The structural changes in lutein, one of the major carotenoid pigments of wheat endosperm, during the storage of seeds were investigated. Wheat seeds were stored for up to 120 days at 30°C under a relative humidity of 75, 56, 32, or 8%. The wheat seeds were then milled, and carotenoid pigments were extracted from the flour with water-saturated butanol. The HPLC analysis revealed that the hydroxyl groups of lutein had been gradually esterified with fatty acids during storage. Esterification proceeded faster as the relative humidity was reduced. It seems that the rate of esterification was increased when the water generated by esterification evaporated from the seeds at low relative humidity. The amounts of free fatty acids, substrates for the esterification of lutein, in the flour increased during storage, the increase in free fatty acids proceeding faster as the relative humidity was increased. When the seeds were heated in an autoclave at 120°C for 20 min before storage, neither the esterification of lutein nor an increase in free fatty acids occurred. These results indicate that both reactions proceeded enzymatically. We speculate that the esterification of lutein occurred due to catalysis by lipase (triacylglycerol acylhydrolase), which produced free fatty acids from glycerides, or by other acylhydrolases which have similar kinetic properties to those of lipase.

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The rheological properties of 1-1.5% k-carrageenan gels mixed with galactomannan, i.e., locust bean gum, tara gum, and guar gum, in ratios of 7 : 3 and 1 : 1 were investigated by measuring the temperature dependence and the courses of dynamic viscoelasticity and static viscoelasticity. The addition of small amounts of locust bean gum and tara gum to k-carrageenan changed the rheological properties of the original to a firmer and more elastic gel. Measurements of the storage modulus (G') and loss modulus (G")showed that k-carrageenan formed the basic network structure of the gel, while locust bean gum and tara gum strengthened this network structure. k-Carrageenan showed a synergistic effect with locust bean gum and tara gum, but not with guar gum, which was caused by the difference of the constituent ratio of galactose to mannose in the three gums. Significant differences in the network structures of mixed gels of k-carrageenan and the three gums were apparent by observing with a scanning electron microscope.

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Sulfite dehydrogenase in the membrane fraction of Thiobacillus thiooxidans JCM7814 was solubilized with n-heptyl-β-D-thioglucoside, and then purified by DEAE-Sepharose and hydroxylapatite columns containing Triton X-100. The purified enzyme was electrophoretically homogeneous. The enzyme had an apparent molecular mass of 400kDa, and was composed of three subunits whose molecular masses were 74, 70, and 62 kDa. The purified enzyme was much more labile than the membrane-bound enzyme (membrane fraction). The optimal temperature of the membrane fraction was 25°C, while that of the purified enzyme was 20°C. The optimal pHs of both the enzymes were 7.5. The K_m's for sulfite of the membrane fraction and the purified enzyme were 4. 88 mM and 1.95 mM, respectively. The activities of both the enzymes were increased by adding Triton X-100 and inhibited by sulfhydryl-binding reagents.

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The digestion of raw starch by a glucoamylase (GA MU-H) from a mutant strain of Aspergillus awamori var. kawachi was closely correlated with mannoside chains O-linked to the Gp-I region (A⁴⁷⁰-V⁵¹⁴), but not sugar chains N-linked to catalytic GAI' domain of GA MU-H. The partial replacement of mannose residues by glucose residues led to a significant decrease raw starch digestion. By the substitution of D₂0 for H₂0 in the reaction mixture, the raw starch digestion of GA MU-H decreased to 80% of that at 30°C, although the rate of hydrolysis of soluble starch by and the ability to bind β-cyclodextrin of GA MU-H were unchanged. Glycerol, known as an antichaotropic reagent, decreased the raw starch digestion of GA MU-H significantly. However, it did not have any effect on the enzymatic activity for soluble starch when soluble starch was the substrate. The efficient digestion of raw starch with raw starch-digesting glucoamylase needed the mannoside chains O-linked to the Gp-I region, which were suggested to contribute to digestion of raw starch through the interaction with water.

