It was found that the precursor of the sunstruck flavor was formed in the course of maturing sake cake. A large quantity of yeasts in the sake cake was autolysed and VB₂ was evolved. Like the sunstruck flavor of milk reported by Patton et al. it is thought that, VB₂, a photochemical sensitization substance caused methionine to react photochemically and to evolve the sunstruck flavor 3-(methylthio)-propanal (methional). Organoleptically, vinegar with added methional an vinegar which had evolved the sunstruck flavor had the same odor.

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As a potent producer of peroxidized flavor, Acetobacter No. 112 was selected out of 103 strains. This Acetobacter No. 112 was classified according to Bergey's, Frateur's and Yamada's methods and identified ad Acetobacter xylinum. The peroxidized flavor was generated only in the nedium containing acetic acid. It was clarified by GC/MS that the compounds of peroxidized flavor were propionic acid, isobutyric acid etc. Non-volatile acids were analyzed by liquid chromatography. Gluconic and oxalic acids were found in greater amounts in vinegar brewed by shaking culture, malic and citric acids were predominant in peroxidized vinegar, and glycollic and lactic acids were predominant in vinegar brewed by surface culture.

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The binding of Ca²⁺ ions and Ca-induced change in the hydration of F-actin were studied by a potentiometric technique using Ca sensitive electrode and sound velocity measurement. F-actin bound larger amounts of Ca²⁺ ions than lysozyme and ovalbumin. Hydration of both F-actin and ovalbumin decreased with addition of small amounts of Ca²⁺ ions such as 20 μM, but the decrease of hydration in F-actin was larger than that of ovalbumin. Bound ADP of F-actin was suggested to the cause of this phenomenon.

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A group of rats weighing about 120g were killed at the beginning of the experiment and after 10 days on the 20% casein diet (C-0 and C-10 groups), and another group of rats were killed after 1, 2 and 10 days on the protein-free diet (PF-1, PF-2 and PF-10 groups). From muscle and the liver of each group ribosomes were prepared, and the protein synthesis activity and the polysome patterns were investigated. The activity of polysome fractionated into each size was also measured.
Muscle ribosome activity in PF-1, PF-2 and PF-10 groups decreased to about 60%, 40% and 40% of that in C groups, respectively, and this decrease was due to a fall in activity of polysome itself rather than disaggregation of polysome. Liver ribosome activity in PF-1, PF-2 and PF-10 groups were reduced to about 95%, 90% and 65% of that in C groups, respectively. These alterations in PF-1 and PF-2 groups seemed to be in part related to changes in polysome pattern, whereas ribosome activity in PF-10 group was reduced without changes in polysome pattern.

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The partial structure of a spore germination inhibitor from a cellular slime mold, Dictyostelium descoideum was investigated. The molecular weight of this substance is 412 daltons. It contains at least N-(3-methyl-2-butenyl) adenine and an unknown α-amino acid residue. At the concentration of _??_0.03 μg/ml (_??_10^-8M), this compound completely inhibited the spore germination of this organism.

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An enzyme preparation catalyzing p-nitroaniline release from γ-glutamyl-p-nitroanilide was obtained in a 200-fold purified state from fruit bodies of an edible mushroom, Lentinus edodes. Analysis of the final preparation by differential centrifugation revealed that the enzyme was still bound with subcellular particles. The enzyme catalyzed both the hydrolysis and transfer of the γ-glutamyl moiety from γ-glutamyl-p-nitroanilide, but exhibited essentially no activity of glutaminase, glutamine aminotransferase, glutamine synthetase or γ-glutamyl cyclotransferase. With γ-glutamyl-p-nitroanilide the activity was maximal at about pH 7.6. The enzyme activity increased with an increasing concentration of Tris-HCl buffer, but not with phosphate buffer which was inhibitory. An apparent Michaelis constant of 4mM was obtained in 0.5M Tris-HCl buffer at pH 7.6. S-Alkylcysteine sulfoxide served as the best glutamyl acceptor. A serine-borate mixture, pCMB, Cu²⁺, Hg²⁺ and Zn²⁺ were potent inhibitors. All the experimental results, including the insoluble nature of the enzyme, allowed us to classify the Lentinus enzyme in the family of γ-glutamyl transferase.

