The enzymatic properties of two Avicelases, FI-Avicelase and FIII-Avicelase, from Aspergillus aculeatus No. F-50 were investigated. FI-Avicelase had an optimum pH of 5.5, but FIII-Avicelase had a low optimum pH of 2.5. The optimum temperature of both enzymes was 65°C. Both Avicelases were more active on amorphous cellulose, alkali and phosphate-swollen cellulose, and insoluble cellooligosaccharide, but their activities toward CM-cellulose and Avicel were very low. However, both Avicelases degraded Avicel to extents of 31-47%. Among the nine cellulase components of A. aculeatus No. F-50, the two Avicelases were essential enzymes for the degradation of crystalline cellulose.

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Convenient synthetic routes to 4R- and 4S-γ-lactones from respective D- and L-arabinoses are developed. An application of the routes to the chiral synthesis of a sex pheromone of Japanese beetle is presented.

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The importance of sialic acid to the foaming and emulsifying properties of ovomucin was investigated using asialoovomucin prepared by a neuraminidase treatment, which selectively cleaved the terminal sialic acid. The intrinsic viscosity of soluble ovomucin was decreased by the neuraminidase treatment, while that of reduced ovomucin was not similarly affected, suggesting the involvement of sialic acid in intermolecular interaction only for the regular conformation of ovomucin. The emulsifying properties of ovomucin were markedly decreased by the neuraminidase treatment, suggesting the importance of the repulsive force of sialic acid polyanions in the emulsion. On the other hand, the foaming properties of ovomucin were increased by the neuraminidase treatment. These results suggest that the electrostatic repulsive force of terminal sialic acids affects the emulsifying and foaming properties of ovomucin.

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A thermophilic fungus, strain A-131, isolated from a soil sample produced cellulases in the culture fluid. The fungus (strain A-131) was identified as Thermoascus aurantiacus Miehe from its taxonomical characteristics. The cellulases of T. aurantiacus A-131 were produced constitutively without cellulase inducers. Moreover, their production was induced markedly by amorphous polysaccharides containing β-1, 4 linkages such as alkali-treated bagasse and xylan rather than crystalline cellulose. The cultivation of T. aurantiacus A-131 at 45°C with 4% alkali-treated bagasse led to the production of about 70U/ml of CMCase after 4 days. The thermostability of the cellulolytic enzymes'of T. aurantiacus A-131 was excellent and virtually no decreases in their activities were seen after preincubation at 60°C for 24 hr.

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β-(1→4)-D-glucanase (I) was isolated and purified to homogeneity by SDS-gel electrophoresis from brewing malt. The enzyme had an endo-hydrolase action pattern against β-glucan and carboxymethyl cellulose, while it formed precipitates having mainly linear β-(1→4) linkages in the reaction against β-glucan. The enzyme catalyzed the reaction transferring the non-reducing end cellobiose or cellotriose moiety of cellopentaose to the non-reducing end glucosyl residue of cellopentaose, and the resulting reducing end cellotriose, cellobiose, and precipitates were detected in the reaction mixture. The precipitates were found to be a linear β-(1→4) linked glucan having an average degree of polymerization of 10. These results indicated that β-(1→4)-D-glucanase (I) had a strict specificity of forming β-(1→4) linkages and had a capacity to elongate the linkage to a higher extent.

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The mechanism of induction of glycolate excretion by aminooxyacetate (AOA) during photosynthesis in Euglena gracilis Z has been studied enzymologically and metabolically. AOA inhibited glutamate: glyoxylate aminotransferase competitively with glutamate with Ki's. of 0.7 and 9.5 μM. Glycolate dehydrogenase and NADPH: glyoxylate reductase were also competitively inhibited by AOA with glycolate and glyoxylate, respectively. The Ki's were 1.2 and 0.4 mM, respectively. These inhibitions of the glycolate pathway enzymes could not be the immediate cause of the induction of the excretion. Intracellular concentrations of glycolate and glyoxylate were 10 and 3 nmol/mg chlorophyll in photosynthesizing Euglena. Addition of AOA to the cells caused increases of both metabolites to 13 and 7 nmol/mg chlorophyll, respectively. Glycolate dehydrogenase was strongly inhibited by glyoxylate competitively with glycolate. The Ki was 10 μM, less than one-fifteenth of the Km of glycolate dehydrogenase for glycolate. These results suggest that inhibition of glutamate: glyoxylate aminotransferase increases the glyoxylate concentration which inhibits glycolate oxidation and such a disturbance of an intracellular equilibrium of glycolate and glyoxylate levels makes a glycolate-excreting transporter operate.

