Upon incubation with lytic enzymes, the antigenic activity of the cell surface of baker's yeast was decreased. Some antigens were released from the cell even when lysis of the yeast cell had not occurred. Thus the relation between retention of antigenic activity on the cell surface and susceptibility to lytic enzymes was investigated with yeast cells treated with heat, 2-mercaptoethanol, sodium periodate, several aldehydes, diethyl pyrocarbonate, acetic acid and acetone. The results revealed that susceptibility of the cell surface to lytic enzymes and antigenicity were greatly dependent on the physical and chemical status of either the mannan layer or cell membrane.

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Headspace gas and ether extract of sliced or homogenized onion were analyzed by using GLC. Dialkyl disulfides, main components of characteristic flavor of sliced onion, were found to be very little when onion was homogenized. Addtion of NaBH₄ to the homogenate resulted in a marked production of disulfides while that of cysteine did not. SH compounds as cysteine and benzyl mercaptan were added to the homogenate to determine the intermediates which produced flavor with NaBH₄. The presence of propyl propanethiosulfinate, propanal and thiopropanal S-oxide was confirmed by isolation and identification of their sulfide derivatives.

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The phosphatase activity of intact cells of inositol-exacting strains increased apparently during inositol-deficiency. This increased activity of phosphatase was found at a wide pH range. The solubilized enzymes prepared from cells showed no notable difference between inositol-deficiency and sufficiency. Some fractions of released polysaccharide samples partially inhibited phosphatase activity at pH 8_??_9, and activated it at pH 4. The results suggest that the polysaccharide (released fraction) may be related to the cell-wall and phosphatases. This inositol-deficiency-induced activation of phosphatases may not need newly synthesized protein. Inositol-deficiency might induce an abnormal cellular structure which results in the changed permeability and unmasking of the phosphatase activities.

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API-2c, one of the alkaline protease inhibitors produced by Streptomvices griseoincarnatus strain No. KTo-250, interacts with subtilisin BPN'. The API-2c-subtilisin BPN' complex was isolated by gel filtration on Sephadex G-100. Its homogeneity was determined by disc electrophoresis. From the results of molecular weight determination of the complex (MW 86, 000) and of inhibitory assay of the API-2c released from the complex, it was shown that the complex was composed of one mole (two subunits) of API-2c and two moles of subtilisin BPN'.
The inhibitory activity was gradually released from the complex by dialysis against 0.05 N HCl at 4°C. The inhibitor released showed a different mobility from virgin API-2c. These results suggest that APT-2c was mndified to APT-2c^* which peptide linkaee in the reactive site was specifically cleaved.

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The inhibitory activity of API-2c was reduced by carboxymethylation of methionine residues but not by chemical modifications of lysine and arginine residues. This indicates that API-2c requires methionine residue for inhibitory activity. Dissociation of API-2c-subtilisin BPN' complex under mild conditions (pH-gradient dialysis) resulted in the conversion of API-2c to modified form (API-2c^*).
The amino acid composition of API-2c did not change upon enzymatic modification. However, modified API-2c had two NH₂-terminal sequences (Asp-Ser-Pro- and Ile-Tyr-Asp-) and two COOH-termini (Phe and Met), and gave two bands on SDS-polyacrylamide gel disc electrophoresis after reduction of disulfide bonds by 2-mercaptoethanol. From these results, it is concluded that the Met-Ile bond located within a disulfide bridge in API-2c molecule is the reactive site for inhibi-tion of subtilisin BPN'.

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Chromatographically homogeneous phosphatidylcholine identified by thin-layer chromatog-raphy on silica gel G was isolated from mycelia of Aspergillus oryzae or egg yolk by a combination of alumina and silicic acid column chromatography. Although the 2-position in both Asp. oryzae- and egg yolk-phosphatidylcholine was occupied nearly exclusively by unsaturated fatty acids, significant proportions of unsaturated fatty acids were also found in the 1-position of Asp. oryzae-phosphatidylcholine. In nitrogen gas-sparging anaerobic culture of Saccharomyces sake Kyokai No. 7, supplementing the basal synthetic medium with phosphatidylcholine enhanced the yeast growth and fermentative activity, whereas adding ergosteryl oleate enhanced alcohol-endurability. Supplementation with both phosphatidylcholine and ergosteryl oleate promoted the yeast growth, fermentative activity and alcohol-endurability of cells.

