Alkaline invertase activity was hardly detectable in immature sugar beet roots, but appeared when the roots began to develop and simultaneouly to synthesize sucrose, and thereafter, increased parallel with sucrose accumulation. Conversely, acid invertase activity was very high in immature roots, but rapidly decreased before sucrose was stored, and was hardly detectable in mature roots.
Alkaline invertase was partially purified from mature roots by procedures including ammonium sulfate fractionation, DEAE-cellulose column chromatography, Sephacryl S-300 gel filtration, and ECTEOLA-cellulose column chromatography. Alkaline invertase consisted of two forms (enzymes I and II) which were separated by DEAE-cellulose column chromatography. Relative molecular weights of both enzymes obtained by gel filtration on Sephacryl S-300 were the same, and were estimated to be 280, 000. Their pH optima were in the vicinity of 8.0. The Km value for sucrose of enzyme I was 33.3 mM and enzyme II showed a biphasic curve in Lineweaver-Burk plots. Both enzymes I and II hydrolyzed sucrose, but could not hydrolyze raffinose, maltose, or p-nitrophenyl-α-D-glucoside. Changes in their activities during development of roots showed different patterns. The roots had a high activity of enzyme I during sucrose accumulation and the enzyme rapidly decreased when sucrose reached a constant level, while the level of enzyme II activity was approximately constant.

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Streptococcus lactis subsp. diacetylactis 3022 produced 5.4 times the amount of diacetyl on 24 hours incubation in 30% RSM medium supplemented with 1 mM Cu²⁺, compared to that in the medium without Cu²⁺. However, the citrate utilization in the medium with Cu²⁺ was considerably repressed. On the other hand, the diacetyl formation activity of the cells was markedly stimulated by adding Cu²⁺, Fe²⁺, Fe³⁺, Co²⁺ and Mo⁶⁺ to the reaction mixture. Cu²⁺ and Co²⁺ also stimulated citrate lyase. Cu²⁺ was the most effective stimulator for these activities. These metal ions had no effects on citrate uptake activity or diacetyl reductase activity.
After the addition of MRS medium with and without Cu²⁺ to a culture incubated at 30°C for 24 hours, the cells in the medium with Cu²⁺ produced.a larger amount of diacetyl than those in the medium without Cu²⁺. On the contrary, the citrate utilization of the former cells was inferior to that of the latter. From these results, it appeared that diacetyl reductase activity was lowered by citrate remaining in the medium with Cu²⁺ and that the metal ion in the medium stimulated the activities of diacetyl formation and citrate lyase.

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Plasmid pCYG97 was constructed, which carried the kanamycin (G418) resistance gene of Tn903 and a DNA fragment from Acremonium chrysogenum. The DNA fragment from A. chrysogenum functions as an autonomously replicating sequence (ARS) in Saccharomyces cerevisiae. The transformation of A. chrysogenum and S. cerevisiae with pCYG97 DNA was attempted. Transformants resistant to the antibiotic, G418, were obtained from both strains after treatment of protoplasts with polyethylene glycol. The transformation efficiency of A. chrysogenum was lower than that of S. cerevisiae. The DNA sequence of the A. chrysogenum DNA fragment of pCYG97 was determined. The fragment contains multiple copies of sequences that have at least 10 out of 11 bases of homology to a previously reported core consensus sequence of S. cerevisiae, (A/T)TTTAT(A/G)TTT(A/T).

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Hybridomas that produce two monoclonal antibodies (MoAbs) to salmon somatotropin (sST) and two MoAbs to salmon prolactin (sPRL) were established. Two MoAbs to sST, designated KM166 and KM167, reacted specifically with sST and did not react with sPRL, proteins derived from host Escherichia coli, or bovine serum albumin. KM200 and KM212 raised against sPRL were specific for sPRL. Using these MoAbs we have developed a sandwich-type enzyme immunoassay (ELISA) system for sST or sPRL. With these assays, sST and sPRL could be quantitatively measured in the range of 0.16-4μg/ml and 3.1-200 μg/ml, respectively. The immunoaffinity column using KM200 adsorbed specifically sPRL. By elution with 7M urea/1 M NaCl, the sPRL was eluted with a high recovery.

