A study was done to measure the saccharose flux permeating through the oil layer of the dispersed vesicular globules in a series of W/O/W-type multiple emulsions, considering in connection with the effect of entrapped invertase on the hydrolytic activity in the vesicular globules. The W/O/W emulsions containing a definite quantity of invertase in the inner aqueous phase of the globules were prepared using a mixture of Span 80 and SDS, and were dialyzed against an aqueous solution of 0.1 M saccharose for over 10 days at 25°C. Thus, it was possible to follow an increasing pattern of reducing sugar with each sample in the dialysis container according to the hydrolysis of saccharose, which was diffusing into the inner aqueous phase from the outer aqueous medium permeating through the oil layer. A range of values from 1.5 to 11.2 pM sec^-1 were observed for the molar flux of saccharose against 1 cm² of the oil layer. Although the values obtained were scattered within the above range due to the variations of the samples, the hydrolytic activity of invertase seemed to be kept in the vesicular globules during a span of the dialyzing procedure.

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Dialdehyde derivative of cyclodextrin (dial-CD) was prepared by oxidation with sodium metaperiodate, because the oxidative cleavage with periodate would theoretically provide 2', 3'-dialdehyde derivatives of the α-1, 4-linked glucans. The α-CD oxidized with equimolar periodate (dial-α-CD I) was separated from the unoxidized native α-CD by column chromatography on Sephadex G-15, where the peak of dial-α-CD I was eluted faster than the native α-CD and corresponded to the reducing power. Since the hydrated forms of dial-CD gave no characteristic spectral pattern of the dialdehyde groups, the structure of the dial-CD was deduced by IR and ¹³C-NMR spectral analysis for a dicarboxylate derivative of the dial-α-CD. The dial-α-CD I has an average of 3.5 glucose residues oxidized into the dialdehyde structure. Among the possible 13 isomers of the dial:α-CD, isomers IA, IIAB, IIAC, IIIABC, and IIIABD were the predominant forms, which were identified by the measurement of maltooligosaccharides derived from the dial-α-CD I by NaBH₄ reduction and acid treatment. Moreover, the reactivity of the dial-α-CD I was demonstrated by adduct formation with lysine and glycine, which was analyzed by gel filtration patterns on a Sephadex G-15 column.

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Dialdehyde derivatives of cyclodextrin (dial-CD) were prepared by the periodate oxidation method. The dial-CD inhibited not only exo-type amylases (β-amylase and glucoamylase) but also endo-type α-amylase, and the degree of inhibition was much stronger than that with the corresponding native cyclodextrin (CD). α-Glucan phosphorylases from muscle, yeast, and potato were also inhibited by the dial-CD and the resulting Ki values for the muscle enzyme were 7 - 8-fold lower than those of the native CD. A progressive inactivation of the muscle phosphorylase by the dial-α-CD suggested that this compound would be useful as an affinity-labeling reagent for phosphorylase. Although the dial-CD was less effective for the irreversible inactivation of amylases than the phosphorylase, the potent inhibition of several amylases by the dial-CD would provide an useful inhibitory compound for kinetic analysis.

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Rabbit muscle phosphorylase b was modified with a substrate analog, the 2', 3'-dialdehyde derivative of α-cyclodextrin (dial-α-CD). Although the inhibition of phosphorylase b by α-, β-, and γ-cyclodextrins gave rather high Ki values (10-25 ITIM), the dial-CD gave much smaller Ki values of 1.2-3.5mM. Moreover, the latter inhibition was time-dependent and accelerated by higher pHs and higher concentrations of dial-CD. Incorporation of the dial-CD into the enzyme was proportional to the loss of enzyme activity and became stationary at about 1 mol of dial-CD bound to a mol of enzyme subunit. Modification was greatly suppressed by the presence of substrate glycogen. Glucose 1-phosphate was not effective. The dial-CD-modified phosphorylase b was purified by Sephadex G-75 and Con A-Sepharose column chromatography. The modified enzyme gave a single band of activity having a K_app of 6.3% glycogen on affinity gel electrophoresis, which showed that the modified enzyme had a very low affinity for glycogen. Comparison of Km values of the native and modified phosphorylase b showed that the Km values for the glucan substrates increased 8 to 11-fold in the modified enzyme. These results suggested that the glycogen storage site of muscle phosphorylase b might be modified with dial-CD and the modified enzyme significantly decreased in the affinity for the substrate glycogen.

