An acidic xylan from the midrib of Nicotiana tabacum was isolated by alkaline extraction and fractionation on a DEAE-cellulose column. Based on the results of methylation analysis, partial acid hydrolysis and Smith degradation, the acidic xylan was concluded to be composed of a linear backbone of β-(1→4)-linked D-xylopyranosyl residues with approximately every ninth residue carrying a terminal 4-O-methyl-α-D-glucopyranosyluronic acid residue linked as a single side chain by (1→2) linkage.

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The p-menthane-utilizing microorganism, strain-SF, was identified to be a strain belonging to Pseudomonas mendocina by the physiological and morphological properties. The productivity of cis-p-menthan-1-ol by this strain was examined under various conditions, and as a result it was found that this strain required both magnesium and ferric ions for the hydroxylation of p-menthane, and that the productivity increased up 20% to 35 or 40% by adding 0.1% (w/v) of agar or a proper emulsifier (PEG nonylphenylether p:10) into the medium. On the other hand, some new metabolites which were assumed to be the intermediates were identified to be 1-hydroxymethyl-4-isopropyl cyclohexanol, 1-carboxy-4-isopropyl cyclohexanol, and 3-isopropyl heptanedioic acid by IR, PMR, MS and elementary analyse. From these results, the methabolic pathway of p-menthane by strain-SF was proposed.

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“Protein-like activator (PA)” for n-alkane oxidation was formed by Pseudomonas aeruginosa S₇B₁ from long-chain n-alkanes, 1-hexadecene and cetyl alcohol but not from glucose, glycerol and palmitic acid. The molecular weight and the total amino acid residues of PA were estimated at about 14, 300 and 147, respectively. PA was relatively stable to low pH and high temperature, and completely inactivated upon heating at 98°C for 45min. The cultural fluid obtained from n-hexadecane medium stimulated the growth of the strain on n-hexadecane. The degree of the growth stimulation by the fluid depended on the amount of PA and rhamnolipid (RL) in the fluid. The heat-treated PA lost the growth-stimulaing effect and the emulsifying power on the n-hexadecane medium in the presence of RL.

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The respiratory activity of Thiobacillus thiooxidans, even when the microorganism was incubated at pH 2.0, was not changed. In the presence of 0.1mM 2, 4-dinitrophenol (DNP), pentachlorophenol (PCP), tetraphenyl borate (TPB) and tributylamine (TBA), the respiratory activity was inhibited in acidic environments by DNP, PCP and TPB, while TBA inhibited the activity at neutral pH values. The inhibition degree by the uncouplers seemed parallel to their amount in undissociated form. The cells, when incubated at pH 2.0 or 4.0 in the presence of 0.1mM DNP, rapid or slow H⁺ influx into cells was observed, respectively. The uncouplers in undissociated form may have penetrated into the membrane and caused a conformational change of the membrane, which resulted in an inactivation of the respiratory system and in an H⁺ influx into cells.

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α-Mannosidase [EC 3. 2. 1. 24, α-D-mannoside mannohydrolase] from the acetone powder of pineapple fruit juice was purified 190-fold by column chromatographic procedures. The partially purified α-mannosidase was detected to be contaminated with little other glycosidases, using p-nitrophenyl derivatives of glycosides. The enzyme released mannose from both the carbohydrate moiety of stem bromelain and glycopeptide prepared from the parent protein. The enzyme split about 70% of the total mannose of ovalbumin glycopeptide.

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Several Cd²⁺ hypersensitive and Hg²⁺ sensitive mutants of Escherichia coli K-12 were isolated after repeated mutagenesis with nitrosoguanidine. The Cd-hypersensitive mutant, CD17P, could not grow in a chemically defined liquid medium containing 0.5 μM Cd²⁺, and the growth of Hg-sensitive mutant, HG17P-52, was inhibited by 0.9 μM Hg²⁺. Thus, CD17P and HG17P-52 were respectively about 1000 fold and 4 fold more sensitive than the parental strain.
Both mutants were also considerably more sensitive to Zn²⁺ than their parent, but they did not show any appreciable change in sensitivity to other metals tested. Among the various metabolites and chemicals tested, reducing agents such as cysteine, dithiothreitol and vitamin C showed a protective effect against metal toxicity. Reduced glutathione was effective only against Hg²⁺. EDTA specifically and efficiently reversed only Cd²⁺ toxicity.