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A gas-liquid chromatographic method was applied to the determination of anomeric forms of isomaltose and glucose produced by Arthrobacter globiformis isomalto-dextranase and glucodextranase. The anomeric forms of products released from isomaltotriose, panose and dextran were quantitatively determined. The isomalto-dextranase that was also capable of splitting the α-1, 4-glucosidic linkage of panose was found to exclusively produce α-isomaltose from these substrates, and the glucodextranase, β-glucose.

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Enzymes I and II, which have a high soymilk-clotting activity, produced from K-295G-7 were purified by chromatographies on Sephadex G-100, CM-cellulose, hydroxylapatite, and 2nd Sephadex G-100.
The two purified enzymes were found to be homogeneous by polyacrylamide gel electrophoresis (PAGE) at pH 4.3. The molecular weights of enzymes I and II were 28, 000 and 29, 500 by SDS-PAGE, and their isoelectric points were 9.22 and 9.45, respectively. Enzymes I and II coagulated soymilk optimally at 65°C and were stable up to 45°C. Both enzymes were most active at pH 5.8, for soymilk coagulation between pH 5.8 to 6.7, and were stable with about 50-100% of the original activity from pH 5 to 10.
Each of the purified enzymes was a serine protease with an optimum pH of 9.0 for soy protein isolate (SPI) and casein digestions, because these enzymes were inhibited completely by diisopropylfluoro-phosphate (DFP).
The soymilk-clotting activity to proteolytic activity ratio of the enzyme II was 3 times higher than that of enzyme I. Enzymes I and II were more sensitive to the calcium ion concentration in soymilk than bromelain is.

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A new conjugate of hydroxyabscisic acid, tentatively named MeHMG-HOABA, along with a known conjugate, β-hydroxy-β-methylglutarylhydroxyabscisic acid (HMG-HOABA), were isolated from immature seeds of Robinia pseudacacia and determined. Evidence for the occurrence of MeHMG-HOABA as a natural metabolite, and not as an artifact, was provided by desorption chemical ionization (DCI) and secondary ion mass spectrometry (SIMS) in conjunction with the technique of linked scanning at constant B/E. The mass spectrometric technique allows the detection and characterization of the conjugates to be analysed even in a crude plant extract.

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Two mechanisms of ice crystal growth were found in a batch crystallizer with an external cooler, that contained a large amount of ice crystals. With the first mechanism, the ice crystals grew larger by the usual kind of growth, governed by heat or mass transfer resistance, and with the second, the ice crystals agglomerated and the agglomerate fused into a very large ice crystal (1-3mm in diameter). The conditions in which the second mechanism prevails were investigated extensively. The second mechanism occurred not because of the high concentration of ice crystals in the crystallizer but because of long residence time. Large ice crystal agglomerates were not produced when extremely small ice crystals were formed in the crystallizer at the start of the experiment.

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Four types of β-xylosidases from a concentrated culture filtrate of Penicillium wortmanni IFO 7237, designated as xylosidase-1, -2, -3, and -4 were purified to homogeneity on SDS polyacrylamide gel electrophoresis by an alcohol precipitation, DEAE-Sephadex A-25 ion exchange chromatography, and isoelectric focusing. The molecular weights of xylosidase-1, -2, -3, and -4 were estimated to be 110, 000, 195, 000, 210, 000, and 180, 000 respectively and their isoelectric points to be 3.7, 4.28, 4.6, and 4.8. The pH optima of β-xylosidase activities were from 3 to 4.5. The optimum temperature for enzyme activities was from 55°C to 65°C. On the enzymic hydrolysis of phenyl β-Dxyloside, the reaction product of each enzyme was found to be β-D-xylose with retention of configuration. All the four β-xylosidases were free of α-xylosidase and β-glucosidase activities. All the enzyme activities of four β-xylosidases were strongly inhibited by Hg²⁺ and N-bromosuccinimide. With respect to the hydrolysis patterns and HPLC analysis of hydrolyzates from xylooligosaccharides, xylosidase-2 was totally different from other three as a distinct enzyme. Xylosidase-1 was also in a separate group although xylosidase-3 and -4 showed closely related action patterns as a different group.

