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As a simplified model of natural pyrethrins, trans-2, 5-hexadien-l-yl chrysanthemate (V), and its 2- or 3-methyl substituted homologues (III and IV), were prepared and tested for insecticidal activities against houseflies. All these compounds retained sufficient insect toxicity to illustrate an interesting relationships between chemical structure and insecticidal activity.
The cis isomer (XII) of compound V and two positional isomers, 2-methylene-4-penten-1-yl and 1, 5-hexadien-3-yl chrysanthemates (XIII and XIV), were also synthesized. Of these isomers, XIII was very slightly active, but the other isomers (XII and XIV) were completely ineffective.
On the other hand, the insecticidal activity of 5-hexen-2-yn-1-yl ester (XV), en-yne analogue of V, was almost the same as that of V.

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Studies were conducted on the degradation of N-lauroyl-L-valine by type cultured bacteria. Many strains could utilize sodium N-lauroyl-L-valinate as carbon and nitrogen sources for their growth. Metabolism of N-lauroyl-L-valine was investigated in detail using Ps. aeruginosa AJ2116. Lauric acid was identified by gas chromatography suggesting cleavage of N-acyl linkage in N-lauroyl-L-valine.
Lauric acid might be metabolized to capric acid (C₁₀) and caprylic acid (C₈) becuase the accumulated substances gave nearly identical peaks with those of authentic fatty acids on gas chromatograms. The experiment using N-lauroyl-L-valine (¹⁴C) indicated that ¹⁴CO₂ was produced as a final product. Valine was not detected because it might be metabolized very rapidly immediately after its release.
It was supposed that the enzymes or enzyme systems degrading N-lauroyl-L-valine might be constitutive from the experiment using two kinds of cells grown in the medium containing N-lauroyl-L-valine or nutrient broth.

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CD and ORD of twelve gibbane-10-carboxylic acid compounds with an aromatic A ring together with two related compounds were measured. The sign of the Cotton effect was found to be positive (negative) when the configuration of the C-10 carboxyl is β (α). The ORD also provided information to determine the configuration at C-4b. The C-10 carboxyl gave a stronger magnitude and redshift of the peak in a cis relation with 4b-H compared with that in a trans relation.

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The accumulation of NAD was studied by culturing yeast in the presence of NAD precursors. Among the strains tested, Saccharomyces carlsbergensis showed the highest ability for the accumulation of NAD. Additions of pantothenate, inositol, zinc ion and fatty acids were effective for the accumulation of NAD. Under the optimal culture condition, NAD level in Saceharomyces carlsbergensis reached 42mg per gram dry cells. Surfactants belonging to alkyl sulfate were effective on the leaking of the intracellular NAD, and about 75mg of NAD per 100ml was accumulated.

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A study was made to determine a method for the production of NAD using baker's yeast, and a suitable secondary culture condition for the accumulation of NAD was established. From the study the following results were obtained: Nicotinamide, nicotinic acid and adenine were effective on the accumulation of NAD. However, ribose or tryptophan-one of the precursor of NAD-was not effective. NaF, KCN or NaN₃-metabolic inhibitors-inhibited the accumulation of NAD. Baker's yeast obtained from commercial source was cultured secondarily in the medium containing 0.3% adenine, 0.6% nicotinamide in 0.2M K₂HPO₄ (50% fresh yeast was added), pH 4.5. Under this optimal condition, NAD content reached about 12mg/g dry cells (corresponding to 2.0mg/ml medium), and it corresponded to about 20 times that of the initial content.