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A simple method for purification and crystallization of primary alcohol dehydrogenase (EC 1. 1. 99. 8) is reported. The purification procedures consisted of four steps: protamine sulfate treatment, ammonium sulfate fractionation, passage through a column of DEAE-cellulose at pH 8.0 and Sephadex G-200 gel filtration. Crystallization was performed by the addition of ammonium sulfate at 65% saturation with an overall yield of 39%. The crystalline enzyme had an isoelectric point of pH 7.38 and a sedimentation coefficient (s⁰_{20, W}) of 8.44 s. A molecular weight of 128, 000 was estimated, and the enzyme consisted of two subunits each having a molecular weight of 62, 000. The enzyme showed an affinity toward the lower primary alcohols, methanol to n-pentanol. Formaldehyde was also oxidized by the crystalline enzyme. The Km values for methanol and formaldehyde were found to be 20 μM and 70 μM, respectively. Ammonium ions were required for enzyme activity.

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1. By spraying urea solution on leaves at the heading stage, high protein rice of 11% protein content was obtained without any loss in total amount of harvest. The protein quality of high protein rice was evaluated and compared with that of regular rice obtained without spraying urea solution.
2. Assessment of amino acid contents in brown and polished rices and brans showed that the high protein rice contained approximately 44% more protein in its endosperm than the regular rice. Stepwise extraction of rice proteins with different solvents showed that 70% of the extra protein in the high protein rice was glutelin. Amino acid scores of the high protein and regular rites were not significantly different. Although there was no difference in electrophoretic pattern between the proteins of the two ricer, the high protein rice showed more intense bands.
3. Endosperm protein of rice is composed of two major subunits of approximately 32, 000 and 21, 000 in molecular weight.
4. There was no difference between the high protein and regular rices in biological value, net protein ratio or net protein utilization.
5. These results reveal that the high protein rice discussed in the present paper contains in its endosperm more protein of an equivalent quality than the regular rice.

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Bovine κ-casein showed a typical CD spectrum for an aperiodic conformation in the far UV region. The comparison of the near UV absorption spectrum of native κ-casein with that of a model compound mixture (Ac-tyr-OEt+Ac-trp-OEt, molar ratio=9:1) showed a red shift of the former by 2nm to the longer wavelength. The difference spectra produced by the addition of urea to κ-casein solution showed three peaks at 280, 287, and 292 nm, of which the sign was negative (denaturation blue shift). The magnitude of the blue shift of the tryptophyl group was found to be -2, 200. It is concluded from these results that some tyrosyl groups are exposed to the solvent, and the other tyrosyl groups and a tryptophyl group are buried in the hydrophobic regions which is very susceptible to the action of a denaturing agent, urea. All the chromophores in κ-casein was exposed to the solvent in the presence of 4M urea. κ-Casein in the native state was proved to have an aperiodic structure but not a flexible random coil.

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An exo β-1, 3-glucanase has been purified from the culture fluid of a Fungi Imperfecti which had been used for the production of a yeast cell lytic enzyme, Method for the purification of the enzyme involved ammonium sulfate fractionation, column chromatography on DEAE-Sephadex A-50, BioGel P-150 and SE-Sephadex C-50, and affinity chromatography using powdered pachyman prepared from a Chinese medicine “Bukuryo, ” Poria cocos Wolf.
The molecular weight of the enzyme was determined to be 43, 000 by the molecular sieve method using BioGel P-60. The enzyme removes single glucosyl residues successively from the non reducing terminus of β-1, 3-glucan with inversion of configuration. The enzyme has comparatively narrow pH optima with an optimum pH of 6.0 and is most active at 50°C. The Km values of the enzyme for laminarin, laminarihexaose, laminaripentaose, and laminaritetraose are 0.066, 0.83, 2.30, and 18.60 (×10^-3M), respectively. Some other properties of the enzyme are also described.

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The synthesis of isocitrate lyase in Candida tropicalis, the growth of which was stimulated by exogenously added biotin, was released from repression by glucose under biotin-deficient conditions. Biotin deficiency reduced remarkably the levels of biotin-enzymes, pyruvate carboxylase and acetyl-CoA carboxylase, in the glucose-utilizing cells of this yeast. A marked increase in intracellular level of pyruvate was observed in the biotin-deficient cells. Acetyl-CoA-donating compounds, such as pyruvate, acetate and alkanes, stimulated the formation of isocitrate lyase in the yeast regardless of the presence or absence of biotin. On the other hand, malate and succinate did not affect the enzyme synthesis. The isocitrate lyase synthesis under biotin-sufficient conditions was repressed by not only glucose but also glucosamine and 2-deoxyglucose. This repression by glucose was not eliminated by cAMP. The stimulated synthesis of isocitrate lyase under biotin-deficient conditions was also observed in C. albicans and C. guilliermondii growing on glucose.

