Diethyl 2-methyl-3-oxosuccinate reductase was purified from cells of Saccharomyces fermentati by streptomycin treatment, Sephadex G-50 gel filtration, a first DEAE-cellulose chromatography, a first Toyopearl HW-60F gel filtration, a second DEAE-cellulose chromatography and a second Toyopearl HW-60F gel filtration. The enzyme was purified 169-fold and gave one band in sodium dodecyl sulfate(SDS)/polyacrylamide-gel electrophoresis. The molecular weight of the purified enzyme was 61, 000 to 63, 000. The enzyme was NADPH-dependent and had maximum activity at pH 6.0 and 50°C. It was stable at pH 7 to 8. The Km values at pH 7.0 were 1.25mM for diethyl 2-methyl-3-oxosuccinate and 111 mM for the α-methyl β-hydroxy esters syn-(2) and anti-(3). The enzyme reduced methyl 2-methyl-3-oxosuccinate, but did not act on other synthetic substrates.
The optical yields of the products syn-(2) and anti-(3) reduced by the purified enzyme were more than 99% enantiomer excess (e.e.) by measurement of the corresponding (+)-MTPA esters[syn-(10) and anti-(11)] on a 400 MHz NMR instrument.

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¹H-, ¹³C-, and ³¹P-NMR spectra of soybean seeds were examined in relation to the water contents to study physiological changes during the course of maturation. Two remarkable transitions were deduced from the NMR spectra; (1) the termination of vacuoler function before that of cytoplasmic function at the water content of 28%, (2) end of activity of cytoplasm at a water content of approximately 10%. Only the signals due to oils are observed other than water in dry seeds at the water content of 7%.

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The hydroperoxide of methyl linoleate containing 95% 13-hydroperoxide and 5% 9-hydroperoxide was decomposed in benzene with 10^-4M cupric naphthenate at 75-80°C under degassed conditions. The decomposition products were fractionated by Sephadex LH-20 column chromatography with chloroform-hexane (2:1, v/v) and the fractions were purified by HPLC. In addition to the known products, three compounds were identified as methyl 9-(2-(2, 5-dihydro-5-pentylfuryl))-nonanoate, methyl 8-(2-furyl)-octanoate, and methyl 9(13)-hydroperoxy-12, 13-(9, 10)-epoxy-10(12)-octadecenoate as miner decomposition products by MS and IR spectrophotometry.

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Bifidobacterium breve 203 grew well on soymilk, reaching a cell number of 2×10⁹ cells/ml on 24 hr cultivation, at which time the medium had solidified and its pH had decreased to 4.0. Stachyose and raffinose in the medium were assimilated in preference to sucrose. A crude extract of B. breve 203 hydrolyzed the oligosaccharides in soymilk almost completely into their constituent monosaccharides. The α-D-galactosidase responsible for the first reaction in the degradation of the α-D-galactosyl oligosaccharides was isolated from a crude extract of the organism (500-fold purification, 2% yield) by means of ammonium sulfate-fractionation and column chromatographies on DEAE-cellulose, DEAE-cellulofine, Sepharose 6B, hydroxylapatite, Sephacryl S-300 and Phenyl-Sepharose 6B. The enzyme was a homo-octamer with a molecular weight of about 330, 000, and its isoelectric point was 3.7. It reacted optimally at pH 5.5 and hydrolyzed Stachyose (Km 8.6 mM), raffinose (Km 4.4 mM) and melibiose (Km 3.0 mM), with 50-60% of its reactivity toward p-nitrophenyl α-D-galactoside (Km 0.16mM). The reaction of the purified α-D-galactosidase with soymilk and guar gum was also investigated.

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A methionine-auxotrophic mutant (Met^-) of Aspergillus oryzae was transformed to prototrophy (Met⁺) with plasmid pKA5-1 carrying a 3.5Kbp genomic DNA fragment of A. oryzae through treatment of spheroplasts with polyethylene glycol 4000 and CaCl₂. The highest transformation frequency obtained was 32 transformants per μg DNA. We recovered the transforming plasmid from the Met⁺ transformant cell, showing that this plasmid was derived from the original plasmid, pKA5-1. The mitotic stability of the Met⁺ transformant was about 70% after growth without selective pressure; the transforming DNA was lost in the Met^- clone. These findings suggest that the transforming plasmid, pKA5-1, exists in the transformant cell as a self-replicating circular DNA.
The gene in the 3.5Kbp DNA fragment, which complements the methionine-auxotrophic mutation, can be used as a selectable marker to construct efficient plasmid vectors for A. oryzae.

