When pressed baker's yeast (Saccharomyces cerevisiae) was exposed to the vapour of acetic acid, autolysis of yeast cells was induced in 3 or 4hr. In order to elucidate the mechanism of the autolysis caused by the AcOH-treatment, we investigated variations in the lipid content of yeast cells during the treatment. The degradation of phospholipids and the accumulation of free fatty acids occurred within 3hr. Formic acid exerted a similar effect on the pressed yeast. The effect of propionic acid was not seen in 3hr but was after 18hr. When the homogenate of fresh yeast cells was incubated in the acidic region below pH 4.5 for 1hr, phospholipids were hydrolyzed and free fatty acids were accumulated. Such deacylation of phospholipids was observed even at pH 6 on incubation for 12hr, but not observed at pH 7 or above pH 9. At pH 8, although phospholipids were somewhat degraded, free fatty acids almost never accumulated but diacylglycerol did accumulate.
Therefore, yeast cells have inherently phospholipid-acylhydrolases and, on AcOH-treatment, such enzymes may degrade membrane phospholipids to induce the autolysis of pressed yeast.

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The utilization of 28 nitrogen compounds and 24 carbohydrates by 23 strains of Micromonospora was examined after growth on a chemically defined medium. Inorganic ammonium salts served as better nitrogen sources than nitrate salts, and most of the organisms metabolized acidic or basic amino acids more extensively than neutral ones, except for L-serine. Utilization of carbohydrates in the defined medium did not always correspond to that observed when Luedemann's medium was used as a basal medium. Experiments using p-nitrophenylglycosides indicated that α-glucosidase, β-glucosidase, β-galactosidase and β-N-acetylglucosaminidase were present in all the strains. The diagnostic properties found in this study are discussed in terms of the classification of Micromonospora species.

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The phenyl group at C-7 of grossamide (1) was determined by PMR spectra to be situated in a trans relationship to the carbonyl group at C-8. It was elucidated that the hordatines (3a, 4a) also have a trans configuration.

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The reformation of casein micelles was investigated by dialysis of simulated milk ultrafiltrate or skimmilk at a fixed temperature or by increasing the temperature from 5°C to 37°C. When submicelles were dialyzed at a fixed temperature the micelles were not reformed, but were when the submicelles were dialyzed as the temperature was increased from 5°C to 37°C. The salt content, casein composition and size distribution of the reformed micelles were approximately 70% of original micelles when the submicelles were dialyzed against skimmilk. The submicelles obtained from large micelles reformed into large micelles while submicelles from small micelles reformed into small micelles.

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An autographic oscillatory damping meter was designed for the investigation of salt-induced gelation of myosin preparations. In the presence of 4.0 and 5.1M KSCN, the period of the oscillation system decreased to one half, to suggest that the dynamic rigidity would be increased abruptly, and the creep response of the displacement appeared below the rest point. These changes were more remarkable at 4.0M KSCN. In the presence of 3.0M LiBr, the time to a practical halt of oscillations decreased to one half, to suggest that the dynamic viscosity would be increased. At these salt concentrations, the helical contents of myosin were 33, 19, and 16%, respectively. Therefore it was concluded that a local melting of the helical structure might be related to salt-induced gelation.

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Heating followed by freezing and frozen storage of acid-precipitated protein caused an increase in the hardness of its gel in the presence of cetyltrimethylammonium bromide, acetylcholine bromide, choline chloride, and phosphatidylcholine dipalmitoyl, which all contain trimethylammonium residue. A comparison of the effect of choline chloride and ethanolamine chloride (a primary amine) suggests that trimethylammonium residue contributes to gel formation. When N-ethylmaleimide (NEM) was present, neither gel formation nor any action of trimethylammonium residue-containing compounds was observed. This result suggests that these compounds accelerate
interaction among the subunits through sulphydryl-disulphide interchange.

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The microbial transformation of cis-abienol and sclareol by a recently isolated soil bacterium, JTS-131, was studied. In the presence of metabolic inhibitors, three new compounds were isolated from the culture broth as degradation products of cis-abienol. They were determined to be (12Z)- labda-12, 14-dien-18-ol, (12Z)-labda-12, 14-dien-18-oic acid and its methylester. Two new compounds were also formed from sclareol in the presence of metabolic inhibitors. They were determined to be 13?A-hydroxylabd-14-en-18-oic acid and 13?A-hydroxylabd-14-en-18-oic acid methylester. As a result of sequence determination experiments, the biotransformation pathways of cis-abienol and sclareol by the bacterium were proposed.