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To investigate the effects of dietary glucose and fructose on serum lipids, rats of four strains (Donryu, Sprague-Dawley, Fischer and Wistar) were fed a diet containing either glucose or fructose. Fructose feeding to all rats weighing about 140g of the four strains resulted in significant increases in serum cholesterol and triglyceride.
Of the Donryu rats with initial body weights of 65 g, 179g and 463 g, serum cholesterol increased in those weighing 179g when fed a fructose diet. Whereas, fructose feeding resulted in significant increases in serum triglyceride in those weighing about 179 g and 463 g. Therefore, in the following experiments, rats of the Donryu strain weighing about 120 - 160 g were used.
The hypercholesterolemia induced on feeding a fructose diet to the Donryu rats was prevented by the addition of corn oil, konjac mannan, pectin, guar gum, cholestyramine and clofibrate. Both cholestyramine and phthalate were effective, respectively, in preventing the increase in serum triglyceride.
Fructose caused a slight increase in or showed an increasing tendency as to the liver lipid content, and a slight reduction in or a decreasing tendency as to the liver cholesterol level as compared to in the case of glucose except for a few results. The addition of fibers and hypolipidemic drugs had no effects on the Hver lipids.
The overall results indicate that the effects of fibers and hypolipidemic drugs on serum cholesterol in rats fed a fructose diet are similar to those reported previously for rats fed either a cholesterol-diet or a histidine-excess diet.

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The present work was conducted to identify the carbonyl compounds responsible for the glucose-induced polymerization of proteins and the impairment of their amino acid residues.
Non-nitrogenous intermediate products of the Maillard reaction (IMR) were prepared through the reaction of glucose with butylamine, and the most major product was identified as 3-deoxyglucosone (3DG) by mass spectrometry and ¹³C NMR. Thus, 3DG was purified from IMR and stored with proteins.
3DG polymerized both lysozyme and acetylated lysozyme, and impaired Arg, Lys and Trp residues of lysozyme, and Arg and Trp residues of acetylated lysozyme, when incubated at 50°C and 75% relative humidity for 3 days. The elution pattern of the impaired Arg residues during an amino acid analysis was exactly the same as that- observed in the glucose-induced modification of lysozyme.
3DG induced the same alteration in ovalbumin, bovine serum albumin and insulin, as that in lysozyme.
All these results indicate that 3DG was the cross-linker responsible for the glucose-induced polymerization of proteins, and the attacker of their Arg, Lys and Trp residues.

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Methods for efficient extraction and simple purification of the lipopolysaccharide specific for Mycobacterium tuberculosis were developed. Crude lipopolysaccharide was obtained from sterilized cells through mechanical disintegration, Triton X-100 extraction, ethanol precipitation, glucosidase digestion, and gel-filtration chromatography. The lipopolysaccharide was further purified by treatments with pyridine-methanol and chloroform-methanol to remove the contaminating glycolipids and phospholipids, and by digestion with the immobilized trypsin to remove the contaminating proteins. The purified lipopolysaccharide was composed of a polysaccharide consisting of D-mannose and D-arabinose, and fatty acids, mainly palmitic, tuberculostearic, and stearic acids, which were bound in ester linkages. The lipopolysaccharide had strong tumor regressing activity on the mouse fibrosarcoma.

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Bifidobacterium breve 203, an isolate which assimilates β-D-glucosides weakly, came to grow well on cellobiose (B. breve clb strain) or gentiobiose (B. breve gnt strain) after successive transfers in medium containing cellobiose or gentiobiose as a carbon source. The elevation of the assimilating ability of B. breve clb, which might reflect both higher cellobiose consuming- and β-D-glucosidase I activities than those of the original B. breve 203, was specific to cellobiose. In the case of B. breve gnt, the elevated assimilating ability was specific to gentiobiose, with higher gentiobiose consumingand β-D-glucosidase II activities. Subsequent transfers (10 times) of B. breve clb in medium with glucose as a carbon source resulted only in a decrease in cellobiose consumption by the intact cells, while similar treatment of B. breve gnt resulted in decreases in both gentiobiose consumption and β-D-glucosidase II activity. β-D-Glucosidase I partially purified from B. breve clb grown on glucose as a carbon source showed the same properties as the enzyme from B. breve 203 in molecular weight, optimum pH for the reaction, effects of divalent cations and sulfhydryl reagents, substrate specificity, β-D-fucoside-transferring activity and so on.