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A slime material was isolated from axenic cells of the cyanobacterium, Microcystis aeruginosa K-3A, grown in a synthetic medium. Isolation and purification of the slime material were facilitated by the application of a mild mechanical force followed by specific coagulation with calcium ions. The slime material, of a high degree of purity, was isolated in yields of 7.2% as dry weight and 34.5% as fresh weight from whole cells. The slime gel could immobilize a large volume of water in the native state.
The slime material contained 66.9% (w/w) carbohydrate and 12.8% protein. Chemical analyses showed that the carbohydrate was a heteropolysaccharide containing galacturonic acid, rhamnose and xylose as the major constituents in addition to the sugars, fucose, arabinose, mannose, galactose and glucose. The slime material was insoluble in cold and hot water but soluble in 1 N NaOH. Multivalent metal cations and an acidic pH specifically coagulated the slime material, to form gel.

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The membrane-bound cytochromes c of an obligate methylotroph, Methylomonas sp. YK 1, and a KCN-resistant mutant, YK 56, were separated into two cytochrome c fractions, non-adsorbed and adsorbed fractions, on DEAE-cellulose column chromatography. The proportions of the non-adsorbed and adsorbed cytochromes c were 40 and 60%, respectively.
The membrane-bound cytochrome c of the mutant strain was purified by a procedure involving solubilization, and DEAE-cellulose, Cellulofme and Octyl-Sepharose column chromatographies. The Two purified membrane-bound cytochromes c had almost the same characteristics. Absorption peaks of the reduced forms of the two membrane-bound cytochromes c were seen at 551.5, 522.5, and 417.5nm at room temperature, and a shoulder on the β-band appeared at 530nm at low temperature. The molecular weight was calculated to be 10, 000 by high pressure liquid chromatography and the isoelectric point to be 4.1.

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Nine autifungal stress compounds were isolated and identified from the roots of adzuki bean (Vigna angularis) that had been treated with Cephalosporium gregatum type B, which is an avirulent strain of a pathogenic fungus causing brown stem rot disease on the host plant. These compounds were a novel isoflavanone dihydrowighteone, seven isoflavonoids.known as dalbergioidin, phaseol, 2'-hydroxygenistein, lupiwighteone, lupinalbin A, (3R)-(-)-vestitol, demethylvestitol, and one flavanone naringenin.

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Microorganisms that asymmetrically produce D-p-hydroxyphenylglycine (D-HPG) from DL-5-(p-hydroxyphenyl)hydantoin (DL-HPH), an intermediate in the chemical synthesis of DL-HPG, were screened from stock cultures and soil samples.
Of the 430 strains of bacteria, yeasts and actinomycetes obtained from our stock cultures, only two, Achromobacter delicatulus AJ-2446 and Achromobacter delicatulus AJ-2447, were capable of producing D-HPG from DL-HPH, but the yields were rather low. A bacterium with high productivity was isolated from a soil sample. It was classified as a bacterium belonging to the genus, Pseudomonas. In the presence of intact cells of Pseudomonas sp. AJ-11220 isolated from soil, which was selected as the best strain, D-HPG was produced from D-, L- and DL-HPH at a molar yield of more than 90%. This suggests that racemization and asymmetric hydrolysis occurred simultaneously in this reaction system.

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A bacterium isolated from soil, T-523, which hydrolyzes DL-5-indolylmethylhydantoin to L-tryptophan, was classified as a bacterium belonging to the genus, Flavobacterium. The prevention of tryptophan degradation by Flavobacterium sp. AJ-3912 (T-523) was investigated for improvement of the L-tryptophan production, because the L-tryptophan accumulated on enzymatic production from DL-5-indolylmethylhydantoin was partially degraded. L-Tryptophan production by Flavobacterium sp. AJ-3912 increased with the addition of agents that inhibit tryptophan oxygenase, such as hydroxylamine and phenylhydrazine, to the reaction mixture. In the presence of an appropriate concentration of hydroxylamine, the amount of L-tryptophan produced from L-5-indolylmethylhydantoin reached 8.8mg/ml, with a molar yield of 99% (in the absence of hydroxylamine, 7.1 mg/ml with a molar yield of 80%).
The L-tryptophan productivity was also improved with the use of mutants with a genetically blocked tryptophan degradation pathway. In the presence of intact cells of a representative mutant, AJ-3940, L-tryptophan was produced with a molar yield of 97%.