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Pteridine reductase : dihydrofolate reductase obtained from Crithidia fasciculata was purified 60-fold. The molecular weight was estimated to be 110, 000 daltons by Sephadex G-150 gel filtration. The enzyme reduced the neopterin isomers (L-threo-, L-erythro-, D-hreo- and D-erythro-), 6-hydroxymethylpterin, 6-methylpterin and xanthopterin as well as dihydrofolate and dihydropteroate. The reaction with L-threo-neopterin had a double pH optimum (6.0 and 4.5), while that with 6-hydroxymethylpterin occurred over a pH range between 6.5 and 4.5. The optimum pH's using dihydrofolate and dihydropteroate as the substrates were 6.8 and 7.0, respectively. Km values for L-threo-neopterin, 6-hydroxymethylpterin, dihydrofolate and dihydropteroate were 3.5, 3.4, 4.8 and 0.9?EM, respectively. The reaction was dependent on NADPH, requiring two mol of NADPH
for reduction of one mol of L-threo-neopterin. Km values for the NADPH in assays with L-threo-neopterin, 6-hydroxymethylpterin, dihydrofolate and dihydropteroate were 11, 5.9, 5.9 and 2.1?EM, respectively. The reaction product was the tetrahydro form of each pteridine compound. Enzyme activity was inhibited by biopterin, folate, methotrexate, pyrimethamine, trimethoprim and NADP, as well as by p-chloromercuribenzoate, N-ethylmaleimide and urea. These evidences suggest that this enzyme is a new type of dihydrofolate reductase. Thus, the name, pteridine reductase : dihydrofolate reductase, is suggested for this enzyme.

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Conditions for protoplast formation and cell wall regeneration of Streptococcus lactis were described. Since S. lactis was relatively resistant to the action of lysozyme, cell wall digestion was insufficient when the cells were treated with lysozyme alone. Protoplasts were obtained by treatment with lysozyme and a bacterial α-amylase preparation in Tris-HCl buffer containing 3Mm MgCl₂ and 20% sucrose. The number of remaining osmotically stable cells decreased to less than 9×10^-7. Regeneration was accomplished with a hypertonic medium that contained CaCl₂, MgCl₂, gelatin and sucrose. The frequency of regeneration of protoplasts to normal cells was 3-10% after 5-7 days incubation in the hypertonic medium.

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In order to clarify the relationships between the taste and chemical structures of naringin, neohesperidin and their dihydrochalcone (DHC) derivatives, the following glycosides were synthesized. Naringenin 7-O-(3-O-α-L-rhamnopyranosyl-β-D-glucopyranoside) (I), hesperetin 7-O-(3-O-α-L-rhamnopyranosyl-β-D-glucopyranoside) (II), naringenin 7-O-(4-O-α-L-rhamnopyranosyl- β-D-glucopyranoside) (III), hesperetin 7-O-(4-O-α-L-rhamnopyranosyl-β-D-glucopyranoside) (IV), naringenin DHC 4'-O-(3-O-α-L-rhamnopyranosyl-β-D-glucopyranoside) (V), hesperetin DHC 4'-O-(3-O-α-L-rhamnopyranosyl-β-D-glucopyranoside) (VI), naringenin DHC 4'-O-(4-O-α-L-rhamnopyranosyl-β- D-glucopyranoside) (VII), and hesperetin DHC 4'-O-(4-O-α-L-rhamnopyranosyl-β- D-glucopyranoside) (VIII). I, II, III and IV are 0.05, 0.05, 0.05 and 0.01 times as bitter as naringin whereas V, VI, VII and VIII are 0.3, 0.2, 0.2 and 0.2 times as sweet as naringin DHC. As a result, the α-(1-2) linkage in rhamnosylglucose seems to be an essential factor in eliciting the bitter and sweet taste in naringin, neohesperidin and their DHC glycosides.

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A thermophilic obligate methane-oxidizing bacterium, H-2, produced two kinds of extracellular acidic polysaccharides (Polymer I and Polymer II) from methane as a single carbon and energy source. The maximum total polysaccharide production was 1.8g, together with 3.6g of dry cells, per liter of the culture medium. Polymer I and Polymer II contained 37% and 56% of sugars, respectively, consisting of glucose, mannose, galactosamine and glucuronic acid. In addition, these polysaccharides contained about 38% and 30% of amino acids, respectively.

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A route for the stereoselective synthesis of N-(β-L-aspartyl)-α-D-glucopyranosylamine, a part structure of the nephritogenic glycopeptide, was developed by using 2, 3, 4, 6-tetra-O-benzyl-α-D-glucopyranosyl azide as a key intermediate.