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Two kinds of dimeric procyanidins were isolated in pure form from azuki beans by preparative HPLC. They were identified as procyanidins B-1 and B-3, on the basis of their UV, IR FAB-MS and ¹H-NMR spectra, and an analysis of the acid hydrolyzed products. The procyanidins were evaluated as antioxidants for linoleic acid in an aqueous linoleic acid-β-carotene model system. In the range of the tested concentrations (5 × 10^-5 - 100 × 10^-5%) and pH values (7-9), they showed remarkable antioxidative activities. Their activities were much stronger than those of such commercially available natural antioxidants as ascorbic acid, γ-oryzanol, gallic acid, L-tryptophan, (+)-catechin and D-α-tocopherol. The hydrogen- or electron-donating activities of procyanidins to the DPPH radical in a 50% ethanol solution were also stronger than those of ascorbic acid and D-α-tocopherol.

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The effects of intraperitoneally injecting pargyline, which elevates the brain serotonin (5-HT) content, and p-chlorophenylalanine (p-Cl-Phe), which lowers the brain 5-HT content, on food selection in growing rats choosing freely between two diets containing various amounts of amino acid (Val, Thr or Trp) or protein (casein) were investigated. Under the conditions of this experiment, no consistent correlation was observed between the amount of amino acid or protein intake and the plasma ratio of Trp to large neutral amino acids (Trp/LNAA). Also, neither the amino acid nor protein intake under the conditions of the selection paradigm was affected, despite the brain neurotransmitter (5-HT) concentration being markedly altered. These results suggest that the concentration of 5-HT in the whole brain will not regulate the amino acid or protein intake and selection. The behavioral aspect of selection for dietary amino acid or protein appears to be related to the maintenance of amino acid concentrations in the blood and brain within normal limits, regardless of the brain 5-HT level.

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The changes in the volatile flavor compounds of powdered katsuobushi during storage were studied. The headspace vapor of powdered katsuobushi was adsorbed on activated charcoal and then analyzed by gas chromatography (GC) and combined gas chromatography and mass spectrometry (GC-MS). The aroma concentrate obtained on simultaneous distillation-extraction (SDE) was also analyzed.
Methanethiol, dimethyl sulfide/carbon disulfide and 2-butanone in the headspace vapor greatly decreased, and hexanal and 2, 3-pentanedione greatly increased on the first day. On the other hand, hexanal, (2E)-hexenal and 2, 3-pentanedione in the aroma concentrate greatly increased, the changes in phenols and ethers, in quantity, being relatively small.
On headspace vapor analysis, 24 compounds were identified, of which 11 were newly found as aroma substances in katsuobushi.

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The metabolic fate of vanillylamine, a component of capsaicin, in Pseudomonas fluorescens B56 was examined under both growing and non-growing conditions. Under growing conditions, the cells metabolized vanillylamine to vanillin, and vanillin to vanillic acid and a small amount of vanillyl alcohol. Under non-growing conditions, the cells produced vanillin, vanillic acid and protocatechuic acid from vanillylamine, and vanillic acid supplied to the medium was converted to protocatechuic acid. It is thus suggested that vanillylamine is metabolized to vanillic acid through vanillin by Pseudomonas fluorescens B56 in a rich medium, however, in a starving medium, the bacterial strain further metabolizes vanillic acid to protocatechuic acid. The vanillylamine metabolic activity was slowly induced by the substrate.