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The prevention by acetic acid bacteria of coloration of foods was investigated by using a model system containing n-propanal and L-lysine. It was confirmed that acetic acid bacteria has a prevention against coloration caused by the amino-carbonyl reaction occurring between aldehydes and amino acids. A similar tendency was observed with mayonnaise to which intact cells of acetic acid bacteria were added. The prevention of acetic acid bacteria against coloration seems to depend on activity of a specific enzyme in the bacterial cells, a membrane-bound aldehyde dehydrogenase.

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A part of caseinphosphopeptides (CPP) formed during the digestion of casein in the small intestine of rats fed casein was not hydrolyzed in the digestive tract, but was excreted into the feces. Amino acid compositions of CPP fraction of feces for wk 1 and 2 were almost identical. The residual CPP in the feces expressed by the rate of bound phosphoserine in the CPP fraction of feces to bound phosphoserine ingested (phosphoserine-CPP/phosphoserine-ingested rate) in the ileum was the highest 4h after the start of feeding of casein but decreased significantly after 10h. No significant difference was observed in the rats of contents in jejunum, cecum, and colon between 4h and 10h after the start of feeding. No significant difference was observed in the phosphoserine-CPP/phosphoserine-ingested rate in contents of any part of the digestive tract between 50% casein and 50% CPP I (a commercial CPP product with nearly the same amino acid composition as that of casein) 4h and 10h after the start of feeding, except for the cecum 4h after the start of feeding. No significant difference in phosphoserine-CPP/phosphoserine-ingested rate was observed in the contents of any part of digestive tract between the groups fed 50% casein and 5% CPP III +45% soybean protein isolate (SPI) 4h or 10h after the start of feeding (CPP III is a commercial CPP product containing nearly 8times the concentration of phosphoserine as CPP I). The phosphoserine-CPP/phosphoserine-ingested rate of the 5% CPP I +45% SPI group was significantly higher in any part of digestive tract than those of 50% casein and 5% CPP III +45% SPI groups 4h after the start of feeding.

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Cycloinulooligosaccharide fructanotransferase (CFTase) that produces cyclofructan from inulin was purified about 69-fold from a culture broth of Bacillus circulans MCI-2554 by column chromatographies on DEAE-Toyopearl, QAE-Toyopearl, hydroxyapatite, and phenyl-Sepharose. The molecular mass of the enzyme was estimated to be 115 kDa by SDS-polyacrylamide gel electrophoresis and gel filtration, indicating a monomer structure. Maximal activity was observed at pH 7. 5 and 45°C. The enzyme was active from pH 5. 5 to pH 9. 5, and at temperatures up to 45°C. The enzyme activity was inhibited by Fe²⁺ and Cu²⁺. A part of the amino acid sequence was identical with that of β-fructofuranosidases of Zymomonas mobilis, carrot, Salmonella typhimurium, and mung bean.

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To establish the usefulness of amino acid based saltiness enhancers, soy sauce containing a basic amino acid, glycine ethyl ester hydrochloride, or taurine was prepared. The enhancer-added soy sauce produced the same level of saltiness as that of normal soy sauce, although it contained only 4.6°C NaCl. Taste quality of these samples was superior to that of low sodium chloride containing soy sauces that contain conventional saltiness enhancers, such as KCl, MgCl₂, MnCl₂, and others.

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The nucleotides of the xynB gene of Clostridium stercorarium F-9 were sequenced. The structural gene consists of an open reading frame of 1161 bp encoding a xylanase (XynB) in family F of 387 amino acids with a molecular weight of 44, 377. The molecular weight of the enzyme purified from a recombinant Escherichia coli was around 41, 000, smaller than the predicted value, on SDS-polyacrylamide gel electrophoresis due to the lack of 32 amino acids at the N-terminus. Intact XynB with a molecular weight of around 43, 000 was immunologically detected in the total cell proteins of a recombinant E. coli and C. stercorarium F-9. The purified XynB was active toward xylan, carboxymethylcellulose, p-nitrophenyl-β-D-xylopyranoside and p-nitrophenyl-β-D-cellobioside. The pH optimum was 7.0 and it was quite stable over the pH range of 5 to 12 at 4°C. This enzyme was optimally active at 80°C and retained about 50% of the original activity even after incubation at 100°C for 10 min.