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In the 1st experiment, the utilization of diammonium citrate (DAC) as a non-essential nitrogen source was studied in comparison with glutamic acid. Adult rats fed the amino acid diet containing DAC in place of glutamic acid as a nonessential amino acid maintained their body weights and had nitrogen balances almost equal to those of rats on the glutamic acid containing diets.
In the 2nd experiment, DAC-¹⁵N was orally administered after the rats were fed the DAC diet for a month, and the distribution of ¹⁵N in the rats' bodies and excreta was examined at the 6th, 12th, 24th and 48th hr after administration.
At the 6th hr, 85% of ¹⁵N intake was retained and 60% of ¹⁵N intake was found as protein-¹⁵N. At the 48th hr, retained ¹⁵N was 83% and protein-¹⁵N increased 5% above that at the 6th hr. The ¹⁵N concentration of non-protein fractions was higher and changed more rapidly than that of protein fractions, especially in the blood, liver and small intestine.
These results seem to indicate that DAC was utilized by rats fed a diet, in which nonessential amino acids were completely replaced by DAC. Gastrointestinal microbes might hardly play any role in the utilization of dietary non-protein nitrogen under these experimental conditions.

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S-SI, an microbial alkaline protease inhibitor, was produced in the culture broth of Streptomyces albogriseolus S-3253. S-SI was isolated from culture filtrate by salting out with ammonium sulfate, column chromatographies on DEAE-cellulose and Sephadex G-100. S-SI was also isolated by pH adjustment of the effluent from DEAE-cellulose column.
Crystallization of S-SI was carried out, and two distinct shaped crystals, needle shaped and rhombic crystal, were obtained. Homogeneity of these crystals were identified by polyacrylamide disc electrophoresis at various pHs.
S-SI retained its perfect inhibitory activity after treatment at 37°C for 25 hr in the pH range from 3 to 10, and 100°C for 10min in the pH range from 4 to 6.
From the examination of molecular weight determination with Sephadex G-100, the molecular weight of S-SI was decided to be about 27, 000.
S-SI was found to be highly specific towards microbial alkaline proteases.

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The ester and lactone fraction possessing the most attractive aroma was separated from the aroma concentrate of Ceylon flavory tea by silica-gel column chromatography and analyzed by GC-MS.
Methyl 2-(cis-2'-pentenyl)-cyclopentanone-3-acetate (methyl jasmonate), 5-(cis-2-pentenyl)5-pentanolide (jasmine lactone), 2, 3-dimethyl-2-nonen-4-olide, 4-octanolide, 4-nonanolide and 5-decanolide were newly identified as the constituents of tes aroma. Former two compounds seemed to carry a major share of aroma character of Ceylon flavory tea.

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By the addition of actithiazic acid, or acidomycin (ACM), to culture media, the accumulation of desthiobiotin by various microorganisms was enhanced from two-fold to about seventyfold, while that of biotin was markedly reduced. Especially, Bacillus sphaericus accumulated 350μg per ml of biotin-vitamers assayed with Saccharomyces cerevisiae. ACM was not incorporated into the desthiobiotin molecule by resting cells of B. sphaericus. The amount of biotin-vitamers assayed with S. cerevisiae which was synthesized from pimelic acid by the resting cells grown with ACM was twice as great as that synthesized by the cells grown without ACM. From these results, the mechanism of the controlling action of ACM on biotin biosynthesis was discussed.

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Biotin-vitamers were synthesized from glutaric acid by resting cells of certain strains of Agrobacterium. Pimelic acid, which has been known as a biotin precursor in many microorganisms, was not effective at all to this species. Optimum conditions for the biosynthesis of the vitamers by resting cells of Agrobacterium radiobacter IAM 1526 were investigated. L-Lysine was also effective, but the rate of the biosynthesis of biotin-vitamers from L-lysine was one-half that from glutaric acid. The vitamer synthesized was bioautographically identified as desthiobiotin. It was confirmed that ¹⁴C-labelled glutaric acid was incorporated into the desthiobiotin molecule.