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The optimum pH of glutamine synthetase varied with the type and concentration of divalent cation present : pH 7.0-8.0 with 30mM Mg²⁺, 6.0-7.0 with 30mM Mn²⁺ and 7.0-8.0 with 4mM Mn²⁺. The activity with 4mM Mn²⁺ at pH 7.0-8.0 was almost the same as that with 30mM Mg²⁺. Changes in Km values for substrates and in susceptibility to inhibition by certain metabolites were observed when 30mM Mg²⁺ was replaced by 4mM Mn²⁺. Addition of a small amount of Co²⁺ greatly stimulated the reaction rate in the presence of a suboptimal level of Mg²⁺. Optimum pH, Km values for substrates and the inhibitory effect of metabolites were also changed in the mixture of Mg²⁺ and Co²⁺. Glutamine synthetase was reactive toward hydroxylamine, methylamine and ethylamine under the standard conditions as well as toward ammonia, and similarly the kinetics of these reactions were altered by divalent cations. The reaction products, γ-glutamyl derivatives, were identified.

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The physicochemical and immunochemical properties of a thermo-labile antigen (TLA b) which is located on the cell surface were studied. The sedimentation constant (S_{20, w}), molecular weight with the sedimentation equilibrium method and intrinsic viscosity were 7.33S, 81, 000 and 0.0313 dl•g^-1, respectively. TLA b was composed of two identical subunits on the basis of N-terminal amino acid analysis. The circular dichroic (CD) spectrum of the TLA b had a negative maximum at around 218nm. TLA b was estimated to have at least twelve antigenic d terminants by analysis of the quantitative precipitin reaction. The number of molecules of TLA b per cell was
estimated to be 5.65×10⁶, this corresponded to 1.14% by weight of the fresh yeast.

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Trimeric lignin model compounds, arylglycerol-β-syringaresinol ethers, were incubated with
Fusarium solani M-13-1 in basal salts medium with shaking. From the culture filtrates, degradation products were isolated and characterized spectroscopically. Based on the degradation products of guaiacylglycerol-β-syringaresinol ether (II), the following reactions were found to occur ; 1) oxidation of benzylic position (α") and subsequent ring opening of the syringaresinol side chain, 2) cleavage of alkyl-aryl C-C bonds (C_α-C₁ and C_α"-C_1") of both arylglycerol and syringaresinol portions, and 3) splitting of the alkyl-aryl ether bond (C_β-O-C_4') . In the case of syringlyglycerol-β- syringaresinol ether (III), preferential oxidation of benzylic position (α) of the arylglycerol moiety was seen. The former two reactions were found to be catalyzed by the fungal phenol oxidizing enzymes.

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In order to study the variability of intestinal transport systems for amino acid and peptide, the effects of quantity and quality of dietary protein on the absorption of L-leucine and glycylglycine were investigated in situ in the rat jejunum. The absorption activities for both amino acid and dipeptide changed in a similar manner in response to the dietary levels of casein ; decreasing below 10%, remaining nearly constant between 10 and 50%, and increasing above a 50% casein level. Similar results were obtained with wheat gluten. At an equal dietary protein level (equivalent to 10% casein), the absorption activities for L-leucine and glycylglycine in rats fed with a zein or gelatin diet were lower than those in animals fed with a casein or gluten diet. A high correlation was observed between the absorption activity for L-leucine and that for glycylglycine in all dietary groups. The results clearly indicate that jejunal absorption activity for glycylglycine could be altered in parallel with that for L-leucine by changes of the quantity and quality of dietary protein.

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The presence and levels of trans- and cis-ribosylzeatin, trans- and cis-zeatin, N⁶-isopentenyladenosine, and 6-(3-methyl-2-butenylamino)-9-?A-D-glucopyranosylpurine were determined in the root, and the stem and leaf of young sweet-potato plants by mass spectrometry using deuterium- labeled standards. The 6-(3-methyl-2-butenylamino)-9-?A-D-glucopyranosylpurine level was found to be the highest in both the root, and the stem and leaf. trans-Ribosylzeatin was present at a high level in the root. The ratio of the trans- and cis-isomers of zeatin in the root, and in the stem and leaf were determined to be 10 and 2.4, respectively. The variation in the trans/cis ratios of both zeatin and ribosylzeatin may reflect the growth stage of the organ in the plant.