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The thermal denaturation process of Clostridium stercorarium F-9 xylanase (XynB) was studied by monitoring remaining activity and recovered activity of the enzyme. At pH 5. 5, aggregation occurred rapidly after the thermal denaturation initiated. The aggregated protein could be dissolved in 8M urea solution, and the enzyme activity was recovered by diluting the urea. The extent of the recovered activity was gradually decreased with two phases as the reaction time of the thermal denaturation became longer. These results suggested the thermal denaturation process to be as follows : N→^^(k<SUB)1>D1&lrarr;^^(k<SUB)2>__(k<SUB)-2>D2→^^(k<SUB)3>D3 where N is the native state of the enzyme ; D1 is the denatured state of the enzyme that is formed rapidly after the reaction started and can be renatured by the urea treatment, and D2 and D3 are the denatured states of the enzyme that cannot be renatured even by the urea treatment. The rate constants were k₁>9. 2, k₂=0. 33, and k₂=0. 57, and k₃=0.13 (in min^-1 unit).

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Linoleic acid, ethyl eicosapentaenoate and ethyl docosahexaenoate were emulsified with cyclodextrins (CDs), dehydrated and then autoxidized. Autoxidation of the encapsulated sample proceeded over time and reached the level of the unoxidized fatty acid fraction, Y_∞, after which no further autoxidation occurred. The Y_∞ value increased with the increasing molar ratio of CD to fatty acid. Thermogravimetric (TG)analyses of these encapsulated samples suggest that some of the fatty acids were included in the CD-cavity. Furthermore, the fraction of fatty acids included into CD, which was determined by a TG analysis, correlated well with the Y_∞ value. It also seems that the fatty acids included into CD were highly resistant to autoxidation, whereas the remainder were rapidly oxidized at the same rate as that of the free fatty acids.

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The effects of rat bile-pancreatic juice (BPJ) on Fe²⁺ induced oxidation of soybean phosphatidylcholine (PC) was monitored to investigate the influence of this digestive juice on oxidative damage in the gastrointestinal tract. A large volume of BPJ (50% in the suspension of PC, v/v) suppressed the lipid peroxidation, but a smaller volume had the reverse effect. BPJ could decompose free fatty acid hydroperoxides (FFA-OOH) at a lower concentration (∼0.2mM) completely, although its phospholipase activity liberated FFA-OOH from PC hydroperoxides. Sodium deoxycholate enhanced the Fe²⁺ induced oxidation of PC in a concentration-dependent manner when PC was suspended in the buffer. Boiled BPJ suppressed Fe²⁺ induced and peroxyl radical initiated oxidation of sodium deoxycholate micelles of soybean PC up to ∼50% (v/v). It was strongly suggested that rat BPJ had a biphasic effect on Fe²⁺ induced oxidation of phospholipids depending on the enhancement by bile salts and the inhibition by antioxidant components with radical-scavenging activity and hydroperoxide-decomposing activity.

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Bovine mammary epithelial cells (BMEC) were isolated as acinous fragments from a mammary gland of a lactating cow. They grew well on plastic substratum, showed the characteristic cobblestone morphology of epithelial cells, and secreted α_s1-, β-, and k-caseins even when grown on plastic substratum. A plasmid containing the bacterial chloramphenicol acetyl transferase (CAT) gene was transfected to the isolated BMEC by calcium phosphate precipitation and electroporation methods. The transfection efficiency of BMEC by the calcium phosphate method was greatly improved by post-transfection osmotic shock with glycerol or polyethylene glycol. An about 700 bp DNA fragment containing 5'-flanking sequence of bovine α_s1-casein gene showed promoter activity in the transfected BMEC. The primary culture of BMEC might be useful for studies on regulation of bovine milk-protein gene expression.