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The distribution of the methylcitric acid cycle and the modified β-oxidation pathway for propionate catabolism was surveyed in yeasts and filamentous fungi, mainly by comparing the activities of the key enzymes. All the six tested species of filamentous fungi belonging to five genera and 21 species of yeasts belonging to eleven genera were found to catabolize propionate through the methylcitric acid cycle, with the exception of Candida rugosa and one group of strains of C. catenulata, which catabolize propionate through the β-oxidation pathway. From the observed diversity of propionate catabolism among closely related strains or species, it was assumed that different minor pathways evolved from universal metabolic pathways, such as the citric acid cycle and the β-oxidation pathway for fatty acids, in later stages of an evolutionary history.

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In order to investigate the effect of leucine residues on the taste of peptides, some oligo peptides containing leucine residues were synthesized and their taste was evaluated. The hydrophobicity of leucine residues markedly caused the bitterness of peptides and stronger bitterness was always found when a leucine residue was located at the C-terminus of peptides. The possibility of 2 binding sites between the bitter peptides and the bitter taste receptors of the gustation cells was postulated.

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Crocin, picrocrocin, and safranal as the major secondary metabolites are important for the high quality of spice saffron. Crocin and picrocrocin were detected in stigma-like structures proliferated in vitro. Safranal appeared after heat treatment. The contents and relative ratio of these substances in the stigma-like structures were similar to those in intact young stigmas, indicating that these stigma-like structures showed not only morphological but also biochemical similarity to the intact stigmas.

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Two types of glycerol dehydrogenase (GDH) were found on DEAE-cellulose column chromatography of cell-free extracts of methylotrophic yeasts. One type, designated as GDH I, showed only the reductive activity which was detected in the reaction system containing dihydroxyacetone and NADH, at pH 6.0. The other type, designated as GDH II, showed the oxidative activity which was detected in the system containing glycerol and NAD⁺, at pH 9.0, together with the reductive activity.
Candida boidinii No. 2201, which possesses the phosphorylative pathway for glycerol dissimilation, had only GDH I when grown on glycerol or methanol as the carbon source. Hansenula ofunaensis, which has the oxidative pathway, had both GDH I and GDH II when grown on glycerol, but only GDH I when grown on methanol. Hansenula polymorpha DL-1, which has both pathways, had both GDH I and GDH II when grown on glycerol or methanol.

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A considerable amount of menaquinone (MK)-4 was found in cells of a 1-hydroxy-2-naphthoate-resistant mutant, strain HNA 250-15, which was derived from Flavobacterium sp. 238-7, in which MK-6 is the major isoprenoid quinone. The MK-4 productivity was further improved by making the mutant resistant to usnic acid and menadione. The amount of MK produced by the resultant mutant, strain K³-15, produced 125.4mg/l of culture broth and 12.8mg/g of dry cell weight, in the ratio of MK-4 and MK-6 of 6:1, under the optimal culture conditions in the presence of cedar wood oil.

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When hexavalent chromium (Cr⁶⁺) tolerant Pseudomonas ambigua G-1 was cultivated in nutrient broth containing 150ppm Cr⁶⁺, the Cr⁶⁺ content of the broth rapidly decreased. The Cr⁶⁺ reducing enzyme found in a cell-free extract of P. ambigua G-1 required NADH but not NADPH as a hydrogen donor for the reduction of Cr⁶⁺. The specific activities of cell-free extracts of several Cr⁶⁺ sensitive mutants derived from P. ambigua G-1 showed decreases to one fourth to one tenth of that of P. ambigua G-1. Glucose protected the Cr⁶⁺ reducing enzyme against inactivation on dialysis.