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The relationship between protein intake and the ratio of N¹-methyl-2-pyridone-5-carboxamide and N¹-methyl-4-pyridone-3-carboxamide to N¹-methylnicotinamide excretion in rats and humans was investigated. This ratio was recommended as an index of the niacin status by de Lange and Joubert. In rats, this ratio decreased on changing the diet from a normal niacin-containing diet to an excess niacin-containing diet. Furthermore, this ratio extremely increased on changing the diet from a 10% casein diet to a 20% casein diet, and decreased on changing the diet from the 20% casein diet to the 10% casein diet, even though the intake of niacin in both cases was about the same. In humans, the correlation between protein intake and this ratio is statistically significant at p<0.001 (r = 0.728), although the correlation between niacin equivalent intake and this ratio is not significant. Therefore, the ratio of N¹-methyl-2-pyridone-5-carboxamide and N¹-methyl-4-pyridone-3-carboxamide to N¹-methylnicotinamide excretion might be a more useful index for assessing the protein status than as an index for assessing the niacin status in rats and humans.

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The complete coding region of the gene (gshI) for γ-glutamylcysteine synthetase (GSH-I) of Escherichia coli B was fused with a promoter fragment of Saccharomyces cerevisiae, P8, which was newly cloned in this study. Since the P8 fragment functioned not only as a transcriptional promoter but also the code for the amino terminal residue, the fused gshI was translated into the fused GSH-I in S. cerevisiae. The GSH-I activity and glutathione (GSH) content of the transformant increased more than 1, 000-fold and about 3-fold, respectively. DNA sequencing of the fused gshI revealed that there were two TATA boxes at positions -25 and -165, two CAAT boxes at -248 and - 278, and two possible mRNA start sites at - 17 and - 7 from the putative initiation codon ATG. The fused gshI had an open reading frame of 1, 007 amino acids, in which the C-terminal 517 amino acids were from gshI. Though the calculated molecular weight was 112, 668, the purified fused GSH-I had a molecular weight of 55, 000 and was immunologically identical to the GSH-I of E. coli B. These results suggested that the fused GSH-I was posttranslationally processed to an active, small protein.

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Inclusion equilibria of cyclodextrins and aroma components in aqueous ethanol solution were studied to evaluate the retention of aroma in liquor with cyclodextrins.
The dissociation constants of inclusion complexes were measured by head space gas chromatography. The standard enthalpy and other thermodynamic parameters were calculated from the relation between the temperature and the dissociation constant. The retention abilities were evaluated quantitatively by the parameters obtained.
The vanishing of aroma by evaporation or adsorption and the effects of cyclodextrins on the retention of aroma in liquor were simulated mathematically using the dissociation constants obtained. The calculated values agreed well with the experimental values.

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The relationship between imbibitional damage and the initial water content of soybean seeds was investigated. Imbibitional damage such as the lack of cotyledons was serious at water contents below 10% but not over 20%. The water content of 10% was the point below which the signal of inorganic phosphate in cytoplasm disappeared in ³¹P-NMR spectra and the signals of sucrose in vacuoles disappeared below 20% in ¹³C-NMR. Based on these results, it was concluded that the primary course of imbibitional damage was the mechanical destruction of cotyledons by the swelling of stored materials associated with rapid sorption of water into dry seeds.

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The physical characteristics of water in soybean seeds were investigated in relation to the water content, respiratory activity, and the imbibitional damage during germination. Imbibitional damage was severe at water contents below 10% where only the strongly bound water existed while it did not appear over 20% where free water existed and the membranes of cells had already recovered their functions. Taking the changes of ¹H-NMR signals with water contents into account, the water absorbed in humid air was considered to be concentrated in a certain place in soybean seeds while the water absorbed by soaking was restricted by stored materials. The respiratory activity of seeds which absorbed water from humid air rose according to the increase of water content with a tendency similar to the free water.

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A nitrite-oxidizing enzyme was isolated (1300-fold purification, 15% yield) from Candida rugosa IFO 0591 using a reaction mixture containing glucose oxidase and glucose. The enzyme (molecular weight 220, 000) consisted of four identical subunits with molecular weight of 58, 000. It showed absorption maxima at 277 and 405 nm with small peaks at 492, 535, and 625 nm. The spectrum was not altered by the addition of dithionite. These and other properties suggested that the enzyme was catalase and that the nitrite-oxidizing reaction was dependent on its peroxidase activity. Some aspects of the nitrite oxidation by the purified enzyme and various preparations of C. rugosa are described.