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With lentinic acid as the substrate, γ-glutamyltransferase from Lentinus edodes catalyzed both hydrolytic and transfer reactions in the early stages of incubation. Prolonged incubation led to the exclusive formation of free glutamic acid and desglutamyl lentinic acid irrespective of the presence or absence of an added acceptor amino acid. The hydrolytic activity was at a maximum around pH 6.5, while the transfer activity increased with an increasing pH, reaching a constant level above pH 9.0. The pH-activity profiles of the respective reactions were interpreted as having an α-amino group of the enzyme protein functioning as a primary determinant of the reaction pathways. An apparent Michaelis constant of about 2mM was obtained when the transferase reaction was coupled with the high activity of alliin lyase. Prima facie evidence is given for the function of the γ-glutamyltransferase involved in the lenthionine evolution mechanism from lentinic acid.

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A soluble enzyme acting on S-alkyl-L-cysteine sulfoxide and cystine was found in fruit bodies of Lentinus edodes, and partially purified by ammonium sulfate fraction, DEAE-cellulose chromatography and Sephadex G-200 gel filtration. The enzyme preparation exhibited a high activity over weakly alkaline pH regions and required pyridoxal 5'-phosphate as cofactor. The enzyme catalyzed decomposition of a number of cysteine sulfoxides (or cystine) into pyruvic acid, ammonia, thiolsulfinate (or persulfide). An apparent Michaelis constant was approximately 2.5mM with (±) S-ethyl-L-cysteine sulfoxide. Lentinic acid, a principal endogenous precursor for lenthionine, did not serve as the substrate for the purified enzyme but underwent the C-S lyase action to form lenthionine when coupled with γ-glutamyl transpeptidase. In the presence of hydroxylamine, the Lentinus enzyme preparation lost the aroma formation ability from lentinic acid and desglutamyl lentinic acid accumulated quantitatively. An enzyme preparation from Allium species acted on desglutamyl lentinic acid in the same way as the Lentinus enzyme. These findings are consistent with the function of cysteine sulfoxide lyase in the sequence of the lenthionine formation from lentinic acid.

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Poly (A) took stable double-stranded form in 0.02M phosphate buffer pH 5.8 when its S-value was higher than 3.5. Poly (C) also took stable double-stranded form in 0.01M acetate buffer pH 3.9 containing 0.1M NaCl if its S-value was higher than 4.8.
Poly (I) with S-values higher than 6.5 stably formed triple-stranded form. Poly (A) with S-values over 3 S and poly (I) with S-values over 7 S were observed to aggregate in the presence of high concentration of salt, but poly (C) and poly (U) did not aggregate under the same condition. Effect of salt concentration differed with different polynucleotides and with different salts.

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The action of P₂O₅ in DMSO on methyl α-D-glucopyranoside, sucrose and trehalose afforded nondializable, phosphorylated glycans in 6_??_34% yields. Polysucrose has a molecular weight of _??_9, 500. The synthetic glycans consist of carbohydrate (46_??_59%) and P (11.4_??_13.1%) and show reducing sugar values (5.0_??_30.8%). The alkaline hydrolysis of polysucrose was accompanied with a depolymerization and afforded sugar phosphates and oligosaccharides. The periodate oxidation gave formic acid (0.15_??_0.34 mole) and formaldehyde (0.07_??_0.17 mole/monosaccharide residue). The methylation study indicated their variously branched structures. 2, 3, 4, 6-Tetra-O-methyl-D-glucose was found in only 0.7_??_3.2% yields, and this is in agreement with their weak precipitation reactions with Con A. It is considered that the glycans are produced from nonreducing mono- and oligosaccharides by dehydration, transglycosidation and esterification with phosphate.

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A small amount of the component accompanied with human chorionic somatomammotropin has been separated on Sephadex ion exchanger. When polyacrylamide disc gel electrophoresis was performed at pH 9.3, the two bands were very close each other in electrophoretic mobility. They possess lacogenic activity for the pigeon crop sac test. A comparison of their physicochemical properties was made. The major component was in excellent agreement with the minor more acidic component in amino acid analyses, N-terminal amino acid analyses and circular dichroism studies. Immunological studies indicated some common properties between them, whereas they differed significantly in the electrophoretic mobility of precipitin arc.

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Aspergillus niger (AKU 3302) degraded NAD to form Compound X. This compound was identified as nicotinamide ribose diphosphate ribose (NAmRDPR) by hydrolysis with alkaline or phosphodiesterase followed by chemical analysis of the products. NAmRDPR showed absorption maxima at 265_??_266 nm in 0.1 N HCl and 325 nm in 1.0 N KCN. Optimal pH for NAmRDPR formation by the enzyme preparation from this organism was around 4.0. Formation of NAmRDPR proceeded stoichiometrically with degradation of NAD. Some of other strains of A. niger formed NAmRDPR, but production of this compound was not demonstrated in other mold genera.