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Critical micelle concentrations, micellar sizes and ellipticities at 220 nm were determined for sucrose monoesters of caprylic, capric and lauric acids. The interaction of these esters with proteins were also studied. The sucrose esters of caprylic and capric acids were found to bind only at discrete binding sites of native bovine serum albumin and this binding did not induce any detectable change in the protein conformation, while virtually no binding of the ligands to ovalbumin was observed, which lacks strong affinity sites in its native state. Together with the results of thermal denaturation experiments of the proteins in the presence of detergents, the present results indicate that the mode of interaction of sucrose esters with the proteins is quite similar to that of Triton X-100, a widely used nonionic detergent. Furthermore, it is suggested that the sucrose esters of caprylic and capric acids might be promising detergents for use in membrane protein research.

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A centrifugal liquid chromatograph was used to isolate the neutral lipids of rice-bran oil and corresponding model compounds. A rapid, clear-cut separation of the neutral lipids was obtained; the order of elutions was the same as that of liquid column chromatography. This report presents a brief discussion on the use of centrifugal liquid chromatography for the separation of neutral lipids.

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Eleven new O-methyl P-(dichloromethyl)phosphonamidates and ten corresponding diamides have been prepared and screened for their plant growth inhibitory and herbicidal activities. Structure activity relationships for both series of compounds are discussed.

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The fermented product of small shrimp was prepared with salt contents of about 20% at a temperature of 20±2°C for three months. The odor concentrates of the raw material and fermented product were obtained by simultaneous distillation and extraction with Nickerson's apparatus. Forty and thirty eight components were identified in the raw material and fermented product respectively by GC and GC-MS. The components identified included fifteen nitrogen-containing compounds (9 pyrazines, 3 pyridines and the others), eleven sulfur-containing compounds (3 thialdines, 3 thiazoles, 2 trithiolanes and the others), three ketones, four alcohols, two aldehydes and five other compounds. The sulfur compounds and pyrazines seem to be important contributors to the cooked odor of the fermented product.

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Volatile components in neutral, basic, phenolic and acidic fractions of the steam-distillate and in headspace gas trapped from two varieties of fully ripe tomato fruits and their juices, purées and pastes were analyzed by GC and GC-MS using a glass capillary column. One hundred and fifty-four compounds were identified : they were 3 sulfides, 10 aromatic hydrocarbons, 4 terpene hydrocarbons, 27 alcohols, 26 aldehydes, 13 ketones, 17 esters, 2 lactones, 7 furans, 4 pyrroles, 2 pyridines, 2 pyrazines, 2 thiazoles, 12 phenols, 16 carboxylic acids and 7 others. Of these, 39 compounds were identified for the first time in tomato fruits and their products.
Generally, with the advance of the processing degree from tomato fruits to pastes, decrement of low-boiling components and increment of middle to high-boiling components were observed. In tomato purées and pastes, 14 components, which were detected in tomato fruits and juices, disappeared and 11 components, pyrrole, 2, 5-dimethylpyrrole, 2-acetylpyrrole, 2-formylpyrrole, 2-methylpyrazine, 2, 6-dimethylpyrazine, dibenzofuran, o-phenylanisole, farnesol, indole and diphenylamine, were newly produced. 2-Acetylpyrrole, 2-formylpyrrole and the above pyrazines, which have respectively a burnt odor, are considered to be important for the characteristic heated aroma of tomato purée and paste.

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A new type of phenolic diterpene lactone, named rosmadial (1), was isolated from the leaves of rosemary (Rosmarinus officinalis L.), one of the herb spices belonging to the Family Labiatae. The structure has been determined to be 12-hydroxy-6, 7-seco-11, 10-epoxymethano-20-oxo-abieta- 8, 11, 13-triene-6, 7-dial by chemical and spectroscopic methods. The structure and stereochemistry were confirmed by synthesis from carnosol (5).

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The inactivation of glucose isomerase by radiolytically generated radical anions was investigated. In a pure solution of the enzyme at pH 7.0, Br^- had a pronounced radiosensitizing action whereas CNS^- had a protective action. The Br^- did not sensitize the inactivation of the enzyme irradiated at higher pH levels. From these results, it was estimated that the histidine residue is essential for the activity of glucose isomerase. The inactivation of the enzyme with diethylpyrocarbonate, which is a selective modification reagent of histidine residues, supports this estimation.
The inactivation of glucose isomerase in the Streptomyces cell was also accelerated markedly by Br^-. KCNS, tert-BuOH and O₂, which all had a protective action in vitro, accelerated the inactivation in vivo, although the sensitizations were smaller than that of Br^-. Since these materials could not directly attack the active site of glucose isomerase, the inactivation would be accelerated by indirect action such as a destruction of the protective substances in the cell.

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The presence of base-hydrolyzable conjugates of abscisic acid metabolites in fruits was examined using HPLC. Among the fruits investigated, avocado (Persia americana) was shown to contain a new conjugate of dihydrophaseic acid. The conjugate was identified as dihydrophaseic acid-4'-O-β-glucoside.