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The activity of nitrogenase and the concentration of ammonia and allantoin (+allantoic acid) in root nodules were measured throughout the growth period of soybean plants. Nitrogenase activity measured by acetylene reduction increased with plant growth and reached a maximum level at the flowering period. The level of ammonia and allantoin concentration in nodules was parallel with increased nitrogenase activity. At the late reproductive stage (pod-forming period), nitrogenase activity showed a marked decrease, but the ammonia and allantoin in the nodules remained at a constant level. Detached nodules from 56 day-old soybean plants were exposed to ¹⁵N₂ gas, and the distribution of 15^N among nitrogen compounds was investigated. Enrichment of ¹⁵N in allantoin and allantoic acid reached a fairly high level after 90min of nitrogen fixation; ca. 22% of ¹⁵N in acid-soluble nitrogen compounds was incorporated into allantoin + allantoic acid. In contrast, enrichment of 15N in amide nitrogen was relatively low. No significant ¹⁵N was detected in the RNA fraction. The data suggested that ureide formation in nitrogen-fixing root nodules did not take place through the breakdown of nucleic acids, but directly associated with the assimilating system of biologically fixed nitrogen.

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A product easily converted to glyoxal was found in an early stage of the reaction of sugar with amine in ethanol. Glyoxaldicyclohexylimine was isolated from the reaction mixture of D-glucose with cyclohexylamine. This finding suggested the formation of a similar type glyoxaldialkylimine in other reactions of sugar with amine. This two-carbon compound was assumed to be produced directly from sugar or glycosylamine, and a new pathway for sugar fragmentation was proposed.

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Four kinds of 4-substituted phenyl diethoxyphosphinyl disulfide (substituents: H, CH₃, C₂H₅, Cl) and phenyl diethoxyphosphinothioyl disulfide reacted readily with diazomethane. The phosphinyl disulfides produced diethyl (4-substituted phenylthio)methyl phosphorothionate and the isomer, diethyl S-(4-substituted phenylthio)methyl phosphorothiolate, as the main products, whereas the phosphinothioyl disulfide produced only diethyl S-(phenylthio)methyl phos-phorodithioate.
The possible mechanism involved is as follows: the S-S bond in (EtO)₂P(X)-S-S-C₆H₄R (X=O or S) is cleaved by nucleophilic attack of diazomethane at the sulfur atom bonded to the phenyl group to produce (EtO)₂P_??_and_??_N₂CH₂-S-C₆H₄R; the latter reacts with the former with loss of nitrogen; therefore, when X is O, two compounds, (EtO)₂P(S)-O-CH₂-S-C₆H₄R and (EtO)₂P(O)-S-CH₂-S-C₆H₄R, are produced, when X is S, only (EtO)₂P(S)-S-CH₂-S-C₆H₄R is obtained.

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Alginate lyase, SP2, from Turbo cornutus was separated on an SP-Sephadex C-50 column from SPI, whose properties have already been reported, and purified according to the method employed for SP1, to obtain information on SP2. The profiles of the optimal pH, pH-stability, thermal inactivation and molecular size of SP2 were entirely the same as those of SP1. The isoelectric point of SP1 and SP2 was 7.5 and 7.7, respectively. The action of SP2 on Alginate caused a rapid decrease in solution viscosity. Analysis of digestion products of alginate with SP2 showed that the enzyme had an affinity toward the mannuronate-rich domains of the alginate molecule and released unsaturated oligomers mostly composed of mannuronic acid as final product. Alginate lyases, SP1 and SP2, were shown to be isozymes in the mid-gut gland of Turbo cornutus.

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Various novel acyclic carboxylic acids were prepared and some of their 3-phenoxybenzyl esters were found to have slight insecticidal activity.

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Staphylococcal plasmids pTP4 (2.7 megadaltons encoding resistance to chloramphenicol) and pTP5 (2.6 megadaltons encoding resistance to tetracycline), which replicate and express resistance in B. subtilis, were found to cut by HindIII endonuclease respectively at a single site and three sites. A chimeric plasmid pTA1245 (4.1 megadaltons) was constructed from pTP4 and pTP5 by HindIII digestion and ligation with E. coli DNA ligase. pTA1245 expresses resistances to chloramphenicol and tetracycline in B. subtilis, and pTA 1245 is amplified in the presence of tetracycline. A physical map of pTA1245 was constructed.

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Short glycopeptides were prepared from bovine colostral k-casein treated with cyanogen bromide and proteases (pronase P and thermolysin), followed by gel filtrations and ion exchange chromatography. It was confirmed by Edman degradation that glycopeptide I among short glycopeptides obtained was homogeneous. From the effect of alkali treatment, it was assumed that three polysaccharide chains of glycopeptide I were attached to the peptide chain through OH groups of threonines. By chemical procedures and carboxypeptidase P treatment, the amino acid sequence of glycopeptide I was established to be Ser-Gly-Glu-Pro-Thr-Ser-Thr-Pro-Thr-Thr-Glu-Ala-Val. Threonine residues of No. 5, 7 and 9 were bound to the carbohydrate chains through galactosamine. The sugar chain bound to the threonine residue at No. 7 contained glucosamine, Glycopeptide I corresponded to residues of No. 127_??_139 in K-casein A from normal milk.

