The mechanism of hydrocarbon uptake by a yeast, Candida lipolytica has been studied by mean of the kinetic analysis of substrate assimilation and solubilizing effect observed during growth. The solubility of n-alkanes used as sole source of carbon for the growth is compared with that of other normal paraffins which have not been used as substrate. In any case the solubility of the hydrocarbon used as substrate is greater and we observe a specific solubilizing effect upon this alkane. During growth of Candida lipolytica upon mixture of hydrocarbons, same delays are observed both on n-alkane consumption and solubilizing effect. If we remove one hydrocarbon from fermentation medium, the specific solubilizing effect is lost. This prove the active role of dissolved hydrocarbon in the continuous phase. There is a little probability that growth occurs mainly by cell attachment at hydrocarbon droplet, and a great probability that oil material is uptake by microorganisms from the continuous phase. Solubilization is the first step of hydrocarbon assimilation.

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Purification studies were conducted on DNA polymerase bound to the membrane fraction of E. coli HF 4704. Purified enzyme (Fraction V) required Mg²⁺ and showed an optimun pH of 7.2. Various kinds of salt indicated a stimulative effect at concentrations lower than 0.1M. Fraction V was unstable at an acidic condition (pH 5.0) but was rather stable at an alkaline condition (pH 9.0). The enzyme activity was lost by incubation at 45°C for 30min but was stabilized by the addition of DNA. The enzyme contained exonuclease activity but no endonuclease activity. The enzyme produced only light density DNA of various sizes. The function of this enzyme as considered to fill single stranded region of the double stranded primer DNA.

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Sclerin (SCL) not only elevated the respiratory control ratio and ADP/O ratio in mitochondria isolated from rat liver and some plants, but was effective in maintaining the energylinked functions in these mitochondria during aging. There was a close relationship in the effect of SCL between the liberation of fatty acid and maintenance of the energy-linked functions in mitochondria during aging. The liberation of fatty acid was mainly due to the digestion of mitochondrial phospholipids by endogenous phospholipase. SCL had no effect on the activity of phospholipase and rather raised the level of endogenous phospholipase in mitochondria during aging at 30°C. The activity of phospholipase in mitochondria was inhibited by ATP, but stimulated by DNP. It was supposed that SCL inhibits the activity of phospholipase through ATP or high-energy intermediates which is maintained in mitochondria during aging. SCL had a protective effect on the activity of DNP-activated ATPase in mitochondria stored in the cold, and, at a very low concentration, stimulated the ATP-driven NAD reduction by mitochondria.

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D-Ribose-5-phophate ketol-isomerase (EC 5. 3. 1. 6), D-ribulose-5-phosphate 3-epimerase (EC 5. 1. 3. 1) and n-sedoheptulose-7-phosphate: D-glyceraldehyde-3-phosphate glycolaldehyde-transferase (EC 2. 2. 1 .1) have been partially purified. D-Ribose-5-phosphate ketol-isomerase was purified from spinach by column chromatography with DEAE-cellulose and DEAE-Sephadex A-50; D-ribulose-5-phosphate 3-epimerase was purified from baker's yeast by column chromatography with DEAE-cellulose; and D-sedoheptulose-7-phosphate: n-glyceraldehyde-3-phosphate glycolaldehydetransferase was purified from a Bacillus species No. 102 mutant G3-46-22-6 by column chromatography with DEAE-cellulose. The preparations were used for the determination of the activities of these enzymes in the parent and D-ribose-forming mutants of a Bacillus species.

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Determination of enzyme activities on the non-oxidative section of the pentose phosphate pathway in D-ribose-forming mutants of a Bacillus species revealed that two strains, which were isolated as shikimic acid-requiring mutants, lacked D-sedoheptulose-7-phosphate: D-glyceraldehyde glycolaldehydetransferase (EC 2. 2. 1. 1) and one strain, which was isolated as D-gluconate-non-utilizing mutant, lacked D-ribulose-5-phosphate 3-epimerase (EC 5. 1 .3 .1). These three strains were also found to have a kind of pleiotropic property, hardly growing on D-glucose.

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(±)-Sclerotinin A (Scl. A) showed the same promoting activity as natural (+)-Scl. A, which was isolated as a growth promoting substance of rice seedlings from Sclerotinia sclerotiorum along with sclerin. By the combined use of Scl. A and gibberellin, the synergistic effect on the growth of rice seedlings was noticed as in the case of sclerin. Correlation between the chemical structure and biological activity of Scl. A derivatives and analogs was discussed.

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Vitamin B₁₂-dependent methionine synthetase (N⁵-methyltetrahydrofolate-homocysteine B₁₂-methyltransferase; EC 2. 1. 1. 13) was partially purified from two different types of photo-synthetic bacteria, Chromatium D and Rhodospirillum rubrum.
Chromatium D, which does not produce vitamin B₁₂, possessed apomethionine synthetase when grown in the absence of the vitamin. Partially purified apoenzyme was converted to holoenzyme efficiently with CH₃B₁₂ or OHB₁₂. Holo-methionine synthetase was purified 244 fold with 56.4% recovery from Chromatium D cells grown with vitamin B₁₂ added. The partially purified enzyme required reductants but was only partially dependent on S-adenosyl-methionine.
On the other hand, Rsp. rubrum methionine synthetase which was always present as holoenzyme, in contrast with that of Chromatium D, was purified 40 fold with 2.8% recovery. The obtained preparation required S-adenosylmethionine and reductants for the enzyme activity. The optimal pH of Chromatium D enzyme and of Rsp. rubrum enzyme was in the range of 7.5_??_7.8 and 6.5_??_6.75, respectively.