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The microorganisms that reduce benzil to optically active benzoin were screened. Xanthomonas oryzae IAM 1657 was selected as the best strain, which resulted in the formation of (R)-(-)-benzoin. This biochemical reduction was applied to other 1, 2- and 1, 3-diketones to find that only 1, 2-diarylethanediones were reduced smoothly to afford the corresponding ketols.

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A thermophilic alkalophile (IC strain) which can grow well in an alkaline medium at over 55°C was isolated from soil samples, and identified as Bacillus licheniformis; its growth on a neutral medium was, however, very poor. This strain was able to grow at 37°C as well as at 55°C, but the specific growth rate at 55°C was about twice as high as that at 37°C under alkaline conditions.
The intracellular pH remained below 9.5 when Na⁺ was present in the medium. Na⁺ stimulated the alanine uptake by cells or membrane vesicles, but was not required ATP synthesis.
Intracellular enzymes were stable on heat treatment up to 60°C. The residual activity of enolase after heating at 60°C for 10min was about 80%. Cytochrome oxidase in membrane vesicles was completely stable up to 58°C for 30min. These enzymes were also resistant to SDS treatment, more than 50% of their activities remaining at 5% SDS.

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Heat evolution during the growth of Escherichia coli in a stationary culture on bouillon medium was continuously monitored with a conduction-type batch calorimeter at different pHs and temperatures. The growth thermograms were found to be reproducible within percent errors of ±2.1%, ±0.8% and ±1.5% for the peak time of a thermogram, the peak height and the total heat evolution, respectively. The mean heat evolution for the formation of a unit E. coli cell was ω=(1.69±0.08)×10^-8 J cell^-1 at pH 6.2 and 37°C. The mean heat evolution rate per unit cell during growth was q=3.6 pw cell^-1, which was consistent with values calculated for other microbial cells. The growth rate constant calculated on kinetic analysis of the growth thermograms was μ = 0.532±0.068 hr^-1 at pH 6.2 and 37°C. The pH dependence of the growth rate constant showed that the growth activity of E. coli cells on bouillon medium is maximum in the pH range of 5.5 to 6.5. From the temperature-dependent variations in the growth rate constant, the apparent activation energy of E. coli growth was found to be E_a = 65.3±7.1 kJ mol^-1.

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The effects of streptomycin, tetracycline and Chloramphenicol on the growth of Escherichia coli were studied quantitatively in a conduction-type batch calorimeter at pH 6.2 and 37°C. Change in the growth thermograms with increasing drug concentrations in the medium were analyzed with a kinetic model of non-competitive inhibition.
The number of drug molecules needed to inactivate a unit viable cell, m, was estimated to be 1.2±0.1, 0.7±0.1 and 1.3±0.1 for streptomycin, tetracycline and Chloramphenicol, respectively. With the assumption that the drug binding sites are all identical, the microscopic dissociation constant per binding site, K_i for the drugs was found to be 0.19, 0.43 and 0.94 μmol dm^-3 for streptomycin, tetracycline and Chloramphenicol, respectively. With these m and K_i values, drug potency curves were drawn for the three drugs.

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Selenium contents of rice grown in Japan were analyzed by various methods. For the comparison of analytical methods, both fluorometry and neutron activation analysis gave reliable results. When two neutron activation analyses, measurements of activated ⁷⁵Se and ^77mSe, were used, average selenium contents o.f the 28 brown rice samples grown in Hokkaido, Hokuriku, Chugoku, Shikoku, and Kyushu were 32 ng/g dry weight (range: 13-83 mg/g) by ⁷⁵Se and 36 ng/g (range: 16-88 ng/g) by ^77mSe. From the data obtained, we concluded that the selenium content of brown rice grown in Japan was 30-40ng/g on the average.