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A killer yeast designated strain SW-55, isolated from the skin of grape berries, had killer activity of a novel type. Taxonomic studies revealed that the killer strain belonged to the genus Candida. The killer activity had a broad optimum pH range, high thermal and pH stabilities, and broad anti-yeast spectra. The SW-55 killer character may be encoded by chromosomal genes, not by extrachromosomal ones.

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The killer toxic substance of Candida SW-55 was separated into two components, I and II, by CM-Sepharose CL-6B column chromatography. They were purified 20 700-fold and 11 100-fold from the culture filtrate of SW-55, respectively. Each purified toxin gave a marked glycoprotein band with molecular mass of 36 kDa on SDS/polyacrylamide gel electrophoresis. Toxins I and II had almost the same isoelectric points, 3.4-3.7 and 3.3-3.8, respectively. Toxin I had strong killer activity against Saccharomyces cerevisiae, Candida glabrata, Hansenula anomala, and Rhodotorula rubra (MIC 0.2-0.3μg/ml), and moderate activity against Kluyveromyces lactis (MIC 2.5μg/ml) and Pichia membranaefaciens (MIC 0.6 μg/ml) but bacteria, fungi, and the other yeasts tested were not affected by toxin I even at the high concentration of 20 μg/ml. Toxin II turned out to be less active than toxin I and the MIC for S. cerevisiae Epernay was 0.4-0.5μg/ml.

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The title compound was obtained by McElroy et al. as a crude product without definite characterization due to its instability and the lack of a suitable analytical method other than bioluminescence. In this research, reliable methods for analyzing and isolating the unstable luciferyladenylates were established by means of HPLC. Firefly L-luciferin was condensed with adenylic acid, the chiral center of L-luciferin being epimerized when adenylated. After evaporating the solvent, the residue was washed with EtOAc and CH₂C1₂, and extracted with 6 M urea. The extract was chromatographed on a reversed-phase C₁₈-HPLC column. The D-luciferyl-D-adenylate contained less than 8% luciferin and its diastereomeric purity was more than 98%. The luciferyladenylates are extremely unstable; they are hydrolyzed to luciferin and adenylic acid, and epimerized quite easily in neutral to basic buffers. L-Luciferyl-D-adenylate emits light with firefly luciferase of about 1/3 the light yield compared to that of the D, D-isomer, possibly because of partial epimerization of the L, D-isomer to the D, D-isomer during the reaction.

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Feeding a cystine-excess diet caused growth retardation, hepatomegaly and hypercholesterolemia. Studies were undertaken to examine whether some dietary fibers and cholestyramine could prevent the hypercholesterolemia induced by feeding a cystine-excess diet for 6 days. Of the dietary additions tested, carrageenan, chitin, chitosan, cholestyramine, guar gum, konjac mannan, locust bean gum, tamarind gum, tra gum and xanthan gum were effective in preventing hypercholesterolemia.

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A simple method has been developed for analysis of gizzerosine in fish meals. A sample, hydrolyzed with 6N HCl, was transferred into an Amberlite IR CG-50 column which was equilibrated with sodium borate solution (0.045 M, pH 8.25). After elimination of a large portion of amino acids from the column, gizzerosine was eluted with 0.5N NH₄OH and then measured by HPLC. HPLC separation was done with an analytical column of Hitachi 2619-F and gradient elution with three solvents (two borate buffers-pH 9.2 and 10.7, [Na⁺] = 0.1 M, containing 3% (v/v) EtOH-and 0.8% NaOH). Gizzerosine was measured by the post-column reaction of OPA and fluorometric detection. Recovery of gizzerosine added to fish meal was over 90% and the detection limit was 1 ppm.