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An extremely purified preparation of an exo α-1, 2-mannanase (EC. 3. 2. 1. 24) has been obtained from the culture filtrate of Flavobacterium dormitator var. glucanolyticae by using yeast mannan as substrate. The molecular weight of the enzyme was estimated to be 900, 000. The enzyme showed pH optimum of 7.0 and was stable at pH 6.0. The Km value of the enzyme for yeast mannan was 0.16%. The enzyme did not seem to be Zn²⁺-dependent and was highly specific for α-1, 2-mannosidic bonds in yeast mannan.

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Some physico-chemical properties of nuclease P₁ (isoelectric point, 4.5) from Penicillium citrinum were studied. The extinction coefficient at 280 nm, E^1%_1cm, was 18.4. The partial specific volume (_??_), the intrinsic viscosity ([η]), the sedimentation coefficient (s⁰_{20, w}) and the diffusion coefficient (D_{20, w}) were 0.712ml/g, 4.17×10^-2ml/g, 3.55 S and 7.4×10^-7cm²/sec, respectively.
The molecular weight was estimated to be 42, 000_??_50, 000 by several methods including sedimentation velocity, sedimentation equilibrium, gel filtration and SDS-acrylamide gel electrophoresis. The amino acid composition of the enzyme was characterized by the high content of hydrophobic amino acids, especially tyrosine and tryptophan. The enzyme was found to be a zinc metalloenzyme which contained 3 gram atoms of zinc per mole based upon the molecular weight of 44, 000. The enzyme also contained about 17.4% carbohydrates, consisting of mannose, galactose and glucosamine in a molar ratio of 6:2:1. The enzyme exhibited a high affinity for concanavalin A-Sepharose, suggesting the enzyme is a glycoprotein.

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During and examination of components contributing to the bitter taste of asparagus bottom cut (Asparagus officinalis L.) two new furostanol saponins were isolated from roots extractives. Their chemical structures were established as 5β-furostane-3β, 22, 26 triol-3-O-β-D-glucopyranosyl (1→2)-β-D-glucopyranoside 26-O-β-D-glucopyranoside and 5β-furostane-3β, 22, 26 triol-3-O-β-D-glucopyranosyl (1→2) [β-D-xylopyranoxyl (1→4)]-β-D-glucopyranoside 26-O-β-D-glucopyranoside respectively.

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Cultured broths were screened by measuring the inhibition of glyoxalse, using 105, 000g supernatant of rat liver homogenates as a crude enzyme. An active agent, MS-3 (C₂₁H₂₄O₇), was isolated from a cultured mushroom. ID₅₀ value of MS-3 against the crude glyoxalase was 12 mcg/ml. MS-3 has low toxicity and inhibited the growth of Yoshida rat sarcoma cells in cell culture. The production, isolation, and properties of MS-3 are described.

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The structure of MS-3, a glyoxalase I inhibitor produced by a mushroom, was established to be 3', 4'-dihydroxymenthyl-5'-hydroxy-6'-(3-methyl-2-butenyl)-phenyl-2, 4-dihydroxy-6-methyl-benzoate.

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Cytosine deaminase from Pseudomonas aureofaciens was purified about 480-fold by means of ammonium sulfate fractionation, ethyl alcohol fractionation, chromatography on columns of DEAE-Sephadex A-50 and hydroxylapatite and by gel filtration on a Sephadex G-200 column. The enzyme was homogeneous by the criteria of sedimentation and electrophoretic analysis. The molecular weight of the purified enzyme was estimated to be 630, 000 by gel filtration and consisted of twelve to sixteen identical subunits having a molecular weight of about 45, 000. The enzyme catalyzed the deamination of cytosine and 5-methylcytosine.

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Two water soluble hemolysins isolated from the green alga Ulva pertusa have been identified as 1'-O-palmitoyl-3'-O-(6-O-α-D-galactopyranosyl-β-D-galactopyranosyl)-glycerol (1) and 1'-O-palmitoyl-3'-O-(6-sulfo-O-α-D-quinovopyranosyl)-glycerol (2).