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Contents of polyamines and 1-aminocyclopropane-1-carboxylic acid (ACC) in Hiproly barley callus were examined under different culture conditions. After auxin withdrawal, the contents of free polyamines changed conversely to the contents of ACC. In the absence of auxin, incorporation of L-[3, 4-¹⁴C]methionine into polyamines and the activity of S-adenosylmethionine decarboxylase (SAMDCase) in the callus increased, then remained stable, but incorporation of L-[3, 4-¹⁴C]methionine into ACC, precursor of ethylene and ACC synthase activity once declined and increased again.
Aminooxyacetic acid (AOA) affected the increase in the levels of polyamines in the callus. 1-Aminoisobutyric acid (AIB) had a slight effect on the polyamine production. The incorporation of L-[3, 4-¹⁴C]methionine into ACC and ACC synthase activity were inhibited by AOA, but not by AIB. AOA stimulated the activity of SAMDCase, and also enhanced the incorporation of L-[3, 4-¹⁴C]methionine into polyamines in the callus. Methylglyoxal-bis(guanylhydrazone) (MGBG) greatly enhanced the ACC production. The rate of incorporation of L-[3, 4-¹⁴C]methionine into ACC and ACC synthase activity in the callus were significantly enhanced by MGBG. MGBG strongly inhibited SAMDCase activity and the incorporation of L-[3, 4-¹⁴C]methionine into polyamines. Moreover, the synthesis of polyamines was inhibited by MGBG.
These results suggested that in Hiproly barley callus ACC production has an important effect on changes in the polyamine levels, and that polyamine and ethylene biosynthetic pathways are regulated by competition against each other.

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The purification of yeast glycogen phosphorylase [EC 2.4.1.1] was improved by ethanol precipitation and affinity chromatography on a glycogen-Sepharose column. The purified enzyme gave a single protein band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and had a subunit molecular mass of 100 kDa. Gel electrophoresis also showed that the major activity of native phosphorylase was ascribed to a dimer of 203 kDa, which was agreed with the value obtained by gel filtration on Sephadex G-200. The yeast phosphorylase showed a high affinity for AMP-Sepharose, whereas the enzyme was specifically inhibited by AMP. This inhibition was competitive with respect to the substrate glucose 1-phosphate and gave a Ki value of 9.3 mM. Activation of the crude extract by phosphorylation with an endogenous phosphorylase kinase indicated that the yeast phosphorylase occurred in a mixture of phosphorylated and non-phosphorylated forms.

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Thirty-six volatile compounds were positively identified in the dichloromethane extract of an aqueous solution of L-cysteine that was irradiated with UV light at 253.7 nm for 24 hr. The irradiated solution was colorless but has a cooked meat-like flavor. The compounds identified were thiophenes, pyrazines, thiazoles, thiazolines, thiazolidines, and polymethylene sulfides. 2-Methylthiazole was found in the largest quantity, approximately 40% of the extract. Proposed photochemical reactions of cysteine included Strecker degradation, isomerization, dimerization, and homolytic fission of C-C, C-S, or S-H bonding.

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Free amino acids and S-methylmethionine (MMS, an anti-ulcer factor, Vitamin U) in green tea extracts were simultaneously determined with an HPLC-amino acid analyzer using lithium citrate buffers.
Rapid analysis of MMS and free amino acids was achieved with a high resolution column, MCI Gel CK-10U 0.46φ × 15cm, within ISOmin. MMS in the column eluates was identified as dimethyl sulfide by a gas-chromatographic method with a flame photometric detector. The contents of MMS and free amino acids in various green teas were determined and compared with respect to the quality of commercial teas, blended teas and non-blended teas, and the place of cultivation of the tea. The described method is rapid and useful for checking the quality of green tea.