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Acetobacter produces a gelatinous membrane composed of a cellulose network when grown in liquid culture under static conditions. The oxygen tension in the gaseous phase was found to have an effect on cellulose production and on the physical properties of the membrane. Cellulose production was higher at oxygen tensions of 10% and 15% than that under atmospheric conditions. In contrast, cell growth remained constant under a variety of oxygen tensions. Unexpectedly, the density of the cellulose network was found to be inversely proportional to the level of cellulose production by cells in the membrane through electron microscopic examination and other studies. It was concluded that this interesting phenomenon can be explained by our previously proposed model of BC network formation.

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The effects of milk gangliosides and their derivatives on the adhesion of enterotoxigenic and enteropathogenic Escherichia coli to Caco-2 cells, a human intestinal carcinoma cell line, were investigated. Human milk gangliosides inhibited the adhesion of enterotoxigenic E. coli to Caco-2 cells in the same proportion, regardless of the lactation stage, but bovine milk gangliosides were less effective. The most effective inhibitor was monosialoganglioside 1 (G_M1) ; the adhesion rate of enterotoxigenic E. coli in the presence of G_M1 was less than 20% of the positive control. The adhesion of E. coli was also depressed to 31.4% by monosialoganglioside 3(G_M3). However, the inhibitory effect of disialoganglioside 3(G_D3) was less than that of G_M3. G_D3 lactone, ceramide lactoside, and N-acetylneuraminic acid did not inhibit E. coli adhesion to Caco-2 cells. G_M3 also inhibited the adhesion of enteropathogenic E. coli to Caco-2 cells. Thus, these results suggest that G_M3 possibly behaves as a physiological component in the intestinal tract of infants to protect them against enteric infections.

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The complete nucleotide sequence of an open reading frame (ORF) preceding the Lactococcus lactis rpoD gene is reported. It was suggested that this ORF encodes Lactococcus lactis DNA primase and that the L. lactis rpoD operon consists of only two genes. Northern hybridization analysis showed that i) there are four mRNAs transcribing the rpoD gene (from upstream, M₁-M₄), ii) only the 3. 7-kb transcript M₁ includes the entire rpoD operon, iii) the shortest transcript M₄ exists at both logarithmic and stationary phases of growth while the other three transcripts appear only at logarithmic phase, and iv) no apparent induction at the transcriptional level but transient repression of M₁ was found when the growth temperature was shifted from 30°C to 42°C. 5'-ends of all four mRNAs were identified by primer extension analyses.

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Both the enantiomers of aseanostatin P5(sarcinic acid), an inhibitor of myeloperoxidase(MPO)release from human polymorphonuclear leukocytes(PMN), with high optical purity were synthesized by starting from (S)-2-methylbutanol and methyl (S)-3-hydroxy-2-methylpropanoate. They were converted to four diastereomers of aggreceride A, a platelet aggregation inhibitor.

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A novel fermentation process for simultaneous and high production of L-lysine and L-glutamic acid was established. This process was characterized by cultivating an L-lysine-producing strain with the cultivating methods for the production of L-glutamic acid, that is, cultivations with the addition of surface-active agents or penicillin. By these methods, without the addition of ammonium sulfate to culture medium, simultaneous and high production of L-lysine and L-glutamic acid with 1.3-1.4 fold higher productivity than that of the control was achieved. Various expected merits of this process from the viewpoint of industrial production of amino acids are discussed. It was suggested from the analysis of this newly-found fermentation process that the accumulation of L-glutamic acid could not be explained only the usual "leakage model" through the injury of cell membrane, but it would be necessary to consider the alterations in L-glutamic acid biosynthetic system.