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The primary stable products, methyl linoleate monohydroperoxides (MLHPO), formed by the autoxidation of methyl linoleate were characterized by gas chromatography-mass spectrometry. MLHPO was converted into methyl hydroxy stearates which consisted of two isomers, methyl 9-ghydroxy and methyl 13-hydroxy stearate. Trimethylsilyl ether derivatives of these hydroxy isomers were separated directly by gas chromatography and mass fragmentgraphy. MLHPO was degradated by incubating under aerobic condition at 37°C for a week, and the quantity of MLHPO was determined as hydroxy derivatives. Decrease of MLHPO was almost similar to that of conjugated diene structure, but the peroxide value was not appreciably decreased during the incubation. This fact based on the formation of further oxygenated compounds. After chemical reduction, these compounds were identified as methyl 9, 13-hydroxy octadecenoate and methyl 9, 12, 13- or 9, 10, 13-trihydroxy octadecenoate, in which oxygen attached to the conjugated diene. The formation mechanisms of these oxygenated compounds are proposed.

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Previously a cyclic pathway for the partial oxidation of propionyl-CoA to pyruvate has been proposed. Enzymatic evidence for the presence of the key reactions involved in this pathway is described and discussed herein. The condensation of propionyl-CoA with oxaloacetate into methylcitate is shown to be catalyzed by an enzyme contained in cell-free extracts of Candida lipolytica; the enzyme seems to differ from the usual citrate synthase. Methylcitrate is easily convertible to a mixture of C₇-acids by the action of cell-free extract of the mutant strain. On the other hand, a similar mixture is changed into pyruvate and succinate by the action of cell-free extract of the parent strain. Evidence is given that methyl-isocitrate, one of the products of the conversion, is mainly cleaved by the action of an additional enzyme other than the usual isocitrate lyase. The accumulation of methylisocitrate in a large amount from odd-carbon n-alkanes by the mutant strain can be safely ascribed to the absence or a low level of this enzyme in the mutant strain.

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Existence of an acetyltransferase, which catalizes acetylation of deacetylcephalosporin C to cephalosporin C, was demonstrated for the first time in cell-free extracts of Cephalosporium acremonium. The pH optimum of the enzyme appeared to be 7.0 to 7.5 and the enzyme required essentially Mg²⁺ as a cofactor for its reaction. The activity of this enzyme was not observed in the cell-free extracts of deacetylcephalosporin C-producing mutants Nos. 20, 29, 36 and 40, but was recovered in a revertant obtained from the mutant No. 40. These results indicate that deacetylcephalosporin C accumulation by these mutants was due to the lack of the acetyltransferase and made it reasonable that the terminal reaction of cephalosporin C biosynthesis in Cephalosporium acremonium proceeded by the catalytic action of acetyltransferase.

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Deacetylcephalosporin C negative mutants, lacking a certain step in the pathway of deacetylcephalosporin C biosynthesis, were obtained from the deacetylcephalosporin C producing mutant No. 40 of Cephalosporium acremonium by treatment with N-methyl-N'-nitro-N-nitrosoguanidine. Among these mutants, the strain No. 40-20 was found to mainly accumulate a cephalosporin compound other than deacetylcephalosporin C and cephalosporin C. The cephalosporin was isolated as crystals from the culture broth of the mutant No. 40-20, and identified as deacetoxycephalosporin C, possessing a D-α-aminoadipyl side chain at C-7, by physical, chemical and biological methods. The profile of deacetoxycephalosporin C fermentation and the examination of the biochemical reduction of deacetylcephalosporin C led us to the conclusion that deacetoxycephalosporin C would be produced through de novo synthesis by this mutant.

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The deoxyribonucleic acid (DNA) polymerases were partially purified from spores and vegetative cells of Bacillus subtilis. Some biochemical properties of the enzymes from the spores were studied in comparison with those from the vegetative cells. The spores and vegetative cells had at least three species of DNA polymerases (DNA polymerase I, II and III). These DNA polymerases in spores could not be distinguished from those in vegetative cells, respectively, with regard to the reresponses to ionic strength, the sensitivity to thiol-blocking agents, the template specificity, pH and temperature optima in assay, and the sedimentation behavior. It is inferred that DNA polymerases from spores was essentially identical to those from vegetative cells.
The DNA polymerase activity decreased rapidly in the course of sporulation, and only about 20% is recovered in the spores, suggesting that an extentive inactivation mechanism of the enzymes would be involved during sporulation.

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The enantioselective addition of chiral benzylic amines to dimethyl maleate and fumarate gives optically active aspartic acid in satisfactory yields. The re-face favorably meets the stereochemical requirements of the chiral R-amines than does the si-face. The stereoselectivity in the present reaction is little dependent on solvent polarity but is significantly enhanced by low temperature. The direct determination by gas-liquid chromatography of the diastereomeric addition products provides more precise values of optical yield and is preferred to the polarimetry of the end product after many steps of transformation with probable fractionations.

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