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The cultural conditions were investigated for a Brevibacteriumflavum mutant, No. 2-190, with a low level of citrate synthase (CS) and with feedback-resistant phosphoenoipyruvate (PEP) carboxylase and aspartokinase (AK). The productivity was increased from 28 to 38 g/l (as the HCl salt) with a medium containing 10% glucose. From this strain, pyruvate kinase (PK)-defective mutants were derived and selected as to the inability to grow on ribose. Among them, strain KL-18 showed higher lysine productivity than the parent under all cultural conditions tested, and produced 43 g/l of lysine, at maximum. A lysine-producing mutant, No. 536-4, with a feedback-resistant AK was derived from PK-defective strain KH-21 which had low CS activity and a feedback-resistant PEP carboxylase. The mutant was isolated by a new selection method, that is, on the basis of resistance to α-amino-β-hydroxyvaleric acid, a threonine analogue plus lysine. In this strain, HD had been altered so as to become feedback-resistant at the same time, resulting in the byproduction of threonine and isoleucine. The total amount of these aspartate family amino acids was higher on molar basis than that of lysine produced by strain No. 2-190.

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Aspergillus kawachii α-amylase [EC 3.2.1.1] 1 and II were purified from shochu koji extract by DEAE Bio-Gel A ion exchange chromatography, Sephacryl S-300 gel chromatography (pH 3.6), ω-amino dodecyl agarose column chromatography and Sephacryl S-200 gel chromatography. By gel chromatography on a Sephacryl S-300 column, the molecular weights of the purified α-amylase I and II were estimated to be 104, 000 and 66, 000, respectively. The isoelectric points of α-amylase I and II were 4.25 and 4.20, respectively. The optimal pH range of α-amylase I was 4.0 to 5.0, and the optimum pH of α-amylase 'II was 5.0. The optimum temperatures of both α-amylases were around 70°C at pH 5.0. Both α-amylases were stable from pH 2.5 to 6.0 and up to 55°C, retaining more than 90% of the original activities. Heavy metal ions such as Hg²⁺ and Pb²⁺ were potent inhibitors for both α-amylases.

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A drug-resistant mutant, No. 4-23-11, which had been derived from Penicillium brevicompactum ATCC 16024, was cultured in a liquid medium for the production of mycophenolic acid (MPA) in the presence and absence of various adsorbents, that is, celites, zeolites, aluminas, talc, silica, charcoals, carbon blacks, natural graphite and carbonaceous mesophase spheres. In the absence of an adsorbent, MPA production (0.2-4.8g/l) and the size of mycelium pellets (5-0.5mm) markedly depended on the concentration of spores inoculated (10⁴-10⁷/ml), whereas in the presence of one of these adsorbents, small pellets (smaller than 1 mm in diameter) were formed and the high production of MPA (4.5-5.4 g/l) was observed, independently of the spore concentration between approximately 10⁴-10⁷/ml. Microscopic observation of the pellets revealed that numerous particles of the adsorbents adhered to the surface of the hyphae. These results suggest that the adsorbents might interfere with the adhesion of hyphae to each other and thus retard the formation of large pellets.

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Penicillium brevicompactum ATCC 16024 produced 1.7g/l of mycophenolic acid (MPA) in the culture medium. Various drug-resistant mutants, showing resistance to such as polyene antibiotics, chemotherapeutic agents, redox indicator and surfactants, were derived from the fungus. Most of the mutants produced 2.0-2.5 g/l of MPA. A clofibrate and dodecyltrimethylammonium chloride double resistant mutant, No. 4-23-11, produced 4.7 g/l of MPA. A monofluoroacetic acid resistant strain, No. 5-1, derived from No. 4-23-11 produced 5.3 g/l of MPA.
A methionine auxotroph, M-1, derived from ATCC 16024, produced 4.0 g/l of MPA. A glutamate auxotroph, G-42, derived from strain No. 4-23-11 produced 5.8 g/l of MPA. G-42 grew on L-aspartate instead of L-glutamate, and showed one-third the pyruvate carboxylase activity of the parent. Another glutamate auxotroph, G-78, did not produce MPA but accumulated 1.5 g/l of acetate in the culture medium, and showed one-fifth the citrate synthase activity of the parent strain.