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Under meal-feeding conditions, supplementary tryptophan in a protein-free diet did not aggregate hepatic ribosomes, while the supplementation of methionine and threonine to the protein-free diet aggregated the ribosomes as compared with that in rats fed the protein-free diet. Under long-fasting conditions, this effect of methionine and threonine on polysomal aggregation disappeared. Intubation of tryptophan caused the aggregation of hepatic ribosomes, especially in fasted rats, and this aggregation with tryptophan disappeared on simultaneous administration of glucose, and then serum glucocorticoid was significantly enhanced but serum insulin was not changed. With single addition of tryptophan, methionine, threonine or leucine, serum glucocorticoid was enhanced in all groups but polysome aggregation was observed with only tryptophan addition. These results suggested that, although the intubation of tryptophan or another amino acid to long-fasted rats induced the increase of serum glucocorticoid which causes the degradation of extrahepatic tissue proteins, tryptophan might be the first limiting amino acid of endogenous amino acids in fasting conditions and consequently enhances the hepatic ribosome aggregation. In meal-feeding or ad libitum feeding of a protein-free diet, methionine and threonine might be the more limiting amino acids.

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The unsaponifiable matter from the marine red alga Porphyra tenera (asakusa-nori) did not show such stimulation as observed previously with hiziki (brown alga Hizikia fusiformis), but rather a slight inhibition on the porcine pancreatic carboxylesterase activity toward triacetin in vitro. Nine fractions obtained from the unsaponifiable matter by thin-layer chromatography were found to be divisible into two groups : an activator group and a non-activator group, which was not detected in hiziki. The addition of a non-activator fraction to an activator fraction abolished the activation activity. In addition, one of the active principles in the activator fraction of the purple laver was identified as phytol, as is the case with hiziki. These findings suggest that non-stimulation by the whole unsaponifiable matter must be due to masking of the activity of the activators by the non-activators.

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Both enantiomers of phoracantholide I and J were synthesized from a chiral starting material obtainable via yeast reduction, and the absolute configurations of the natural materials were determined by GLC studies using a chiral stationary phase.

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Physicochemical properties of heat-induced soluble aggregates of bovine globin were studied with several physicochemical measurements and electron microscopy.
A great change in ellipticity and formation of soluble aggregates of globin occurred between 45 and 50°C.
Soluble aggregates of globin formed below 60°C were globular particles with a diameter of 15 to 20nm and a sedimentation coefficient and molecular weight of approx. 20S and 8×10⁵, respectively. Their solutions were not so highly viscous. On the other hand, soluble aggregates of globin formed above 80°C were fibrous macro-aggregates with a thickness of 8 to 10nm of which the sedimentation coefficient and molecular weight were above 50 S and 10⁶ to 10⁸, respectively. Their solutions were highly viscous.
It is suggested that a great increase in globin viscosity on heating takes place through the following process ; globular aggregates are formed spontaneously with the unfolding of globin molecules, and subsequently fibrous macro-aggregates are formed via extension and association of globular aggregates. It is also considered that fibrous macro-aggregates might form a gel at a higher concentration.

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Di-D-fructose anhydride III has been isolated from inulin digested by a root-homogenate of Lycoris radiata. Identification of the compound was based on crystallization, mp, mixed mp, specific rotation and IR spectrum. The results strongly suggested the existence of inulin fructotransferase activity in the root of Lycoris radiata.

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Double-stranded cDNAs were synthesized using total polyA-containing mRNAs isolated from the mammary gland of a lactating cow as templates. Escherichia coli χ1776 was transformed with the hybrid DNA of bacterial plasmid pBR322 and cDNA constructed by the dG-dC tailing method. Plasmids containing cDNA inserts at the Pst I restri tion sites were selected by resistance to tetracycline and by sensitivity to ampicillin. Those containing milk protein cDNA sequences were selected by colony hybridization using radioactive (³²P) single-stranded cDNAs as probes. Recombinant plasmids were isolated from those clones showing intense signals on the auto-radiograph, and grouped into roughly six types by restriction endonuclease cleavage patterns of the cDNA sequences. Partial nucleotide sequences of two types of clones were determined by the method of Maxam and Gilbert. The amino acid sequence predicted from the nucleotide sequence of one clone coincided with that of α_s1-casein, a major component of bovine milk protein. The cloned cDNA sequence is 900 nucleotides in length, but may lack a DNA sequence coding the N-terminal region as well as the signal sequence of α_s1-casein.

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