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Two hybrid plasmids bearing a mutant allele of the histidine operon of Serratia marcescens on a mini-F plasmid vector were constructed: one was plasmid pSS503 harboring the 4.7-kb EcoRl fragment bearing the initial part of the histidine operon and the other was plasmid pSH368 harboring the 12-kb EcoRI-BamHI fragment bearing the whole histidine operon. Both plasmids increased the activities of ATP-phosphoribosyltransferase (hisG product), histidinol dehydrogenase (hisD product) and histidinol phosphate phosphatase (hisB product) about two-fold, as compared with those observed with the plasmid-free host strain, a histidine-producing strain, L120, of Serratia marcescens. Both plasmids were considerably unstable in the histidine-producing strain, although they were completely stable in the wild-type strain. Strain L120 carrying either pSS503 or pSH 368 produced 42mg/ml or L-histidine; this productivity was approximately 50% more than that of plasmid-free strain L120.

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A cDNA expression library was constructed from rat liver poly(A)⁺ RNA by the vector primer and tailed linker methods using an Escherichia coli expression vector pKEN601 [K. Nakamura, Y. Iwasaki and T. Hattori, Gene, 44, 347 (1986)]. Immunological screening of this library with specific antibody against rat serum albumin identified a colony which carried a plasmid with a cDNA insert of 2.15 kilobases (kb). Restriction enzyme mapping and DNA sequencing analyses indicated that this cDNA clone carries a complete length rat serum albumin cDNA, and the 5'-terminus of the cDNA is in the potential capping site of the corresponding nuclear gene sequence.

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A coagulation test of soymilk-protein was carried out with various commercial proteinases originating from microorganisms, plants and animals. The soymilk-protein was coagulated by the following proteinases: Bacillus amyloliquefaciens, Bacillus subtilis, Bacillus polymyxa, Streptomyces griseus, Streptomyces caespitosus, Aspergillus oryzae, Aspergillus sojae, Endothia parasitica, Rhizopus sp., Mucor miehei, bromelain, papain and trypsin. However, such proteinases as Aspergillus saitoi, rennin and pepsin did not coagulate the protein. The coagulability of enzymes decreased as the pH of the soymilk was increased from 5.9 to 6.7. The optimum temperature for soymilk-clotting activity varied widely with the enzyme origin; for example, 55°C in the case of proteinases of Bacillus polymyxa and Rhizopus sp., 65°C in that of Aspergillus oryzae, Aspergillus sojae and trypsin, 75°C in that of Bacillus amyloliquefaciens, Streptomyces griseus, Streptomyces caespitosus and Endothia paracitica, and 85°C in that of Bacillus subtilis and Bacillus thermoproteolyticus. The coagulum made with the enzyme was separated into soymilk-curd and whey in a volume ratio of 1 to 1 by centrifugation at about 1600 × g. The moisture content of the curd was about 87%.

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Three water-soluble arsenic compounds were isolated from the brown alga, L. japonica, and their structures were elucidated by using ¹H- and ¹³C-NMR spectroscopy. All were arsenosugar compounds, which had the 5-deoxy-5-dimethylarsinoyl-ribofuranoside moiety in common. Two minor compounds had a glyceryl moiety in the molecules. The major fraction, which counted for 80% of the total arsenic compounds, was found to be a mixture of very similar compounds, possibly a diastereomeric pair. Both had the dihydroxypropane sulfonate moiety in their side chains.

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The raw starch-binding α-amylase of C. butyricum, an acidogenic anaerobe found in mesophilic methane sludge, was purified by chromatography on a column of Bio-Rex 70 after the enzyme had been liberated from potato starch granules. The molecular weight of the purified enzyme was determined to be 89, 000 by sodium dodecyl sulfate (SDS) disc electrophoresis. The iodine reaction completely disappeared at 9% hydrolysis of soluble starch by the enzyme, and the successive formation of maltooligosaccharides proceeded at pH 5.0 and 37°C. Decreases in the levels of maltopentaose and maltotetraose then took place as well as the formation of glucose, there being eventually almost 36% hydrolysis of the substrate.