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Two host-specific pathotoxins, Band 1- and Band 2-toxins, were isolated from the toxin complex obtained from the culture broth and mycelial mat of Helminthosporium maydis, race T, the fungus causing Southern corn blight disease. Chemical and spectrometric studies showed them to be polyketo-polyhydroxy compounds with C₄₁ carbon chains. Band 2-toxin is identical to Band 1-toxin except that Band .2 toxin has an additional hydroxyl group in place of one of the keto-group of Band 1-toxin.

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An α-galactosidase from tubers of S. affinis was purified about 130 fold by ammonium sulfate fractionation, chromatography on DEAE-cellulose and gel filtration on Sephadex G-75. The purified enzyme showed a single protein band on disc gel electrophoresis. The molecular weight of the enzyme was determined to be approximately 42, 000 by gel filtration and 44, 000 by SDS disc gel electrophoresis. The optimum reaction pH was 5.2. The enzyme hydrolyzed raffinose more rapidly than planteose. The activation energy of raffinose and planteose by the enzyme was estimated to be 7.89 and 11.4 kcal/mol, respectively. The enzyme activity was inhibited by various galactosides and structural analogs of n-galactose. Besides hydrolytic activity, the enzyme also catalyzed the transfer reaction of D-galactosyl residue from raffinose to methanol.

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O, O-Dimethyl phosphorodithioate (DMDTP) is the raw material for such organophosphorus pesticides as malathion, dimethoate and cidial, and is abundant in wastewater of pesticide manufacturers. The activated sludge was acclimated to DMDTP by the fill-and-draw method. The acclimated, activated sludge degraded 500 mg/liter of DMDTP in 7 hr and as a result, produced 260mg/liter of inorganic orthophosphate and 510mg/liter of sulfate. The pH of the mixed liquor was adjusted to degrade DMDTP, and the optimum pH was from 6.5 to 7.0. The activated sludge acclimated to DMDTP degraded dimethyl phosphorothioate, dimethyl phosphate, diethyl phosphorodithioate and diethyl phosphate.

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Asymmetric hydrolysis of the acetates of(±)-cis and trans-carveols by microorganisms or their esterase produced chiral cis and trans-carveols and the acetates of their enantiomers. The enantioselectivity of the microbial hydrolysis and the optical purities of the products varied with the species of microorganisms. This method was also applied in separation of diastereomeric mixtures of (-)-carveols and (-)-7-epi-α-cyperols.

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The female sex pheromone of the oriental corn borer, Ostrinia furnacalis Guenee, was presumed to be composed of (Z)-12-tetradecenyl acetate and its geometrical isomer using electroantennogram technique. From the extracts of female moths, the presence of these compounds in a ratio of ca. 3:2 was confirmed by gas-liquid chromatography and gas-liquid chromatography combined with mass spectrometry in selected ion monitoring mode. Since the male moths were not attracted to mixtures of the two synthetic compounds, the presence of minor component(s) was suggested.

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Polyamine oxidase was purified and crystallized with an overall yield of 35% from mycelial extract of Penicillium chrysogenum by a procedure involving ammonium sulfate fractionation, and DEAE-cellulose and Sephadex G-200 column chromatographies. The crystalline enzyme was homogeneous, as judged by disc gel electrophoresis and ultracentrifugation. The sedimentation coefficient (s⁰_{20, w}) of the enzyme was determined to be 6.9S, and diffusion coefficient (D_{20, w}) to be 4.2×10^-7cm² sec^-1. The enzyme showed a molecular weight of about 160, 000 by gel filtration method and ultracentrifugal analysis, and it was composed of two identical subunits. The enzyme was a flavoprotein with absorption maxima at 275, 375 and 450nm. The prosthetic group was identified to be FAD. The enzyme oxidized spermine, and slightly oxidized spermidine. Diamines and monoamines were not oxidized.

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The distribution of acyl-CoA synthetase was investigated among microorganisms. High enzyme activity was found in some strains in genera of Pseudomonas, Fusarium, Gibberella and Cylindrocarpon, and in many strains of basidiomycetes. There were two groups in respect to enzyme formation. The enzyme activities of Escherichia, Klebsiella, Enterobacter, Citrobacter and Serratia were detected only when they were grown with fatty acids as the carbon source. On the other hand, the activities of many fungal strains and pseudomonads were easily detected regardless of the carbon source for growth.
Gel filtration on Sephadex G-200 showed that the enzymes of Escherichia coli and Gibberella fujikuroi were mostly present around the void volume of the column and retarded by the gel after treatment with Triton X-100. Pseudomonas aeruginosa produced two kinds of enzymes, one was eluted around the void volume of the column and the other retarded by the gel. This elution pattern did not change upon treatment with Triton X-100. Some catalytic properties of acyl-CoA synthetases from P. aeruginosa and G. fujikuroi were also described.