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The coagulation of soybean protein by a CaCl₂ solution, involving the binding of calcium to the coagulate, was analyzed as the superposition of reversibly bound calcium to soybean protein and irreversibly bound calcium to phytate. The maximum moles of the two calcium binding sites and the binding constants were estimated and compared with the results in literature. The mixing conditions at the time of coagulation were important for controlling the calcium and phosphorus contents of the coagulate.

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The reaction conditions for the production of D-p-hydroxyphenylglycine (D-HPG) from DL-5-(p-hydroxyphenyl)hydantoin (DL-HPH) by cells of Pseudomonas sp. AJ-11220, and the cultural conditions for this bacterium for the formation of the D-HPG-producing enzyme involved by this bacterium were investigated. The optimal pH of this reaction was about 8.0 and the optimal temperature about 43°C. The D-HPG-producing enzyme was inducibly produced in Pseudomonas sp. AJ-11220 in proportion to the cell growth. Cells containing high activity were obtained when Pseudomonas sp. AJ-11220 was grown in a medium containing 20 g of glucose, 5 g of (NH₄)₂SO₄, 1g of KH₂P0₄, 3g of K₂HP0₄, 0.5g of MgSO₄•7H₂O, 0.01g of FeSO₄•7H₂O, 0.01g of MnSO₄•4H₂O, lOg of yeast extract, 5g of DL-5-cyanoethylhydantoin and 20g of CaCO₃ in a total volume of 1 liter (pH 7.0). Under the optimal conditions, 25mg/ml of D-HPG was asymmetrically and directly produced from 30 mg/ml of DL-HPH with a molar yield of 92%. Various D-amino acids could also be effectively produced from the corresponding 5-substituted hydantoins.

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The mechanism of asymmetric production of D-amino acids from the corresponding hydantoins by Pseudomonas sp. AJ-11220 was examined by investigating the properties of the enzymes involved in the hydrolysis of DL-5-substituted hydantoins. The enzymatic production of D-amino acids from the corresponding hydantoins by Pseudomonas sp. AJ-11220 involved the following two successive reactions; the D-isomer specific hydrolysis, i.e., the ring opening of D-5-substituted hydantoins to D-form N-carbamyl amino acids by an enzyme, D-hydantoin hydrolase (D-HYD hydrolase), followed by the D-isomer specific hydrolysis, i.e., the cleavage of N-carbamyl-D-amino acids to D-amino acids by an enzyme, N-carbamyl-D-amino acid hydrolase (o-NCA hydrolase).
L-5-Substituted hydantoins not hydrolyzed by D-HYD hydrolase were con verted" to D-form 5-substituted hydantoins through spontaneous racemization under the enzymatic reaction conditions.
It was proposed that almost all of the DL-5-substituted hydantoins were stoichiometrically and directly converted to the corresponding D-amino acids through the successive reactions of D-HYD hydrolase and o-NCA hydrolase in parrallel with the spontaneous racemization of L-5-substituted hydantoins to those of DL-form.