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A precursor of salmon calcitonin I (SCT) was produced in Escherichia coli transformed by recombinant plasmids. A double-stranded DNA coding for SCT-Gly, preceded by ATG and followed by tandem stop codons, was constructed using a combination of chemical synthesis and enzymatic assembly. The gene for the N-terminal portion of metapyrocatechase (C23O) and its preceding ribosome binding site derived from Pseudomonas putida were fused to the synthetic gene. Introduction of this fragment into E. coli resulted in the synthesis of the fusion protein at high efficiency under the control of the tac promoter. After cleavage of the protein with cyanogen bromide, SCT-Gly was purified to homogeneity by gel filtration and by reverse phase chromatography. The structure of the peptide was confirmed by amino acid composition and sequencing analyses. The hypocalcemic activity of the bacterial product was estimated as about one-seventh of that of SCT.

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Plasma proteins were separated into five fractions by ion-exchange chromatography, and then the emulsifying properties and heat denaturation of the fractions were investigated. Serum albuminrich and γ-globulin-rich fractions were obtained, respectively. A solution of each fraction (1% w/v, pH 7.0) was heated at 80°C for 30min. The gel filtration patterns indicated that high molecular weight polymers arose upon heat treatment in all fractions. The emulsifying activity index (EAI) of all fractions, except those containing γ-globulin, increased on heat treatment. A solution of γ-globulin formed a gel and it lost its emulsifying activity. It was shown that γ-globulin plays a predominant role in the decrease in emulsifying activity of plasma proteins at neutral pH during heat treatment and that the removal of γ-globulin from the plasma proteins effectively prevents the decrease in emulsifying activity under these conditions.

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One monoclonal antibody (MoAb) highly specific for human hemoglobin, KM-371, was generated by a unique immunization procedure using mice rendered tolerant to bovine hemoglobin.
KM-371 strongly reacted with human hemoglobin, but did not with bovine, horse, goat, sheep, rabbit, porcine, chicken, and fish hemoglobins. Human hemoglobin was able to be quantitatively measured in the range 0.01 - 200 μg/ml by a sandwich ELISA using KM-371 and biotinylated KM-371. By immunostaining using KM-371, 20ng of human hemoglobin could be detected on a nitrocellulose membrane.
These results suggest that KM-371 would be a useful MoAb in the test of occult bloods in faeces for diagnosing colorectal carcinoma without a meat diet.

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The desmutagenic activities of some vegetable and fruit juices to the mutagenicity of 2-tert-butyl-p-quinone (t-BQ) were assayed by the Ames test using Salmonella typhimurium TA 100. t-BQ is a strong mutagen and is produced from butylated hydroxyanisole when treated with nitrite under acidic conditions. The juices of sweet pepper, lemon, tomato, orange, strawberry, melon, and kiwi fruit reduced the mutagenicity of t-BQ, the desmutagenic activities being proportionally related to the content of the sulfhydryl group contained in these juices. The authentic sulfhydryl compounds, glutathione, pantetheine and dithiothreitol, were then tested for their desmutagenicity against t-BQ by the induced-mutation frequency method, and they were proved responsible for the desmutagenicity. Glutathione reduced half of the t-BQ to 2-tert-butyl-hydroquinone during the desmutagenic reaction, the other half being suggested to have been a conjugated compound between glutathione and t-BQ.

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A bacterium that stereospecifically produces L-valine from 5-isopropylhydantoin was isolated from soil. It was identified as Bacillus brevis and given the number AJ-12299. L-Valine productivity from L-, D- or DL-5-isopropylhydantoin by B. brevis AJ-12299 was rather low because this bacterium had L-valine degrading-activity. In contrast, the productivity was improved by a mutant the L-valine degradation pathway of which was genetically blocked, and the 5-isopropylhydantoin consumed was stoichiometrically converted to L-valine. The optimal temperature and pH of the reaction were 30°C and 7.0-7.5. The enzyme involved in the reaction was inducible and was strongly induced by the addition of 5-isopropylhydantoin. In addition to L-valine production, this bacterium also produced various aliphatic and aromatic L-amino acids from the corresponding 5-substituted hydantoins.