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The contents of glycogen, lipid, urea and amino acids, and some enzyme activities in plasma, liver muscle and urine were determined with rats fed 10 to 12g of 100g body weight per day of the 10% casein diet (control) and 10% casein diets containing 7%. glycine with or without 1.4% L-arginine • HCl and L-methionine for 7 days.
Nine hours after the final feeding, the amount of liver glycogen was high in the order of rats fed 10% casein diet containing 7% glycine, 10% casein diet containing 7% glycine with L-arginine and L-methionine, and the control. The amount of muscle glycogen was decreased only in those fed the control diet. The amount of liver lipid was increased by the addition of L-arginine and L-methionine to the excess glycine diet. Plasma and urinary urea was increased in animals given the excess glycine diets with or without both amino acids. In plasma liver, and muscle of animals given either of both the excess glycine diets 3 and 9 hr after the feeding, in general, glycine and serine were increased, and threonine and alanine were de creased as compared with those of rats given the control diet. However, the increase of glycine in plasma, liver and muscle detected at 9 hr after feeding the excess glycine diet was slightly prevented by the supplementation of both amino acids to the excess glycine diet. The activities of liver glycine oxidase and ornithine δ-aminotransferase of rats given the excess glycine diet with both amino acids were higher than those of other dietary groups. Liver serine dehydratase and glutamate-oxalacetate transaminase activities were high in the order of the animals fed the control, the excess glycine diet and the excess glycine diet containing both amino acids. Glutamate-pyruvate transaminase activity in the liver of rats fed the excess glycine diets with or without both amino acids were markedly higher than that of those fed the control. The activities of phosphopyruvate carboxylase and aconitase in the liver of animals given the excess glycine diet were higher than those of other dietary groups. Liver pyruvate kinase and glutamate dehydrogenase activities were similar among those dietary groups.

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Optimal culture conditions for microbial production of tryptophan synthetase were studied. It was found that on cultivation of Escherichia coli 476, a tryptophan auxotroph, in a medium containing 5g/liter glycerol as C source, supplemented with 1g/liter of acid treated peptone, cells with high tryptophan synthetase activity could be obtained.
The enzyme was extracted from cells and 3-fold purified by heat treatment and ammo nium sulfate precipitation. The overall yield of the isolation procedure was 60%.
The partially purified tryptophan synthetase was entrapped in cellulose triacetate fibres. Under storage conditions, in refrigerator, the entrapped enzyme was stable at least for 6 months. The activity of the entrapped enzyme was about 75% with respect to the free enzyme.
Similar behaviour for the free and entrapped enzyme was observed as to the effect of temperature and pH on the enzymic activity. The operational stability of the entrapped tryptophan synthetase was very good (activity unchanged after 50 days) provided the accumulation of indole on the fibres was avoided.

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The synthesis of L-tryptophan from indole and DL-serine catalyzed by tryptophan synthetase entrapped in cellulose triacetate fibres was investigated using batch and continuous feed recycle reactors.
Tryptophan productivity, expressed as mg of tryptophan per hour per g of fibres, was 34 and 4 for the batch and the continuous reactor respectively; the final conversion of L-serine was 57% and 6.6%; practically all the indole was converted to tryptophan in the two reactors. Pyridoxal-5'-phosphate was necessary for the activity of the entrapped enzyme. D-Serine showed a slight inhibitory effect, was not utilized by the entrapped enzyme and after racemization at 160°C was reused. By increasing the molarity of the buffer used in the reaction mixture a decrease of tryptophan productivity was observed. The product, isolated from the reaction mixture was pure L-tryptophan.

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A new synthesis of α-damascone (a black tea aroma constituent having a powerful fragrance) was described.

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Several kinds of compounds were formed by Fusarium merismoides Bll when the fungus was grown in the medium containing 2-butyne-l, 4-diol as the sole source of carbon. Four of these compounds were isolated by thin-layer chromatography and identified as acetylene dicarboxylic acid, an ester of acetylene dicarboxylic acid with 2-butyne-1, 4-diol, an acetylated derivative of the ester, and cis-aconitic acid.