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The reaction conditions for the production of L-tryptophan from DL-5-indolylmethylhydantoin by Flavobacterium sp. AJ-3940, and the cultural conditions for the formation of the enzyme involved by this bacterium were investigated. The optimal pH of this reaction was around 8.5 and the optimal temperature was between 45 to 55°C. The amount of L-tryptophan produced was remarkably increased by the addition of inosine, which formed a water insoluble adduct with L-tryptophan, to the reaction mixture because of the release of end-product inhibition by L-tryptophan. This enzyme was inducibly and intracellularly produced by Flavobacterium sp. AJ-3940 in proportion to the increase in cell growth. Cells showing high activity were obtained using a medium containing 5g glucose, 5g (NH₄)₂SO₄, 1g KH₂PO₄, 3g K₂HPO₄, 0.1g MgSO₄•7H₂O, 0.01g CaCl₂•2H₂O, 50ml corn steep liquor and 3.5 g DL-5-indolylmethylhydantoin in a total volume of 1 liter (pH 7.0). Under the best conditions, 43 mg/ml of L-tryptophan was produced from 50 mg/ml of DL-5-indolylmethylhydantoin with a molar yield of 97% in the presence of cells of Flavobacterium sp. AJ-3940. In addition, other L-aromatic amino acids such as L-phenylalanine, L-tyrosine, L-DOPA and related L-amino acids were also produced from the corresponding 5-substituted hydantoins by this bacterium containing the L-tryptophan-producing enzyme induced by DL-5-indolylmethylhydantoin.

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The mechanism of asymmetric production of L-arorriatic amino acids from the corresponding hydantoins by Flavobacterium sp. AJ-3912 was examined by investigating the properties of the enzymes involved in the hydrolysis of 5-substituted hydantoins corresponding to aromatic amino acids (AAH). The enzymatic hydrolysis of AAH by Flavobacterium sp. AJ-3912 consisted of the following two successive reactions; a hydrolytic ring opening reaction of DL-AAH to L- and D-form N-carbamyl aromatic amino acids (NCA), involving an enzyme (hydantoin hydrolase), followed by a hydrolytic cleaving reaction of the L-form NCA to L-aromatic amino acids involving another enzyme (N-carbamyl-L-aromatic amino acid hydrolase, abbreviated as L-NCA hydrolase). The ring opening reaction involving hydantoin hydrolase was not stereospecific, but the NCA cleaving reaction involving L-NCA hydrolase was completely L-specific. The pathway for the conversion of the by-produced D-form NCA to L-aromatic amino acids was as follows; conversion of D-form NCA to D-A AH through the reverse reaction of hydantoin hydrolase, and then conversion of the D-AAH to L-AAH through spontaneous racemization, followed by the successive hydrolysis of the L-AAH to L-aromatic amino acids by hydantoin hydrolase and L-NCA hydrolase.

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D-Gluconate dehydrogenase (EC. 1.1.99.3) from Pseudomonas fluorescens was immobilized on the surface of a ubiquinone-mixed carbon paste electrode by irreversible adsorption. This electrode could oxidize D-gluconate electrocatalytically, with ubiquinone serving as an electron transfer mediator between the carbon paste electrode and the immobilized enzyme. The catalytic oxidation current observed with this electrode was analyzed as a function of the concentration of D-gluconate, the amount of mixed ubiquinone in the carbon paste electrode and the potential applied to the electrode. The results were explained by the theory of the catalytic current at an enzyme-modified electrode with an electron transfer mediator. The parameters characterizing the current response of the electrode to D-gluconate were determined.

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A particulate enzyme fraction capable of catalyzing the transfer of glucose from UDP-glucose to β-glucan was prepared from the mycelium and protoplasts of Pyricularia oryzae P₂. An assay method for the β-glucan synthase was developed. About 80% of the β-glucan synthase activity was found in the pellet obtained on centrifugation at 28, 000 × g for 30min. The particulate enzyme preparation showed β-glucan and glycogen synthase activities, in a ratio of 7:3. The optimum temperature and pH of the enzyme were found to be 20°C and 7.0, respectively. The glucan synthase activity increased 5.7-fold in 5hr after the onset of protoplast regeneration.

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Dynamic profiles of the rate of O₂^- generation from press-injured and inoculated rice leaf slices, versus the time after inoculation, discriminated between the incompatible and compatible combination of blast fungus races with a cultivar. The application of sodium saccharin to rice seedlings via the root system for 6 days changed the compatible to incompatible profile. Even after press-injury and inoculation with the compatible conidia, the leaf application of sodium saccharin enhanced superoxide generation. The application of N-methylsaccharin in a similar manner, however, did not enhance the superoxide generation. Inoculation of press-injured leaves with incompatible conidia in the presence of an aqueous diffusate of the germinating compatible conidia changed the incompatible to compatible profile. The application to press-injured of concanavalin A or a lyophylized preparation from 5M ammonia extracts of rice leaf homogenate prior to stimulating with a resistance-inducing factor (RIF) from the fungus also enhanced the superoxide generation. The RIF, either from the incompatible or compatible race, gave a quite similar profile of activation upon the generation of the superoxide anion.