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Goat IGF-I (gIGF-I) cDNA was cloned using the reverse transcriptase-polymerase chain reaction (RT-PCR). The cDNA, which was homologous to rat class 1 IGF-I cDNA, was 969bp long. From the open reading frame found in it, we predicted a 154 amino acid protein consisting of a 49 amino acid signal peptide, a 70 amino acid mature IGF-I peptide, and a 35 amino acid E domain (the COOH-terminal peptide). From the gIGF-I gene, we isolated and sequenced some segments containing four exons that encompassed the entire gIGF-I cDNA sequence. Goat liver RNA was analyzed by RT-PCR, and the nucleotides of the RT-PCR products were sequenced and checked with the nucleotide sequences of the segments from the gIGF-I gene. The gene had three leader exons (1W, 1, and 2, from upstream to downstream) and was transcribed into three kinds of mRNAs (classes 1W, 1, and 2). Another RNA species was detected by RT-PCR analysis of exon 1W. We sequenced it and found that in this transcript, the 3'-Portion of exon 1 was inserted between exons 1W and 3, resulting in class 1W-1del. mRNA. That is to say, the gIGF-I gene had three leader exons and four kinds of mature mRNA.

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3-Methylaspartase (3-methylaspartate ammonia-lyase, EC 4.3.1.2) from two facultative anaerobes from soil, Citrobacter sp. strain YG-0504 and Morganella morganii strain YG-0601, were purified and crystallized from their crude extracts. Both of the Citrobacter and Morganella enzymes appeared to be a dimer of subunits of M_r 40, 000 and 44, 000, respectively. The enzymes had similar enzymological properties : optimum pH for the deamination reaction of (2S, 3S)-3-methylaspartic acid, substrate specificity, inhibitor, divalent and monovalent cation requirement, and N-terminal amino acid sequence homology. However, some differences were detected in pH and temperature stability, optimum pH for the amination reaction of mesaconic acid, optimum temperature, specific activity, and stability during electrophoresis. Both enzymes had similar enzymological properties to the known 3-methylaspartase from an obligate anaerobic bacterium, Clostridium tetanomorphum H1, except kinetic constants and substrate specificities.

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The β-glucosidase of a phytopathogenic fungus, B. cinerea, was purified and characterized. The optimum pH and temperature for activity of the enzyme were 3.0 and 60°C. The β-glucosidase was stable up to 50°C and between pH 4.0-10.0. The M_r was 380, 000. The affinity of the enzyme for oligosaccharides tended to increase in parallel with their chain length.

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The decomposition rate of allyl isothiocyanate (AITC) in a low concentration range (below 1.6 mM) follows the first-order rate equation, and its degradation kinetics can be explained by the nucleophilic attack of water molecules and hydroxide ions on the AITC molecule. In aqueous solution, pH and temperature were important in the decomposition of AITC ; especially the temperature had a large influence on its rate.

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The unstable tert-butyl peroxide of a coelenterazine (Oplophorus luciferin) homologue was synthesized by a radical reaction. This compound is a model for a key intermediate in the bioluminescence of photoprotein aequorin.

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A microfluorometric method for the determination of cysteine was developed using 2, 6-dichloro-p-benzoquinone. 2, 6-Dichloro-p-benzo-quinone reacts quantitatively with cysteine in an acidic solution, and the reaction product is fluorescent. The assay was applied to vegetables and fruits by using TLC densitometry. The method is simple and rapid, and cysteine samples can be determined both qualitatively and quantitatively with comparatively high sensitivity (as little as 80pmol) by the reported procedure.

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The 1, 3-diethyl-2-thiobarbituric acid (DETBA) method for measuring lipid peroxidation could discriminate slight differences in garden peas with outward deterioration hardly recognizable with the naked eye. The increase in DETBA values during storage of the garden peas was closely related to the change in surface color and the decrease in both chlorophyll and ascorbic acid contents.