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The sterilizing effect of supercritical carbon dioxide (SC-CO₂) is described as compared with gaseous CO₂(G-CO₂) and liquid CO₂(L-CO₂). Baker's yeast, Escherichia coli, Staphylococcus aureus and conidia'of Aspergillus niger were sterilized by treating with SC-CO₂ at 200 atm and 35°C when the water content of each microorganism was 70-90%. However, dry cells with a water content of 2-10% could not be sterilized under the same conditions. No sterilizing effect from SC-CO₂ on endospores of Bacillus subtilis and B. stearothermophilus was observed. G-CO₂ and L-CO₂ produced no sterilizing effect against both wet and dry baker's yeast cells, while wet E. coli cells were sterilized with G-CO₂. Although dry conidia of A. niger could not be sterilized with SC-CO₂ alone, the addition of ethanol or acetic acid to SC-CO₂ made it possible to sterilize these. Without any decrease in their enzymatic activities, E. coli and baker's yeast in a-amylase and lipase preparations were sterilized with SC-CO₂.

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The preparation of defatted mustard by extraction with supercritical carbon dioxide (SC-CO₂) is described. Oil was not extracted from native mustard seeds but was extracted from compressed mustard seeds with SC-CO₂at 300 atm and 40°C. When the extraction time and temperature were kept constant at 3hr and 40°C, 80-90% of the oil in the compressed mustard seeds could be extracted with SC-CO₂ at more than 300 atm. The solubility of the mustard seed oil in SC-CO₂ at 300 atm and 40°C was estimated to be about 0.48%. The synigrin content and myrosinase activity in the defatted mustard seeds with SC-CO₂ at 300 atm and 40°C for 3 hr were comparable to those in native seeds. Thus, the extraction with SC-CO₂ made it possible to prepare defatted mustard of high quality without decreasing the synigrin content and myrosinase activity.

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Purification of the precipitate obtained from juice oil of Citrus hassaku by chromatography afforded a main compound, whose structure was determined to be 7-geranyloxycoumarin, aurapten, on the basis of chemical and spectral evidence. This compound was isolated from Citrus hassaku for the first time. The antimicrobial activity of aurapten and several synthesized related coumarins against 5 bacteria and a fungus was investigated using the agar dilution method. Auraptenal exhibited the highest activity among them, at the concentration of 25 ppm, against all the microorganisms tested in this study.

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Glutamine synthetases [L-glutamate; ammonia ligase (ADP forming), EC 6.3.1.2] were purified, respectively, 570-, 220- and 80-fold with 12, 5 and 0.5% yields from cell-free extracts of Bifidobacterium bifidum a, B. breve 203 and B. pseudolongum a. The purification procedure consisted of cell disruption, ammonium sulfate fractionation and column chromatographies on DEAE-cellulose, Sepharose 6B and hydroxylapatite. The purified enzymes were judged to be homogeneous on polyacrylamide disc gel electrophoresis. They had similar molecular weights of about 500, 000. The optimum pH was 6.0-6.5 for their biosynthetic reactions with 30 mM Mg²⁺, and 6.5 for their γ-glutamylhydroxamate forming (transferring) reactions. The Km values for L-glutamate, ammonia and ATP in their biosynthetic reactions were, respectively, 18-25mM, 0.56-0.69mM and 1.5-2.0mMwith 30mM Mg²⁺ asacofactor. When 7.5 mM Mn²⁺ was substituted for 30mM Mg²⁺, the Km for L-glutamate decreased by 8.6-23-fold. The optimum pH for the biosynthetic reactions and the susceptibility of the enzymes to some metabolites also varied with the kind of divalent cation.added.

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Ozonized l-trifluoroacetyl-3-pyrroline (2a) and 3-sulfolene (6) were reduced with sodium cyanoborohydride (1) to afford the dialdehyde, which reacted in situ with the primary amines 3a-d in the presence of 1 to give the piperazines 4a-d (21-60%) and the dioxothiomorpholines 7a-d (26-76%). Reduction of 7a and 7c with diisobutylaluminum hydride yielded the thiomorpholines 8a and 8c, respectively. On the other hand, the 9-membered azacrown ethers 10 and 11 were obtained when N, N'-dibenzylethylenediamine (9) was employed. The dioxothiomorpholine derivatives 13 of amino acids were also prepared by the same treatment.