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An extracellular phospholipase D from Actinomadura sp. Strain No. 362 was purified about 430-fold from the culture filtrate. The purified enzyme preparation was judged to be homogeneous on polyacrylamide gel electrophoresis. The molecular weight and isoelectric point of the enzyme were estimated to be about 50, 000-60, 000 and 6.4, respectively. The enzyme was most active at pH 5.5 and 50°C in the presence of Triton X-100, but showed the highest activity at pH 7.0 and 60-70°C in its absence. The enzyme was stable up to 30°C at pH 7.2 and also stable in the pH range of 4.0 to 8.0 on 2hr incubation at 25°C. With regard to substrate specificity, this enzyme hydrolysed lecithin best among the phospholipids tested. It was activated by Fe³⁺, A1³⁺, Mn²⁺, Ca²⁺, diethyl ether, sodium deoxycholate and Triton X-100, but was inhibited by cetyl pyridinium chloride and dodecylsulfate.

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The lipase purified from Pseudomonas fragi 22.39B hydrolyzed not only triglycerides but also synthetic esters such as Tween, Span and methyl oleate. Of the saturated monoacid triglycerides tested, tributyrin was hydrolyzed most quickly. The lipase did not produce 1, 3-diolein as a hydrolysis product from triolein. The addition of the Ca²⁺ ion to the reaction mixture promoted the hydrolysis rate for triglycerides and monoesters with longer-chain fatty acids (C₁₄, C₁₆, C₁₈). The enzyme could hydrolyze various kinds of natural fats and oils, and the extent their hydrolysis reached above 90%.

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Inhibition of a constitutive aromatic L-amino acid decarboxylase from Micrococcus percitreus AJ 1065 was investigated to obtain some information about the reaction mechanism of the enzyme and the physiological role of the enzyme in the bacterium. Decarboxylation of L-tryptophan by the enzyme was inhibited by the other substrates and by aromatic amines such as β-phenylethylamine, tyramine, dopamine, epinephrine, norepinephrine, and 3-indoleacetamide and 3-indolealdehyde which correspond to or are related to the substrates of the enzyme. To study the mechanism of inhibition by 3, 4-dihydroxyphenyl-L-alanine, the nonenzymatic reaction product of pyridoxal 5'-phosphate and 3, 4-dihydroxyphenyl-L-alanine was prepared and was identified as 7, 8-dihydroxy-1-[2'-methyl-3'-hydroxy-5'-phosphohydroxymethyl-4'-pyridyl]-3-carboxy-l, 2, 3, 4-tetrahydroisoquinoline.

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The trisaccharide segment of the phenolic glycolipid I of Mycobacterium leprae was synthesized effectively in the form of p-(2-methoxycarbonylethyl)phenyl glycoside by the condensation of p-(2-methoxycarbonylethyl)phenyl 4-O-benzyl-3-O-methyl-α-L-rhamnopyranoside and 2, 3-di-O-methyl-4-O-(2, 4-di-O-acetyl-3, 6-di-O-methyl-β-D-glucopyranosyl)-α-L-rhamnopyranosyl chloride in the presence of silver triflate and 1, 1, 3, 3-tetra-N-methylurea, and subsequent selective deprotection. This was then coupled to BSA by the acyl azide method, giving NT-P-BSA. The NT-P-BSA showed very high reactivity and specificity to leprosy sera. The trisaccharide-BSA conjugate with a β-linked rhamnosylrhamnose unit (βT-P-BSA) was also synthesized.