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NAD- and NADP-linked isocitrate dehydrogenases were purified 280-fold and 54-fold, respectively, from the cell-free extract of n-alkane-grown Candida tropicalis by means of ammonium sulfate fractionation, and column chromatography on Sephadex G-200 and DEAE-cellulose. NAD-linked isocitrate dehydrogenase was activated by AMP, ADP or citrate, whereas the NADP-linked enzyme was not affected by these compounds. The NAD-linked enzyme showed the kinetics of Michaelis-Menten type at a low concentration of MgCl₂ (3.3mM), while allosteric nature of the enzyme was observed at a high MgCl₂ concentration (33.3mM). Concomitant presence of glyoxylate and oxalacetate inhibited the reactions of both dehydrogenases. Especially, the NADP-linked enzyme was completely inhibited by these acids at a concentration of as low as 1mM each, showing a mixed pattern of inhibition.

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Contents and components of lipids in n-alkane-grown and glucose-grown cells of Candida tropicalis and Candida lipolytica were examined. Total lipid content of C. tropicalis cells grown on n-alkanes was 12_??_17% of dry cell weight, which was about twice as much as that of glucose-grown cells. This increment was due to an increase in the phospholipid content. The chain-length of n-alkane substrate did not have an appreciable influence on the lipid content of C. tropicalis, although it gave a significant effect on the composition of the cellular fatty acids. On the contrary, n-alkane-grown cells of C. lipolytica contained almost the same amount of total lipid as that of glucose-grown cells (about 4% of dry cell weight). C. tropicalis and C. lipolytica grown on n-alkanes and glucose showed similar profiles of lipid components, which were tentatively indentified. The neutral lipids were composed of triglyceride, free fatty acid, sterol ester, and some minor ingredients. Triglyceride was the major component of the neutral lipids. The major components of the phospholipids were phosphatidylethanolamine and phosphatidylcholine, and phosphatidylinositol and diphosphatidylglycerol (cardiolipin) were the minor components.

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Improvement of the initial stage of the autotrophic growth of hydrogen bacteria, strain 9-5 in sparged cultures was performed by employing air instead of pure oxygen as oxygen source. Elongation of exponential growth phase was also achieved with the aid of the determination of dissolved concentrations of hydrogen and oxygen. Under the gas composition, H₂:O₂:CO₂=67:23:10, dissolved concentrations of both hydrogen and oxygen were reduced to zero at the end of the exponential growth phase in sparged cultures. In addition, theoretical considerations for obtaining the optimal ratio of hydrogen and oxygen for the maximum critical cell concentration were performed.

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Formation and properties of diacetyl reductase were studied. Gluconate, acetate, pyruvate lactate, citrate and succinate increased the enzyme formation. The initial pH of the medium favorable for the enzyme formation was 7.0_??_8.0.
The enzyme was partially purified about 65-fold. The optimum pH value for the activity was 7.5 and the optimum temperature was 37°C. The enzyme was stable in the pH range of 7.0 to 8.0 and at the temperatures of 37°C and below. No metal ion which enhanced the enzyme activity was observed. Tris-HCl buffer reduced the enzyme activity.

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The structure of an arabinogalactan, separated from extracellular polysaccharides of cultured tobacco cells, has been investigated by methylation analysis of the original polysaccharide and of the products obtained after mild acid hydrolysis and after controlled Smith degradation.
The arabinogalactan consists of L-arabinose, D-galactose and L-rhamnose in the molar ratio of 47:45:8. The arabinogalactan has a main chain of (1→3)-linked D-galactopyranosyl residues, half of which are substituted at the 6-position. Most of the side chains consist of three (1→6)-linked D-galactopyranosyl residues, to which L-arabinose residues are attached at C-3. The L-arabinofuranosyl and pyranosyl residues are present as end groups, and L-arabinopyranosyl residues are attached to C-5 of L-arabinofuranosyl residues. Non-reducing terminal L-rhamnopyranosyl residues are also present.

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Methylation analyses and partial acid hydrolysis have indicated the similarity of the interior chains of the glucuronomannan, obtained from extracellular polysaccharides of tobacco cells to those of plant gums such as leiocarpan A and ghatti which contain contiguous 2-O-linked D-mannopyranose and 4-O-linked D-glucopyranosyluronic acid residues. Evidence also suggests that about 56% of 2-linked D-mannopyranose residues are substituted at position-3 with L-arabinofuranose residues as a single side chain.