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Heat-induced transparent gels from ovalbumin solution can be prepared, but only at low ionic strength, which limits their practical uses. We describe here their preparation at different salt concentrations. Ovalbumin solution (5% w/v) was heated at 80°C, pH 7.0, for 1 hr without salt to give a transparent solution. This solution was cooled and reheated with 0.2 M NaCl, which converted it to a transparent gel. At higher NaCl concentrations, the gel was harder and slightly turbid. We examined the change in the ovalbumin molecule when heated without salt. Gel filtration showed that with heating, the amount of ovalbumin monomers decreased and another peak appeared. After 30 min of heating, there was only one peak. This was a soluble aggregate. SDS-HPLC showed that this soluble aggregate was composed of monomers and oligomers connected by a disulfide bridge or bridges. A conformational change was detected with the difference spectrum. The number of sulfhydryl residues decreased slightly.

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A mechanistic investigation of the maceration of mitsumata (Edgeworthia papyrifera Sieb. et Zucc) bast by pectinolytic enzymes from Erwinia chrysanthemi GIR 2002 was performed. Of the two maceration factors, endo-pectate lyase and endo-pectin lyase (endo-PNTE), endo-PNTE showed only a slight maceration potential in spite of possessing high enzyme activity. The isoelectric point and affinity toward partially esterifled pectins of this enzyme were considerably lower than those of endo-PNTE from E. carotovora PERM P-7576. In the presence of Ca²⁺, an ion which is supposed to screen the negative charges on pectic substances, PNTE of strain GIR 2002 improved as to this affinity and the maceration potential, the same levels as those in the case of the enzyme from PERM P-7576 almost being attained. It was strongly suggested that the low maceration activity of the enzymes from GIR 2002 was due to the malfunctioning of endo-PNTE due to ionic repulsion between the negative charges on the enzyme molecule and those on pectic substances in the bast fibers.

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Various microorganisms were screened for high arachidonic acid productivity. An isolated fungus, strain 1S-5, identified as Mortierella elongata Linnemann, was found to show the highest productivity. Using this fungus, the cultural conditions for high intracellular production of arachidonic acid were investigated. The production of arachidonic acid reached 0.99mg/ml (22mg/g dry cells) when the fungus was grown in a medium containing 10% glucose, 0.5% Polypepton and 0.3% yeast extract, pH 6.0, for 4 days at 24°C with shaking. The arachidonic acid could be isolated as the methyl ester from mycelia with a good recovery.

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(±)-cis-γ-Irone (1a), (±)-cis-dihydro-γ-irone (2a) and their trans-isomers (1b, 2b) were synthesized via 3, 3-(Claisen) or 2, 3-sigmatropic rearrangement of 1-hydroxymethyl-3, 3, 4-trimethyl-1-cyclehexene (8) derivatives as each key step.

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Five hybridoma cell lines, 21B3, 31A4, 61C1, 61B4, and 62A6 were established and characterized to produce IgG₁ antibodies with specificity for bovine β-1actoglobulin (β-LG) which is a potent milk allergen. A representative monoclonal antibody (MAb) 21B3 had a unique affinity; it bound more strongly to RCM (reduced carboxymethylated) β-LG than to native β-LG. The affinity increased drastically when β-LG was heated at 70°C or above for 10min at pH 7.0, while β-LG heated at pH 3.0 did not alter its affinity even when heated at 80°C for 10min. An enzymeprobe method suggested that unfolding of β-LG by heating at pH 7.0 seemed to start at 70°C, and β-LG heated at 90°C and RCM β-LG were extensively unfolded. The results indicated that the phase of unfolding and increase of affinity by heating were coincidental. Finally the relationship of the unique affinity of MAb and the β-LG conformation was discussed.