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The mechanism of Stereospecific production of L-amino acids from the corresponding 5-substituted hydantoins by Bacillus brevis AJ-12299 was studied. The enzymes involved in the reaction were partially purified by DEAE-Toyopearl 650M column chromatography and their properties were investigated. The conversion of DL-5-substituted hydantoins to the corresponding L-amino acids consisted of the following two successive reactions. The first step was the ring-opening hydrolysis to N-carbamoyl amino acids catalyzed by an ATP dependent L-5-substituted hydantoin hydrolase. This reaction was Stereospecific and the N-carbamoyl amino acid produced was exclusively the L-forrn. N-Carbamoyl-L-amino acid was also produced from the D-form of 5-substituted hydantoin, which suggests that spontaneous racemization occurred in the reaction mixture. In the second step, N-carbamoyl-L-amino acid was hydrolyzed to L-amino acid by an N-carbamoyl-L-amino acid hydrolase, which was also an L-specific enzyme. The ATP dependency of the L-5-substituted hydantoin hydrolase was supposed to be the limiting factor in the production of L-amino acids from the corresponding 5-substituted hydantoins by this bacterium.

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A simple and rapid spectrophotometric method, based upon the UV absorption of NADH, for the measurement of putrescine by the combined use of aminobutyraldehyde dehydrogenase (EC 1.2.1.19) and putrescine oxidase (EC 1.4.3.10) was established. Simplified purification procedures for the analytical use of aminobutyraldehyde dehydrogenase of Pseudomonas putida and putrescine oxidase of a newly isolated Gram-positive soil bacterium were developed. When aminobutyraldehyde dehydrogenase alone was used, the amount of 4-aminobutyraldehyde and the absorbance of NADH formed during the enzyme reaction had a precisely linear relationship in the range from 2 to 80 nmol of 4-aminobutyraldehyde. A comparable accuracy and sensitivity was obtained when a combination of putrescine oxidase and aminobutyraldehyde dehydrogenase was used to measure putrescine.

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Kynurenine aminotransferase from a yeast, Hansenula schneggii, has been found to catalyze the deamination of an olefinic amino acid, L-vinylglycine, to form α-ketobutyrate and ammonia. The maximum rate of deamination was 0.17 μmol/mg/min at 25°C (pH 8.0), which is approximately 1 % of the rate of transamination between L-kynurenine and α-ketoglutarate. Concomitantly with the catalysis, the enzyme lost both the deaminase and aminotransferase activities in a time-dependent manner. The inactivation was irreversible and followed pseudo-first-order kinetics at various concentrations of L-vinylglycine. The Michaelis constant for L-vinylglycine in the inactivation reaction was essentially the same as that in the deamination. These results indicate that the two reactions proceed through a common intermediary complex, and L-vinylglycine acts as a suicide inactivator for the enzyme. The apoenzyme neither catalyzed the deamination nor was inactivated by L-vinylglycine. The enzyme also catalyzes the γ-addition reaction of L-vinylglycine in the presence of alkanethiols producing the corresponding S-substituted homocysteines.

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The rates of shrinkage at constant temperature, and growth under a temperature rise below 100°C, of bubbles entrained in wheat flour dough were analyzed and compared with those of a bubble in water. The rate of shrinkage of bubbles in flour dough was controlled by the diffusion of dissolved air from the surface of bubbles to the bulk of flour dough. The apparent diffusion coefficient of the dissolved air in wheat flour dough with the water fraction of 0.49 calculated from the shrinkage of bubbles, was (3.2±1.5) × 10^-11 m²/sec (19°C), and (6.4±2.0) × 10^-11 m²/sec (42°C). However, the growth behavior of bubbles in flour dough under a temperature rise was very different from that predicted from the diffusion theory. The critical radius of bubbles to grow was larger than that estimated from the diffusion theory. The mechanism of growth of bubbles in wheat flour dough, which was different from that of a bubble in water, is a subject that needs to be clarified.