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A siderophore was isolated as a non-specific phytotoxic compound from a culture of Colletotrichum gloeosporioides isolated from infected blackberry. This siderophore was identified as ferricrocin by NMR, IR, MS, and CD spectra. The phytotoxic activities of ferricrocin and deferriferricrocin were compared.

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Usinhg γ-glutamyltranspeptidase, conditions for di- and tri-γ-glutamates synthesis were studied with glutamine and glutamic acid esters as substrates. The reactivity of amino acid esters was higher than for free ones. The efficient conditions were the combination of glutamine ethyl and glutamate diethyl esters with a molar ratio of 1/10 at pH 7-8.

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A major trypsin inhibitor (BTI-I) was purified from broccoli, Brassica oleracea, by conventional methods. BTI-I had a molecular weight of 8000 and an isoelectric point of 5.2. BTI-I inhibited bovine and porcine trypsins in an 1 : 1 (M/M) stoichiometry : the approxi-mate K_i's were 6x10^-11 M in both cases. The chemical modification suggested that BTI-I had an Arg-X bond as a trypsin reactive-site.

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The autolysis of tilapia m-calpain occurred even with very low free calcium at pH 5.5-7.5, and at 25°C or even 0°C. Substrates (casein mixture, α-casein, β-casein, fibrinogen, etc) affected the autolysis profile of calpain. Fragments from the degradation of α-casein seemed to inhibit the autolysis of the 80 kDa subunit.

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Single amino acid substitutions were introduced into the putative substrate-binding site of 3C proteinase (3C^pro) of coxsackievirus B3, a member of the picornavirus family. Mutations at either Thr142, His161, Gly164, Gly169, or Ala172 severely impaired or abolished the proteolytic activity except that a conservative Thr142to Ser mutant had detectable activity. These results, which have shown the participation of the 5 residues in 3C^pro activity, are consistent with the earlier predictions that these residues might be involved in substrate binding.

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Some properties of enacyloxin (ENX) oxidase from Frateuria sp. [Oyama et al., Biosci. Biotech. Biochem., 58, 1914-1917 (1994)] were studied. The enzyme catalyzed the oxidation of ENX IVa, ENX IIIa, and decarbamoyl ENX IVa, specifically. The optimum pH and temperature for the enzyme activity were pH 9. 0 and 60°C, respectively. It is suggested that the enzyme is a quinoprotein but its redox cofactor is different from pyrroloquinoline quinone.

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The gene (hbst) encoding the DNA binding protein HU from Bacillus stearothermophilus was cloned, with the Bacillus subtilis HU gene (hbsu) as a hybridization probe. The nucleotide sequence, which contains a ribosome binding site, a transcriptional termination signal, as well as the coding region, was analyzed by the dideoxy chain-termination method. The deduced amino acid sequence of an open reading frame was perfectly matched with that of B. stearothermophilus HU (BstHU) determined by the protein chemical methods [M. Kimura and K. S. Wilson, J. Biol. Chem., 258, 4007-4011 (1983)]. The gene, hbst, was overexposed using the expression vector pET-5a in Escherichia coli, and the recombinant HU protein (r-BstHU) was purified to be homogeneity by heparin-agarose column chromatography followed by ion-exchange column chromatography on S-Sepharose. The recombinant protein thus obtained had a circular dichroism spectrum identical to that of the authentic protein and bound to DNA to the same extent as the authentic protein.

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We examined the effects of hydrostatic pressure on the synthesis of Escherichia coli outer membrane proteins, particularly for the osmoregulated ImpC and OmpF porins. It was found that the expression of ompC and ompF was markedly reduced during the growth at high pressure, most likely at the transcriptional level. However, the signal transduction processes through the regulatory proteins, EnvZ and OmpR, was not influenced by the environmental pressure. It was also found that the expression of a presumed novel outer membrane protein, named OmpX, was affected by both the medium osmolarity and pressure in a manner independent of the function of EnvZ and OmpR.