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B-1625 FA_2β, one of the minor acidic actinomycin congeners produced by Streptomyces antibioticus No. B-1625, was produced selectively on the combined use of sarcosine and ferrous sulfate in a complex medium. The FA_2β was further separated into two components, MeOH-insoluble FA_2β-1 and MeOH-soluble FA_2β-2, by methanol treatment. After repeating the MeOH treatment, the purified FA_2β-1 was examined as to its physicochemical properties, and subjected to amino acid analysis, and ¹³C-, ¹H-NMR and FAB mass spectral measurements. As a result, the structure of FA_2β-1 was deduced to be 2-amino-1-carboxyl-4, 6-dimethyl-3-phenoxazone-9-carbonyl-threonyl-valyl-sarcosyl-sarcosyl-N-methylvaline. As much as 1mg/ml of FA_2β-1 showed no antibacterial activity against Gram-negative or Gram-positive bacteria, although FA_2β-2 shows antibiotic activity.

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After male rats of the Sprague Dawley strain, 5 weeks old, were fed a 20% casein diet with or without 0.5% nicotinamide for 13 days, 180mg/kg body weight of alloxan was injected intraperitoneally into the rats. The rats were kept for 18 days with the same diet. The level of blood glucose was increased 6-fold in the group on a 20% casein diet by the injection of alloxan, while there was only a 2-fold increase in the group on a nicotinamide-containing diet and the decreased body weight was also lower in the group on the nicotinamide diet than the group on the casein diet. The body weight was indirectly related to the concentration of blood glucose. A marked increase was observed in the activities of tryptophan oxygenase, aminocarboxymuconate-semialdehyde decarboxylase, and nicotinamide methyltransferase upon the injection of alloxan with both diets; on the other hand, the activities of kynureninase and NAD⁺ synthetase were decreased by the injection of alloxan. The activity of kynurenine aminotransferase increased in the group on the 20% casein diet by the injection of alloxan, while in the group on the nicotinamide-containing diet its activity was not increased by the injection. These changes in the above enzyme activities mean that the conversion ratio from tryptophan to niacin is lower in the alloxan diabetic rat than normal rat. It was found that the activities of tryptophan oxygenase, aminocarboxymuconate-semialdehyde decarboxylase, and nicotinamide methyltransferase were directly related to the concentration of blood glucose, and that the activities of kynureninase and NAD⁺ synthetase were inversely related. There was no difference in the activities of 3-hydroxyanthranilic acid oxygenase and nicotinamide mononucleotide adenylyltransferase upon the injection of alloxan with both diets.

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Artificial casein micelles were prepared at a casein concentration of 2.5% with various salt compositions, and the content of the casein aggregates cross-linked by colloidal calcium phosphate (CCP) was determined by high-performance gel chromatography on a TSK-GEL G4000SW column, using 6M urea-simulated milk ultrafiltrate as the effluent. When phosphate was incorporated into calcium caseinate micelle systems, the casein aggregates cross-linked by CCP appeared. In these micelle systems, not all of the formed calcium phosphate seemed to participate in cross-linking, because part of the calcium phosphate was in the urea-insoluble form. When micelles were prepared at 30mM calcium and 22mM phosphate, the content of the casein aggregates cross-linked by CCP was higher in the presence of 10mM citrate than in the absence of citrate. The precipitate of calcium phosphate formed in the presence of citrate had cross-linking ability, whereas the precipitate formed in the absence of citrate did not. It is suggested that citrate plays an important role in cross-linking by CCP. Magnesium phosphate alone had no cross-linking ability. Magnesium increased the amount of calcium phosphate to promote cross-linking.

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Five genes for tryptophan biosynthesis, trpE, trpD, trpC, trpB, and trpA of Brevibacterium lactofermentum, a coryne form glutamic acid-producing bacterium, were cloned as a 9.6 kb BamH1 DNA fragment by colony hybridization. A previously cloned 1.2 kb PstI DNA fragment containing a major part of the trpE gene was used as a probe. By complementation tests using the subclones of this 9.6kb BamHI fragment and various tryptophan auxotrophs of B. lactofermentum and Escherichia coli, this fragment was found to contain a gene cluster composed of trpE, trpD, trpC, trpB, and trpA in this order. It suggests that genes for tryptophan biosynthesis in B. lactofermentum may be an operon.