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When N-(3', 5'-dichlorophenyl)succinimide (DSI)-carbonyl-¹⁴C and -phenyl-³H were each orally administered to rats, regardless of the label site, most of the dose was readily eliminated. There was no difference in the excretion rate between male and female rats. No radioactive residues were detected in tissues and organs 24 hr after dosing. Urinary metabolites consisted of N-(3', 5'-dichlorophenyl) succinamic acid (DSA), N-(3', 5'-dichlorophenyl) malonamic acid (DMA), N-(3', 5'-dichlorophenyl)-2-hydroxysuccinamic acid (2-OH-DSA) and 2-OH-DSA derivatives. In dogs, most of the administered dose was excreted in equal amounts in urine and feces. 2-OH-DSA derivatives were main urinary metabolites and most of fecal radiocarbon was due to intact DSI. The results of this study indicate that DSI is a biodegradable compound which is unlikely to leave any persistent residues in animals.
The degradation of DSI to DSA was mediated by an arylamidase-type hydrolase, which was present in the microsomal fraction of rabbit liver. The enzyme activity was found in livers and kidneys of four animal species tested. Depending on the animal species, the enzyme appears to be important for the metabolism of DSI.

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The molecular species of glycerides and phospholipids of the yeast Lipomyces starkeyi IFO 0678 harvested at 60 hr, corresponding to the late exponential phase, were analyzed by gas chromatography-mass spectrometry. The major triglyceride was C_16:0-C_18:1-C_18:1. The major molecular species of phospholipid were 1-C_16:0-2-C_18:1 and 1-C_18:1-2-C_18:2. Although phosphatidylcholine and phosphatidylethanolamine were composed of several kinds of molecular species, 1-C_16:1-2-C_18:1, 1-C_18:1-2-C_18:2 and 1-C_16:0-2-C_18:1, phosphatidylserine was composed of almost exclusively 1-C_16:0-2-C_18:1. The lipid and the fatty acid compositions of the yeast harvested at the different growth phases were also investigated.

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5-Ketogluconate reductase (5 KGR) from the cell free extract of Gluconobacter liquefaciens (IFO 12388) was partially purified about 120-fold by a procedure employing ammonium sulfate fractionation, and DEAE-cellulose-, hydroxylapatite- and DEAE-Sephadex A-50-column chromatographies. NADP was specifically required for the oxidative reaction of gluconic acid. The optimum pH for the oxidation of gluconic acid (GA) to 5-ketogluconic acid (5 KGA) by the enzyme was 10.0 and for the reduction of 5 KGA was 7.5. The optimum temperature of the enzyme was 50°C for both reactions of oxidation and reduction. The enzyme was considerably unstable and lost all of its activity within 3 days. The enzyme activity was strongly inhibited with p-chloromercuribenzoate and mercury ion, but remarkably stimulated by EDTA (1×10^-3M). Apparent Km values were 1.8×10^-2M for GA, 0.9×10^-3M for 5 KGA, 1.6×10^-5M for NADP, and 1.1×10^-5M for NADPH².

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Thirty eight new compounds with juvenile hormone (JH) activity were synthesized and evaluated biologically on Bombyx mori L. Among them, the activities of 7, 8-epoxy-4, 8-dimethyl-1-(p-ethylphenoxy)-3-undecene and 7, 8-epoxy-4, 8-dimethyl-1-(p-methylphenoxy)-3-undencene were proved to be more than two thousand times as high as that of the C₁₈-Cecropia JH (mixed isomers). Structure-activity relationship of these compounds was discussed.

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Cerebroside was isolated from pea (Pisum sativum L.) seeds by solvent extraction, mild alkaline hydrolysis and silicic acid column chromatography. The purified material was identified as cerebroside by thin-layer chromatography and infrared spectrometry. Hydrolysates of the cerebroside were divided into fatty acid, sphingosine base and sugar fractions, and analysed, mainly by gas-liquid chromatography. The major fatty acid components were hydroxytricosanoic, hydroxydocosanoic and hydroxytetracosanoic acids. Dihydrosphingosine was the predominant sphingosine base. Only glucose was detected in the sugar fraction. Based on these results, one of the major species of pea cerebroside is suggested to be N-hydroxytricosanoyl-glucopyranosyl-dihydrosphingosine.

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A new synthetic method of cyclotene (3-methyl-2-cyclopenten-2-ol-1-one) (I) and its derivatives has been investigated. The reaction of 2-cyclopenten-2-ol-1-one and aniline in toluene gave the corresponding ketimine derivative (V) in good yield. The methylation of (V) afforded (I) and 5, 5-dimethyl-2-cyclopenten-2-ol-1-one (II) as the major reaction products, and 3, 5-dimethyl-2-cyclopenten-2-ol-1-one (III) and 3, 5, 5-trimethyl-2-cyclopenten-2-ol-1-one (IV) as the minor products. Similarly, ketimine derivative of (I) was alkylated with methyl iodide and ethyl iodide to yield the corresponding (II), (III), and 5-methyl-5-ethyl-2-cyclopenten-2-ol-1-one (VII), 3-methyl-5-ethyl-2-cyclopenten-2-ol-1-one (VIII), respectively, as the major products.

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Twenty one esters of trans β-(2, 4-dichlorophenoxy) acrylic acid were prepared and their inhibitory activity against shoot elongation in the rice plant and barnyard-grass was measured. The relationship between herbicidal activity and chemical structure was analysed using the Hansch approach. The selectivity (activity against barnyard-grass/activity against the rice plant) was mainly due to the lipophilic property of the esters between the two plant species.

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