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A mixed culture composed of two Pseudomonas strains, designated as KKL101 and KKS102, was isolated from soil. This mixed culture had an enhanced ability to degrade various polychlorinated biphenyls (PCBs) which include highly chlorinated components. They did not grow individually on the mineral salts medium supplemented with a highly chlorinated PCB (PCB48, a mixture of mainly tetrachlorobipheny1) and biphenyl. When the spent medium of KKL101 was added to the washed cell preparation of KKS102, however, the latter grew on these carbon sources, producing yellow compounds which were identified as metabolic intermediates of the carbon sources, biphenyl and PCBs. These results suggest that KKL101 produces a growth factor(s) essential for KKS102 to grow on PCBs and that the growth of KKL101 is supported by the metabolic intermediates produced by KKS102. It appears that these two bacterial strains have a symbiotic relationship. From the analysis of the degradation products of various PCB congeners, it was found that strain KKS102 degrades a wide range of PCBs which have been considered to be refractory to biological degradation.

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The effects of artificial food dyes on the mutagenicity of carcinogenic mutagens were examined using the Salmonella/microsome system. Indigocarmine (IC), an indigoid dye widely used for coloring foods and for clinical tests, enhanced the mutagenic activity of Trp-P-1, a carcinogenic pyrolysate of tryptophan, depending on the dose of IC. His⁺ revertants of TA 98 induced by Trp-P1 were two to four times greater in the presence of 10 to 50 μg/plate of IC than those in the absence of IC.
IC also enhanced the mutagenicity of Trp-P-2, another carcinogenic pyrolysate of tryptophan, while the activities of other mutagens such as MNNG, 4-NQO, AF-2, BP, Glu-P-1 were not affected.

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L-Methionine γ-lyase (EC 4.4.1.11) catalyzes α, β-elimination of L-2-amino-3-(N-methylamino)propionic acid and L-2-amino-3-(N-hydroxyethylamino)propionic acid to yield pyruvate, ammonia, and the corresponding amines. These amino acids also undergo the enzymatic β-replacement reaction with thiols to produce the corresponding S-substituted cysteines. Thus, L-methionine γ-lyase cleaves a C-N bond in addition to C-S, C-Se, and C-O bonds at the β position of amino acids by elimination and replacement reactions. A linear relationship between the reactivity, (log( V_max/Km) and the pKa value of the conjugated acid of the leaving group has been found for Se-methyl-L-selenocysteine, S-methyl-L-cysteine, and O-methyl-L-serine. However, L-2-amino-3-(N-methylamino)propionic acid has shown lower reactivity than that expected from the pKa value of methylammonium ions.

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The ddh gene of Corynebacterium glutamicum encoding meso-diaminopimelate (meso-DAP)-Ddehydrogenase (DDH) involved in the lysine biosynthesis was cloned in a DAP auxotroph (dap D4) of Escherichia coli by complementation of the DAP auxotroph. Deletion analysis revealed that a - 1.7-kb XhoI-KpnI fragment contained the ddh structure gene. The specific activity of DDH was increased fourteen-fold when C. glutamicum was transformed with a recombinant plasmid harbouring the cloned ddh gene. Furthermore, the ddh gene has been sequenced [S. Ishino et al., Nucleic Acids Res., 15, 3917 (1987)] and some properties of the ddh gene are discussed.

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Fifty-five new five-membered cyclic organophosphorus compounds including oxazaphospholidines, thiazaphospholidines, and Oxathiaphospholanes were synthesized, which have substituents at 4- or /and 5-positions besides at the 2-position. The thiazaphospholidines showed the highest insecticidal activity followed by Oxathiaphospholanes and Oxazaphospholidines. The position preference of substituents in insecticidal activity was most obvious in the Oxazaphospholidines. It was preferable for insecticidal activity to have the substituent near the more basic atom: the 4-position for thiazaphospholidine and oxazaphospholidine, the 5-position for oxathiaphospholane, with the exception of 4- or 5-phenyl oxazaphospholidine.

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