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Detailed enzymatic properties of the ureido ring synthetase purified from Pseudomonas graveolens were investigated. Nucleotide specificity studies indicated that CTP, UTP, GTP, and ITP were each tenth to one-fifth as active as ATP. The effect of substrate concentration was examined. The Km values for 7, 8-diaminopelargonic acid, biotin diaminocarboxylic acid, NaHCO₃, ATP, and MgCl₂ were 1×10^-4M, 4×10^-5M, 1×10^-2M, 5×10^-5M, and 3×10^-3M, respectively. It was elucidated that only ADP was produced from ATP in both the reaction of desthiobiotin synthesis from 7, 8-diaminopelargonic acid and biotin synthesis from biotin diaminocarboxylic acid. The reaction was remarkably inhibited by Ni²⁺, Cd²⁺, Cu²⁺, Ag⁺, and As³⁺, while Mn²⁺ remarkably enhanced the enzyme reaction. The reaction was remarkably inhibited by metal-chelating reagents. It was elucidated that ADP had a competitively inhibiting effect on this enzyme reaction. 7, 8-Diaminopelargonic acid, which is the substrate for the desthiobiotin synthesis, competitively inhibited the biotin synthesis from biotin diaminocarboxylic acid. The stoichiometry of the desthiobiotin synthesis indicated that the formation ratio of desthiobiotin to ADP was 1 to 1.

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Four novel gibberellins GA₃₀, GA₃₁, GA₃₃, GA₃₄, five known gibberellins GA₈, GA₁₇ (free acid and its monomethyl ester), GA₁₉, GA₂₇, GA₂₇ and the gibberellin-like substances were isolated from immature seeds of evening-glory (Calonyction aculeaturn). The structures of GA₃₀, GA₃₁, GA₃₃ and GA₃₄ were elucidated as IX, XVIII, XXII and XXXIV, respectively. The three gibberellin-like substances were partially characterized.

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The Wittig reaction of (-)-α-ionone (VIa) with carbethoxymethylenetriphenylphosphorane afforded (-)-ethyl α-ionylideneacetate (VIIa). tert-Butyl chromate oxidation of the above ester (VIla) gave (-)-ethyl 4'-keto-α-ionylideneacetate (VIIIa). Selenium dioxide oxidation of (-)-α-ionone (IVa) in ethanol afforded (-)-1'-hydroxy-α-ionone (X), which reacted with carbethoxymethylenetriphenylphosphorane to give (-)-ethyl 1'-hydroxy-α-ionylideneacetate (XI). tert-Butyl chromate oxidation of the hydroxy-ester (XI) gave (-)-ethyl abscisate (XII) and ethyl 3'-keto-β-ionylideneacetate (XIII). The sensitized photooxidation of ethyl dehydro-β-ionylideneacetate (XVI) using chlorophyll was attempted.

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A neutral protease, which was prepared from Bacillus polymixa, was used on the digestion of myosin. Myosin was split to HMM and LMM. The HMM fraction was further digested with the protease and a subfragment-1 was prepared.
The sedimentation coefficient, s⁰_{20, w}, and the intrinsic viscosity of this subfragment-1 were determined as 5.6S and 0.08dl/g, respectively. The molecular weight was estimated to be about 120, 000 by the sedimentation equilibrium method. This subfragment showed the characteristic myosin-type ATPase; the ATPase was activated by Ca²⁺ ion or EDTA and inhibited by Mg²⁺ ion, the maximum activation of ATPase was obtained when 3.5 SH groups per 10⁵g of subfragment were titrated with PCMB.
The subfragment-1 possessed the ability to interact with F-actin and to accelerate G-actin polymerization.

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The syntheses of three dl-demethylvariotins are described.

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A newer method of the N-acylation of lactams via N-trimethylsilyl lactams is described.

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The mechanism of inactivation of a double-stranded DNA phage, phage J1 of Lactobacillus casei, by ascorbic acid was investigated.
Bubbling air, oxidizing agents and transition metal ions enhanced the rate of inactivation of the phage by ascorbic acid. In contrast, bubbling nitrogen gas, other reducing agents and radical scavengers prevented the inactivation. The results indicated that the inactivating effect of ascorbic acid was oxygen dependent and caused by free radicals formed during the autoxidation of ascorbic acid.
The target of ascorbic acid in the phage particle was not the tail protein but DNA. Ascorbic acid caused single-strand scissions in phage DNA, as exhibited by alkaline sucrose density gradient centrifugation analysis, and caused a slight decrease in the viscosity of DNA.