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Eleven fluorine containing condensed thiazoles have been synthesized and characterized by spectral (IR and NMR) studies. Fungicidal activity of some representative compounds has also been evaluated.

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Alkali protease partially purified from a strain of Bacillus subtilis and yeast alcohol dehydrogenase were immobilized to weakly basic anion exchange resins using a bifunctional reagent, 2-carboxymethylamino-4, 6-dichloro-s-triazine.
Properties of these immobilized enzymes were studied both in batchwise operation and in packed bed reactor systems.

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Both neutral lactase partially purified from yeast and acid lactase prepared from fungi were immobilized to weakly basic anion exchange resin (Duolite A 7) chemically modified by a bifunctional reagent, 2-carboxymethylamino-4, 6-dichloro-s-triazine.
These immobilized enzymes could carry out a continuous hydrolysis of lactose in milk and whey, respectively, at appreciably high flow rates. The immobilized enzymes obtained were stable over broad ranges of pH and temperature and were protected from the attack by protease and bacteria.

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Strong kininase activity was found in various kinds of bean seed. The extract from 1g of varieties of beans inactivated 50_??_410 nmoles bradykinin when incubated for 1min at pH 7.4 and 30°C. A protease with kininase activity was partially purified from red kidney beans (Phaseolus vulgaris). The molecular weight of the bean protease was 73, 000, and its isoelectric point was 4.6. The enzyme appeared to be a metalloenzyme with a specificity similar to that of leucine aminopeptidase. The properties of the bean enzyme are similar to those of a bradykinin inactivating enzyme from potatoes (Solanum tuberosum).

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The efficiency of transfection of Escherichia coli spheroplasts increased when polyethylene glycol was used as an osmotic stabilizer instead of sucrose. Optimal concentration of polyethylene glycol was 0.5 to 1.0% for transfection with bacteriophage øX174 single-stranded DNA and 1.0 to 2.0% for that with øX174 double-stranded replicative form of DNA, and the efficiency of transfection increased 4 to 7-fold under these conditions. The extent of transfection of the spheroplasts prepared in the presence of polyethylene glycol was proportional to the number of phage DNA added. The effect of polyethylene glycol on transfection was independent of the presence of protamine sulfate.

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The structure of plumbemycin A and B, new antimetabolites from Streptomyces plumbeus, which are antagonist of L-threonine, were assigned to be L-alanyl-L-aspartyl-D-2-amino-5-phosphono-3-cis-pentenoic acid and L-alanyl-L-asparaginyl-D-2-amino-5-phosphono-3-cis-pentenoic acid, respectively.

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Gas-liquid chromatographic (GLC) methods were developed for the determination of 3-phenoxybenzyl dl-cis, traps-3-(2, 2-dichlorovinyl)-2, 2-dimethylcyclopropane-1-carboxylate (S-3151, permethrin or Exmin ^®), its geometrical and optical isomers and its impurities. dl-Trans and dl-cis isomers were separated from each other on a 2% LAC-2 R-446 column and determined by using dioctyl phthalate as an internal standard, and the overall content of S-3151 was obtained by the sum of them. Optical isomers, namely, d-cis, l-cis, d-trans and l-trans forms were hydrolysed to the corresponding acids, which were derivatized to the diastereoisomer esters with d- or l-2-octanol and separated from one another on a 10% silicone DC QF-1 column. The optical isomer ratios were determined by the peak area ratios. The impurities of S-3151 were identified by mass spectrometer combined with GLC on a 2% PEG-20M column and they were determined by programmed temperature GLC.

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The structure of piericidin A (Ia) was reexamined by means of the CMR spectroscopy and the ¹³C feeding studies and the structure la was revised to IIa. This structure was further confirmed by the selective reduction of PA and by the mass spectral analysis.

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Tsen's modification of Emmerie-Engel method was further improved by applying 3-(2-pyridyl)-5, 6-diphenyl-1, 2, 4-triazine (PDT) in place of bathophenanthroline as iron reagent. The reaction mixture of PDT, ferric chloride and tocopherol gave a spectrum with the maximum absorption at 554 nm. The sensitivity of PDT was about 1.2-fold of bathophenanthroline for each tocopherol. The rate of color development of PDT was fast similarly to bathophenanthroline. The calibration curves obtained for α-, β-, γ- and δ-tocopherols by the method using PDT followed Beer's law. The present method was much more economical than the bathophenanthroline method.

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