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Two sulfur containing peptides have been isolated from a cationic peptide-rich fraction of dried Lentinus edodes by chromatographic technic. They have been identified as γ-glutamylcystine and N, N-bis-γ-glutamylcystinylglycine based on chemical, chromatographic and spectroscopic properties.

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The available energy, gross protein value, phosphorus availability and palatability of 16 samples of single cell protein were evaluated in 20 bioassays using total 2, 136 depleted chicks.
Four protein samples were products from Aspergillus tamarii grown on waste water of a fish processing factory, three were from Aspergillus oryzae grown on either acetic acid medium or cooked soybean waste, three were from Candida sp. grown on citrus molasses extracted from peel wastes of citrus processing plants, four were from Candida utilis grown on wood molasses produced from various wood wastes, and two were from Pseudomonas sp. and Alteromonas thlasomethanolica grown on methanol.
Five of 16 samples had excellent nutritive value, comparable to single cell proteins available commercially in Europe. All samples were palatable to the chicks, and no sign of acute toxicity was observed.

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The cooked odor concentrate of boiled Antarctic krills was obtained by simultaneous distillation and extraction, in a modified Likens and Nickerson's apparatus. The sulfur containing fraction was successively separated with preparative gas chromatography. Organoleptically, this fraction seemed to play a significant role in the characteristic odor of cooked krills. The fraction was analyzed by a gas chromatograph equipped with FPD and FTD, and by GC-MS. Seven sulfur containing compounds and four containing both sulfur and nitrogen compounds were newly identified in the cooked odor of Antarctic krills. These compounds seem to be important contributors to the odor of cooked krills.

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Vitamin B₆ is synthesized by green Cytisus scoparius callus and green Phellodendron amurense callus cultured on Linsmaier and Skoog Agar-medium with 10^-5M of α-naphthaleneacetic acid (NAA) and 10^-6M of 6-benzyladenine (BA). Even when thiamine and inositol were omitted from this medium, the growth and vitamin B₆ content of Cytisus scoparius callus did not change. Vitamin B₆ contents of clones of the calluses varied and were unstable during long-term subculture. Clonal selection was repeated to obtain stable strains with high vitamin B₆ content, and the vitamin B₆ content of one strain of green Cytisus scoparius callus became 4-times higher than that of the green leaves.

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Two kinds of spherical mutants, mrdA and mrdB mutants, have been isolated from Escherichia coli strain K12. The mrdA mutants have thermosensitive penicillin-binding protein 2, while the mrdB mutants have normal penicillin-binding proteins. Both kinds of mutants form spherical cells at 42°C and are resistant to the amidinopenicillin, mecillinam, at the same temperature. The two mutations have been mapped very close to lip at 14.2min (revised chromosome linkage map, 1980) on the E. coli chromosome. Both mutations cause supersensitivities of cell growth to various β-lactam antibiotics, such as ampicillin, cephalexin, cefoxitin and nocardicin A at 42°C.

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Radiolysis of some monosaccharides (fructose, glucose and ribose) in air-free condition was markedly enhanced by the addition of formate at concentrations above 20mM, while it was inhibited at concentrations below 20mM. The following compounds were detected in the irradiated sugar solutions containing excess formate (100mM): 1-Deoxy-D-arabinohexulose (1, G=4.4) and 1, 3-dideoxy-D-erythrohexulose (2, G=1.3) from fructose; 2-deoxy-D-ribose (3, G=2.3) and 2-deoxyribitol (4, G=0.6) from ribose; and 2-deoxy-D-glucose (5, G=0.5) and 2-deoxy-D-glucitol (6, G=0.4) from glucose. A mechanism for radiolytic formation of the products was proposed, based on interaction of CO₂^- formed from formate with sugars.

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The erythrocytes and plasma of rats were not labeled equally with sterols even after feeding plant sterols for 2 months.
When erythrocytes and plasma were labeled in vivo with radioactive sterols, the in vitro exchange of cholesterol between cells and plasma was considerably greater than that of β-sitosterol. The dependence of the transfer on plasma lecithin: cholesterol acyltransferase was much less with β-sitosterol.
More labeled β-sitosterol existed in high density lipoprotein and less in very-low density and low density lipoproteins than cholesterol, when plasma was labeled in vivo. A similar distribution pattern was observed when plasma was incubated with labeled erythrocytes. These results suggest that an extra ethyl group in the side chain of the molecule substantially influences the metabolic behavior of the sterols.

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Some pyridyl terpenoid ether analogs of juvenile hormone were synthesized and tested for activity against stored-product insects. Compounds with a longer alkyl side chain were more active.

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¹⁴C-Labeled ribosyl-trans-zeatin and its cis isomer have been prepared from [8-¹⁴C] inosine by facile reactions.

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