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A cellulase preparation which exhibits the highest activity at a lower pH range, 2.3 to 2.5, was purified from a commercial cellulase preparation from a culture filtrate of Asp. niger and referred to as acid-cellulase.
The purification involves ammonium sulfate fractionation, gel filtration and ion-exchange and adsorption chromatographies. The purified enzyme was revealed to be homogenous in ultracentrifugation and disc as well as ampholine electrophoreses and to be an acidic protein of which isoelectric point lied at pH 3.3. The sedimentation coefficient and molecular weight were determined to be 3.27S and 46, 000, respectively. The optical properties were also studied.

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Transaminations between L-amino acids and pyruvate or α-ketoglutarate(α-KGA) were observed in a cell-free extract of Acetobacter suboxydans (Gluconobacter suboxydans IFO 3172). The level of the activities of transaminations with pyruvate was greatly influenced by the kinds and amounts of nitrogen sources for growth media. The enzymic activities of transaminations with pyruvate in glutamate-grown cells were extremely higher than in yeast extract-grown cells. Nutritional components decreasing the activities were presumed to be some of amino acids and ammonium ion present in yeast extract. The activities of transaminations with α-KGA were not so variable in the presence or absence of the components.
The optimum pH of transaminations with pyruvate was in the range of 5.0_??_5.5 and that of the reaction with α-KGA in 8.0_??_8.5. The optimum temperature of the former was 65°C and that of the latter about 45°C. Some other different properties were also recognized between the two kinds of reactions.

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Some properties of a purified acid-cellulase produced by Aspergillus niger were investigated. The acid-cellulase was stable at the pH range between 4.0 and 10.0 and exhibited the highest activity toward glycol cellulose at pH 2.5. The optimum temperature of activity was measured to be 50°C, while the enzyme was inactivated above 40°C by heating for 1 hr. Insoluble cellulose such as filter paper was difficult to be attacked by the enzyme.
Mg²⁺ and Mn²⁺ ions inhibited the activity, while Co²⁺ ion caused a slight activation.
The nitrogen content of the enzyme protein was determined to be 14.37%. The enzyme contained 378 residues of amino acids rich in acidic amino acids, 12 residues of glucosamine and 10 residues of arabinose per molecule. N-terminus was not detected by DNP-method.

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The specificity of a rennin-like enzyme from Mucor pusillus Lindt was determined using synthetic peptides and oxidized insulin B chain as substrates. The results indicate that the enzyme exhibits specificity against aromatic, bulky or hydrophobic amino acid residues at both sides of the splitting point. The susceptibility of peptide substrates increases with the increase of their molecular size, indicating the significance of secondary interaction for hydrolysis. Z-tetrapeptides such as Z-Phe-_??_Leu-_??_(Ala)₂, Z-Gly-Phe-_??_Leu-Ala (the arrows show the bond split) are found as efficient substrates for the enzyme. The main points of cleavage in oxidized insulin B chain are; Phe-Val (1-2), Ala-Leu (14-15), Leu-Tyr (15-16), Tyr-Leu (16-17), and Phe-Phe (24-25).
The specificity of the M. pusillus enzyme is almost identical with that of the rennin-like enzyme from Mucor miehei, and similar to those of usual acid proteinases possessing trypsinogen activating ability, except that the latter enzymes show specificity against basic amino acid residues at the carbonyl-side of the splitting point.

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A biologically active metabolite designated Cyl-2 from a phytopathogenic fungus, Cylindrocladium scoparium, was found to be composed of four amino acid residues, which fully account for all of the atoms constituting Cyl-2. These amino acids were identified as L-pipecolic acid, L-isoleucine, D-O-methyltyrosine and 2-amino-8-oxo-9, 10-epoxydecanoic acid. Thus, Cyl-2 was established as a cyclotetrapeptide containing novel amino acid residues.

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