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We immobilized peptidylarginine deiminase, a Ca²⁺ -dependent protein-modifying enzyme which catalyzes the deimination of arginyl residues in protein, on formyl-Sepharose 4B by reductive amination. The immobilized enzyme was quite stable in the presence of reducing reagents and chelators such as DTT and EGTA. The immobilized enzyme was inactivated under the catalytic conditions in the absence of substrate. The inactive enzyme, however, was totally reactivated by replacement of Ca²⁺ by a mixture of reducing reagent and chelator in the equilibration buffer.
Our preceding paper described the specific modification of the functional arginine residue in soybean trypsin inhibitor (Kunitz) (STI) by peptidylarginine deiminase [H. Takahara, H. Okamoto, and K. Sugawara, J. Biol. Chem., 260, 8378 (1985)]. In this work, the rate of the modification of STI by the immobilized enzyme packed in a column was measured by continuous application of STI at constant temperature and flow rate. The extent of the modification of STI put on the column was linear to about 70% with the reciprocal of the flow rate. The effects of pH and calcium ion on the catalytic behavior of the immobilized enzyme were essentially the same as those of the soluble enzyme reported previously. The steady-state kinetic analyses of STI modification by the immobilized enzyme found that the Km and k_cat/Km values were 6.0-8.8 μM and 8.7×10⁴M^-1•s^-1 (37°C), respectively and the activation energy was 10.2-15.7 kcal/mol.

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We constructed deletion derivatives of pSVE-1, a plasmid containing the entire sporulation gene spoVE of Bacillus subtilis, and pSVESS, a plasmid carrying the spoVE85 mutation. Complementation analysis with these plasmids and analysis of gene products encoded in the cloned segment by the DNA-directed protein-synthesizing system showed that the spoVE gene product is a 32, 000 dalton protein.

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The insecticidal δ-endotoxin genes cry-1-1 and cry-1-2 derived from Bacillus thuringiensis var. kurstaki HD-1 were cloned, and their nucleotide sequences were determined. The nucleotide sequence of cry-1-1 was identical with the one reported by Schnepf et al. except for one base in the coding region. The coding regions of our two cloned toxin genes were not identical, but showed homology. More intensive variations in the sequences were observed in some regions, predominantly in the center of the coding region, 3'-terminal portion and 3'-flanking region. The differences in nucleotide sequences may have been mainly induced by base exchanges and deletions. Both translated products in E. coli were toxic to Bombyx mori larvae, but their insecticidal activities were considerably different.

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A cya mutant (HY1025) in which cya expression was completely inhibited was constructed by use of the reversed genetic method. HY1025 was mutagenized by transposon Tn10. Next, cAMP-requiring mutants were isolated in minimal medium containing glucose. In the mutants, the locus mutagenized by Tn10 was different from cya and crp, and was tentatively named cid. The property requiring cAMP was dependent on both cya and cid. Furthermore, mutants (cid:: Mud(Ap^r lac)) containing fusions of the lac gene to the cid gene were isolated. Among these strains, the expression of β-galactosidase was induced by cAMP. These experiments showed that Escherichia coli has cAMP-dependent growth regulation.

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Allosamidin, a product of Streptomyces sp. No 1713, inhibited Bombyx mori chitinase specifically in a competitive way with a Ki of about 0.1 μM. The effect of allosamidin on chitinases from Streptomyces griseus and Serratia marcescens was weaker, about 1/500 that on B. mori chitinase. Allosamidin did not inhibit yam chitinase, lysozymes of hen egg-white or human urine, or B. mori β-N-acetyl-D-glucosaminidase. The results suggest that allosamidin is a specific inhibitor of the insect chitinase.

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An emulsion was prepared by homogenizing soybean oil with an α_s1-casein solution. The α_s1-Blcasein adsorbed to the oil/water interface in the emulsion was digested with trypsin and then analyzed by reversed-phase high-performance liquid chromatography. Two peaks, T-1 and T-2E, due to the same fragment (¹⁹⁴Thr-Thr-Met-Pro-Leu-Trp) were found. Amino acid analysis showed that the ¹⁹⁶Met of T-l had been oxidized to methionine sulfoxide, and the NMR spectrum indicated that the ¹⁹⁶Met-Pro bond of T-1 had been subjected to cis-trans isomerization. The isomerization of the same peptide bond was also observed when this peptide fragment was oxidized by chloramine-T in solution, suggesting that cis-trans isomerization of ¹⁹⁷Pro was induced by ¹⁹⁶Met oxidation.