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The transformation of Aspergillus oryzae has been achieved with a plasmid carrying the Aspergillus nidulans argB gene coding for ornithine carbamoyltransferase (OCTase). The frequency of transformation was relatively low (0.7 transformants/μg DNA) but the transformed phenotype was extremely stable for many generations without selective pressure.
Southern blot analysis revealed that transformation had occurred by integration of multiple tandem copies of plasmid DNA into the host genome through non-homologous recombination. There was no evidence of the existence of free plasmid in the transformants. The number of integrated copies of the plasmid ranged from 15 to 60. The specific activity of OCTase in the cellfree extract was proportional to the copy number of the plasmid, indicating that most of the integrated argB gene was expressed.

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Thr-Thr-Met-Pro-Leu-Trp, the C-terminal hexapeptide of α_s1-casein, inhibited the angiotensin I-converting enzyme (I₅₀ = 16 μM). Z-Pro-Leu-Trp also inhibited the enzyme (I₅₀ = 18μM). The Pro-Leu-Trp sequence may be important for the inhibitory activity of this hexapeptide. Z-Pro-Val-Trp, which contains Val in place of Leu, inhibited the enzyme more potently (I₅₀=2.9μM).
The antihypertensive activity of this hexapeptide was also investigated. This peptide, when intravenously administered to anesthetized rats at 31.8mg/kg, tended to antagonize the rats' pressor response to angiotensin I.

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α-Substituted benzylamino-s-triazines were synthesized, and their phytotoxic activity and phytotoxic symptom against paddy weeds and transplanted rice seedlings were evaluated. Some of these compounds exhibited potent phytotoxicity against the weeds, high selectivity between the rice and the weeds, and had different phytotoxic properties to atrazine and simetryn. Among these compounds, 2-chloro-4-ethylamino-6-α-methylbenzylamino-s-triazine (2), 2-chloro-4-ethylamino6-α-ethylbenzylamino-s-triazine (3), 2-chloro-4-diethylamino-6-α-methylbenzylamino-s-triazine (17), and 2-chloro-4-diisopropylamino-6-α-methylbenzylamino-s-triazine (19) were found to have high phytotoxic activity and selectivity. The phytotoxic symptom of these compounds was mainly growth inhibition to the weeds. Two of these, the diethylamino (17) and diisopropylamino (19) compounds, showed growth inhibition activity without burning the leaf of rice plants at high doses.

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A highly sensitive and simple chemiluminescent method for the quantitation of lipid hydroperoxides at the picomole level is described. The method is based on detecting the Chemiluminescence generated during the oxidation of luminol by the reaction with hydroperoxide and cytochrome c under mild conditions. A semilogarithmic relationship was observed between the hydroperoxide added and the Chemiluminescence produced. For lipid hydroperoxides, cytochrome c was a most favorable catalyst for generating the Chemiluminescence, rather than cytochrome c heme peptide and horseradish peroxidase. This method had high sensitivity to methyl linoleate hydroperoxide, arachidonic acid hydroperoxide and cholesterol hydroperoxide, but low to t-butyl hydroperoxide, t-butyl perbenzoate, diacyl peroxides (lauroyl peroxode and benzoyl peroxide) and dialkyl peroxides (di-t-butyl peroxide and dicumyl peroxide).

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An Escherichia coli mutant (MX-5) deficient in D-xylose utilization was isolated. The D-xylose uptake and D-xylose isomerase activities of the mutant were much lower than those of the parental strain (C600). The genes responsible for the D-xylose uptake by E. coli were cloned onto vector plasmid pBR322, and the resultant hybrid plasmid was designated as pXP5. Hybrid plasmid pXP5 improved the growth rate of the mutant (MX-5) on D-xylose, and also both the D-xylose uptake and D-xylose isomerase activities of the mutant were recovered when pXP5 was introduced into the mutant cells. Based on these results, it was suggested that one (xylT) of the D-xylose transport genes could be closely linked to the D-xylose isomerase gene (xylA) known to be present at SOmin on E. coli chromosomal DNA.

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