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A relaxed (rel) mutant was found among thirty spontaneous thiopeptin-resistant isolates of Streptomyces antibioticus strain 3720, an actinomycin-producing strain, which showed severely reduced ability to accumulate ppGpp during a nutritional shift-down. The pool size of GTP decreased markedly in the parental strain, but to a lesser extent in the rel mutant. The rel mutant did not show the induction of an enzyme, phenoxazinone synthase, which is involved in the biosynthesis of actinomycin. No negative effect of the rel mutation was observed on a constitutive enzyme, kynurenine formamidase, which also plays a role in actinomycin synthesis. The mutant also failed to produce melanin, but still retained the ability to form aerial mycelium and spores, although the onset of the formation of aerial mycelium was markedly delayed. Neither the phenoxazinone synthase activity nor the kynurenine formamidase activity was affected by ppGpp in vitro. It is suggested tha the stringent response (ppGpp) may be generally essential for the induction of enzymes involved in secondary metabolism.

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Previous studies of potato varieties indicated that changes during cooking could be mathematically described and that some chemical components and the cell size may influence the cooking behavior. To find out whether the same principles can be adopted for other root vegetables, the cooking behavior of three other low-starch root vegetables were investigated and the results compared. Slices (6mm thick and 30mm diameter) were treated in water at 10°C. Mathematical expressions were assessed, and coefficients were determined to describe the kinetic behavior of the products. The cell size and pectin content of the raw materials determined the cooking characteristics. Texture development could be predicted by shear force measurements.

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A human opioid peptide hormone, β-endorphin, was expressed in Escherichia coli as the C-terminal portion of a fused protein. The fused protein consisting of the N-terminal 62% of E. coli anthranilate synthetase (323 amino acids), a peptide corresponding to the linker DNA (7 amino acids), and the precursor form of β-endorphin (47 amino acids), was highly expressed under the control of a tryptophan promoter. The level of expression of β-endorphin was estimated to be 17mg/liter broth by radioimmunoassay, and 51 mg/liter broth by SDS polyacrylamide gel electrophoresis followed by a densitometric analysis, β-Endorphin was cleaved from the fused protein and purified by HPLC, and is presumed to be identical with human β-endorphin because of its amino acid composition and amino acid sequence.

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Rustmicin, a new antibiotic active against the wheat stem rust fungus, was isolated from a cultured broth of Micromonospora chalcea 980-MC₁. Rustmicin showed strong inhibitory activity against the wheat stem rust fungus both in vitro and in pot tests in a greenhouse with MIC being 1 and 0.8μg/ml, respectively. Its structure was determined by NMR spectroscopy to be a new 14-membered macrolide antibiotic lacking sugar substituents.

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A new type of cysteine proteinase inhibitors, staccopin P1 and P2, are low molecular weight (lower than 1, 000) peptide derivatives isolated first from Staphylococcus sp. Staccopins strongly inhibited only cysteine proteinases like calpain and papain, but were not active against serine proteinases like trypsin and chymotrypsin. The purification procedures included HP-20 adsorption chromatography, DEAE-cellulose, CM-cellulose, Sephadex LH-20 column chromatography, and high-performance liquid chromatography. The yields were 49 mg and 18mg from 20 liters each of culture fluid. These proteinase inhibitors are pentapeptides containing valine and phenylalaninal for staccopin P1 or tyrosinal for staccopin P2, and the N-terminals of both pep tides are free. Thus the structures are H-valyl-valyl-valyl-valyl-phenylalaninal for staccopin P1 and H-valyl-valyl-valylvalyl-tyrosinal for staccopin P2. The amino acid sequence-inhibitory activity relationships of Staccopins and other low molecular weight peptide cysteine proteinase inhibitors derived from natural sources are discussed.

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The activities of isocitrate lyase and malate synthase-the key enzymes in the glyoxylate cycle-were found to be fairly high in n-alkane-, acetate-, and propionate-grown cells of Candida tropicalis compared with those in glucose-grown cells. In fact, the results of immunochemical studies showed that the increases in the enzyme levels resulted from increases in the amounts of the enzyme proteins. But the increases in these enzyme activities were not always coincident with the appearance of peroxisomes. Isocitrate lyase and malate synthase were purified from a peroxisome-containing particulate fraction of alkane-grown cells and from whole cells grown on glucose, acetate and propionate. The respective enzymes showed no significant differences in immunochemical properties, specific activities, molecular masses of active forms and subunits, on patterns of limited proteolysis with proteases, but the malate synthases of alkane- and propionate-grown cells showed higher Km values for acetyl-CoA than the enzymes of glucose- and acetate-grown cells. The results indicated that the synthesis of the key enzymes in the glyoxylate cycle did not necessarily have to be coincident with the development of peroxisomes in this yeast.