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Propylgallate, an antioxidant, inhibited the growth of Escherichia coli. The drug caused a decrease in phosphatidylglycerol (PG) and a corresponding increase in cardiolipin (CL) in E. coli, but did not affect phosphatidylethanolamine. When the drug was removed from the medium, rapid accumulation of PG occurred with a concomitant reduction of CL, although the phospholipid content did not change. E. coli phospholipids showed a two phase transition by measurement of differential scanning calorimetry. The drug lowered the transition temperatures and strongly interacted with the phopholipid species which showed the lower phase transition.

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Cucumisin [EC 3.4.21.25] was coupled to cyanogen bromide-activated Sepharose 4B. The specific activity of the immobilized cucumisin was 41% of that of the soluble cucumisin toward casein. The immobilized enzyme was more stable against alkaline inactivation or heat than the soluble enzyme. In using affinity chromatography on a column of the immobilized cucumisin-Sepharose, cucumisin inhibitor was not obtained from potent sources of proteinase inhibitors, such as pig kidney and liver, avian and turtle egg-whites, or soybeans.

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Botryococcus braunii strain Austin and strain Berkeley cultured under the same conditions contained 27.4g and 34.0g of lipids per 100g of dry alga, respectively. The lipids in the former strain were 25.5% hydrocarbons, 58.8% other nonpolar lipids, and 15.7% polar lipids, and those in the latter strain were 71.6%, 9.2%, and 19.2%, respectively. Distinct differences were also observed in the components of the nonpolar and polar lipids, especially in the latter, between the strains. The fatty acid composition of the nonpolar lipid fraction in Austin strain was unique, oleic acid being 81% of the total acids.

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The metabolic fate of the carbon skeleton of L-[U-¹⁴C]phenylalanine, tyrosine and aspartic acid was investigated in growing rats fed with diets containing different percentages of protein calories (0, 5, 10, 15 and 30 PC%) at 4100 kcal of metabolizable energy per kg of diet.
The incorporation of ¹⁴C into the body protein at 12hr after the injection of ¹⁴C-phenylalanine was more than 80% of the dose in the dietary groups of 0 and 5 PC%, and it decreased gradually at higher PC% levels. The pattern of incorporation of ¹⁴C-tyrosine into the body protein was similar to that of phenylalanine. The carbon skeleton of ¹⁴C-aspartic acid was extensively oxidized to expired carbon dioxide, and ¹⁴C incorporation into the body protein was markedly less. The pattern of expired ¹⁴CO₂ production from each ¹⁴C-amino acid was in inverse proportion to that of ¹⁴C incorporation into the body protein.
These results suggest that although tyrosine is not an essential amino acid for the growth of rats, the carbon skeleton of tyrosine is preferentially utilized for protein synthesis, especially in the protein depletion, and that the metabolic response of these amino acids to dietary protein changes at 10 to 15PC%, where the growth rate reached its approximate maximum.

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A NADH dehydrogenase was solubilized and partially purified from Pediococcus halophilus, which is capable of lowering the redox potential of the growth medium. The enzyme is specific for NADH. 2, 6-Dichlorophenolindophenol, ferricyanide, NET and especially various quinones can act as electron acceptors. The optimum pH for the activity was pH 6.0 and the optimum NaCl concentration was found to be 10-15% (w/v). The enzyme was inhibited by SH-reagents, p-chloromercuribenzoate and HgCl₂, but not by EDTA. None of the tested strains which were unable to lower the redox potential possessed the NADH dehydrogenase. A coincidental relationship was observed between the NADH dehydrogenase activities and the abilities to reduce the redox potential of several soy pediococcal strains.
It was observed that the addition of some quinones caused a noticeable increase in the browning rate of moromi juice in an early stage of soy sauce brewing (MJ). These results suggest that NADH dehydrogenase plays a substantial role in the depression of browning of MJ by rH-lowering soy pediococci.

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In order to make yeast cells secrete useful materials, an expression and secretion vector was constructed using the promoter and the signal sequence of yeast invertase coded by the SUC2 gene. When mouse amylase, after removal of its own signal sequence, was ligated with the secretion vector pSMF38T, amylase activity was secreted by the yeast Saccharomyces cerevisiae. The amount of the secreted enzyme was estimated to be 600μg/liters culture under the derepression conditions for the SUC2 promoter function.