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Two principal toxins of diarrhetic shellfish poisoning, okadaic acid and dinophysistoxin-1, were esterified with 9-anthryldiazomethane in methanol. After cleaning with a Sep-pak silica cartridge column, the fluorescent esters were analyzed on a Develosil ODS column with MeCN-MeOH-H₂O (8:1:1). The fluorescence intensities of both toxin derivatives measured at an excitation of 365 nm and an emission of 412 nm showed good linearity in the range 1-80ng.

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A new inhibitor of plant virus infection from fruiting bodies of Lentinus edodes was purified by a method using fractionation with DEAE-Cellulose, gel filtration on Sephadex G-75, and column chromatography on CM-Toyopearl 650M. The purified inhibitor thus obtained was homogeneous on disc and SDS disc electrophoreses, and the molecular weight of the inhibitor was 23, 000. The inhibitor consisted of 17.4% nitrogen, which was found to be a basic simple protein, but contained no neutral sugar, hexosamine nor sialic acid. The inhibitor was estimated to be composed of about 199 amino acid residues. This inhibitor was named "fruiting body protein (FBP)."

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An inhibitor of plant virus infection from leaves of Yucca recurvifolia was purified by a method using gel filtration on Sephadex G-75, and column chromatography on CM-Toyopearl 650M. The purified inhibitor thus obtained was homogeneous on disc and SDS disc electrophoreses, and the molecular weight of the inhibitor was 23, 000. The inhibitor consisted of 17.7% nitrogen, which was found to be a basic simple protein, and contained no neutral sugar, hexosamine nor sialic acid. The inhibitor was estimated to be composed of about 208 amino acid residues. This inhibitor was named "yucca leaf protein (YLP)."

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One of the inhibitors, named "fruiting body protein (FBP), " was purified from fruiting bodies of Lentinus edodes, and the other, named "yucca leaf protein (YLP), " from leaves of Yucca recurvifolia Salisb. The properties of these inhibitors were investigated, and the concentration of substances for a 50% inhibition ratio of TMV infection were measured. The inhibition ratios of YLP, FBP, Poly-Lys, Poly-Orn, Poly-Arg and cytochrome c were 0.6, 6.3, 14.1, 31.6, 44.7 and 100 ppm, respectively. Two inhibitors had no RNA hydrolyzing activity and no activity to TMV aggregation. FBP and YLP prevented infection of the plant by TMV when treated within 3 days before TMV inoculation, but not when treated within 1 hr for FBP or 3 hr for YLP after TMV inoculation. It seems that these two inhibitors had a preventive effect on plant virus infection, but no curative effect.

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Erythropoietin (Ep) was isolated from the urine of patients with aplastic anemia [Yanagawa et al, J. Biol. Chem., 259, 2707 (1984)] and burst-promoting activity (BPA) was extensively purified from the residue obtained after removal of Ep. These erythropoietic factors were studied for their effcects on erythroid burst-colony formation of human peripheral blood mononuclear cells in methylcellulose cultures. Reddish bursts were formed with the addition of Ep alone. Addition of BPA not only elevated the number of bursts but also greatly reduced the amount of Ep required for burst formation. The presence of BPA alone in cultures did not permit bursts to form but did permit the growth of small colonies that did not contain hemoglobin (Hb). Addition of Ep to these small colonies led to the formation of erythroid bursts. Administration of Ep to the cultures could be delayed for 6 days without decreasing the number of bursts if the cultures were initiated in the presence of BPA; in the absence of BPA, the erythroid precursors (BUF-E) were rapidly lost if Ep was not provided at the start of the cultures. BPA produced larger bursts than those formed in the presence of Ep alone. Microassays of Hb in the bursts indicated that BPA increased the amonut of Hb per burst. This increase could not be entirely explained by the augumentation in cell number per burst but was partly ascribable to the increased amount of Hb per cell.

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