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Plasma Factor XIII is a zymogen of plasma transglutaminase (EC 2.3.2.13), which is responsible for the intermolecular crosslinking of fibrin molecules during blood clotting. The factor is a tetramer (a₂b₂) comprising catalytic (a₂) and noncatalytic (b₂) subunits. By fusing mouse myeloma cells with spleen cells of a mouse immunized with Factor XIII protein that was partly purified from bovine plasma, we generated a hybridoma clone (A2) that synthesized a monoclonal antibody against bovine plasma Factor XIII. The subclass of IgG produced by clone A2 was IgG_2a. The monoclonal antibody was not cross-reactive with human placental Factor XIII or guinea pig liver transglutaminase. Experiments with a monoclonal-antibody immunoadsorbent column indicated that the monoclonal antibody recognized an epitope on the noncatalytic subunit, and that bovine plasma Factor XIII also dissociated into catalytic and noncatalytic subunits in the presence of a high concentration of Ca²⁺, as human plasma Factor XIII does. The catalytic subunits had catalytic properties similar to those of Factor XIII activated by thrombin. The immunoadsorbent column provided a one-step purification procedure that isolated the catalytic subunit of bovine plasma Factor XIII from plasma with a high yield. This simple method for isolation of the catalytic subunit will make it possible to use plasma transglutaminase in applied enzymology.

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Rabbit antibody to reduced carboxymethylated bovine β-lactoglobulin (SCM-β-Lg) was prepared and characterized in order to study the antigenic property of bovine β-lactoglobulin (β-Lg) which is a potential cause of an allergy to cow's milk.
On immunodiffusion analysis, a clear, single precipitin arc was produced between SCM-β-Lg and its antiserum, while a barely discernible line was observed between β-Lg and anti SCM-β-Lg antiserum. Analysis of the quantitative precipitation of SCM-β-Lg with β-Lg-absorbed antiserum to SCM-β-Lg indicated that there were at least four antigenic sites on SCM-β-Lg.
In a quantitative precipitin inhibition test and a two-step inhibition test involving an enzymelinked immunosorbent assay, anti SCM-β-Lg antibody reacted with peptides 1-65, 25-61, 25-107, 41-107, 62-107, 108-145, 125-145 and 146-162 from β-Lg, whereas peptides located in the N-terminal region, i.e., 1-7, 8-24 and 25-40, and peptide 108-124 showed little or no measurable affinity for antibody to SCM-β-Lg.
These results indicate that SCM-β-Lg has at least four antigenic sites, which are associated with regions 41-61, 62-107, 125-145 and 146-162 in the primary structure of β-Lg.

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The optical isomers often kinds of insecticidal 1, 3, 2-oxazaphospholidine 2-sulfides (OS) and two kinds of 1, 3, 2-benzodioxaphosphorin 2-sulfides (BS), including the commercial insecticide salithion, were synthesized in high optical purity by using two optically active aryl methyl phosphorochloridothionates (AMPC) as chiral two-step phosphorylating reagents. Their configurations were assigned according to the reaction mechanisms and supported by proton NMR information.

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For the defense mechanism against pathogenic bacteria in the digestive tracts of silkworm larvae reared on mulberry leaves, in vitro evidence of the formation of a true antibacterial substance was obtained. Caffeic acid (CA) derived from chlorogenic acid (ChA) was converted into caffeoquinone (CQ) by base-catalyzed oxidation in a buffer solution (pH 10.0). CQ was trapped as 6'-phenylsulfonylcaffeic acid (6'-sulfone) by the addition of benzenesulfinic acid (BSA).
The synergistic effects of amino compounds on the antibacterial activity of CQ are discussed in detail, and the probable reactions of CA with amino and thiol compounds in the alkaline solution are proposed.

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Factors affecting the development of the ice nucleation (IN) activity of Erwinia ananas IN-10 were examined, using the degree of supercooling (DS) as a parameter. An aqueous suspension of the bacterial cells or the outer membrane fraction showed two particular DS values, i.e., near 0°C and 3°C. The development of the DS of 0°C required two conditions: a high cell (or membrane) concentration and the presence of a water/glass interface in the system. Sugars inhibited the development of this type of supercooling. The IN activity was stable in the pH range of 5 to 10. On the basis of these data, a possible mechanism for the IN activity development was proposed. The application of the IN activity of the cells to the freeze-drying of high salt containing foods was attempted. It led to a shortening of their freezing times and efficient formation of powdered products.

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The title compounds were synthesized from starting materials of microbial origin by employing a Wittig reaction as the key step.

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