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Tautomycetin was isolated as a regulator of secondary metabolite production for Penicillium urticae. It induced the simultaneous production of a yellow compound, named patulodin, and of patulolides against P. urticae P3, which does not produce such metabolites under the usual conditions. Tautomycin, a phosphatase inhibitor, also caused the same phenomenon.

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Two new rhodomycin metabolites, SS-288A and SS-288B, were specifically produced by a blocked mutant obtained from Streptomyces violaceus A262 and were respectively identified as 7, 10-di-(O-rhodosaminyl-deoxyfucosyl-deoxyfucosyl)-β-rhodomycinone and -β-isorhodomycinone.

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Two high-M_r mucin-like glycoproteins similar to each other, HMGP-A and C, have been discovered in human milk [Shimizu et al., Biochem. J., 233, 725 (1986)]. To characterize the properties of HMGP-A, specific antibody which is not reactive to HMGP-C was prepared by immunizing hens with HMGP-A. The HMGP-A-specific antibody (IgY) prepared by affinity-purification seems to be useful to distinguish HMGP-A-related antigens in milk and blood sera.

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CoASAc-independent phosphoenolpyruvate (PEP) carboxylase was purified from a serine-producing methylotroph, Hyphomi-crobium methylovorum GM2, and compared with those from other methylotrophs. The activity of thie enzyme was not affected by CoASAc, a well-known activator for enzymes from various hetero-trophs, NADH and ADP, effectors for PEP carboxylase from methylamine-grown Pseudomonas MA. This suggested that the H. methylovorum enzyme should be classified into the second group according to Utter and Kolenbrander (ref. 1) and different from that of Pseudomonas MA.

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The effects of α- and β-arbutin on the activity of tyrosinases from mushroom and mouse melanoma were examined. α-Arbutin was synthesized from hydroquinone and starch using glucoside synthetase (GSase). β-Arbutin inhibited both tyrosinase activities from mushroom and mouse melanoma. α-Arbutin inhibited only the tyrosinase from mouse melanoma, 10 times as strongly as β-arbutin. The IC₅₀ of α-arbutin was 0.48 mM and its inhibitory mechanism was speculated to be mixed type inhibition, while that of β-arbutin was noncompetitive.

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An expression plasmid for a thermostable chitinase gene from S. thermoviolaceus OPC-520 in E. coli was constructed. A cloned chitinase (Chi40) was purified from the periplasmic space of E. coli harboring the expression plasmid. The N-terminal sequence of Chi40 was 11 amino acids longer than that of chitinase from S. thermovilaceus OPC-520 (ST chitinase), however, a loss or addition of the amino acid residues did not affect the enzymatic properties. The mutations of Asp-145 and Glu-147 drastically decreased the specific activity of chitinase from the wild type, indicating that both amino acid residues are the best candidates for the essential catalytic residues of Chi40.

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The Saccharomyces cerevisiae gene YDR1/PDR5/STS1, which encodes a member of the ATP binding cassette (ABC) superfamily, is important for cross-resistance to apparently unrelated drugs. The expression of YDR1 is induced by various drugs and heat shock [Hirata et al., Curr. Genet., 26, 285-294 (1994)]. By deletion analysis of the 5'-noncoding region of the YDR1 gene, two drug responsive regions (-604 to -485 and -335 to -275) were identified with fluphenazine and cycloheximide. Three conserved palindrome sequences were found in these regions.

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By a sandwich enzyme-linked immunosorbent assay, a soybean major allergen, Gly m Bd 30K, in soybean products was measured. The allergen occurred at high concentrations in soy milk, tofu, kori-dofu, and yuba, but its content in kinako was small. No allergen was found in fermented foods such as miso, shoyu, and natto. The allergen was clearly shown to occur in meat balls, beef croquettes, and fried chicken that contained soybean protein isolate.

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Effects of pamamycins on [Ca²⁺]_i in Streptomyces alboniger were examined by microscopic fluorometry. Pamamycin-607, which has aerial mycelium-inducing activity, induced a transient increase in [Ca²⁺]_i dose-dependently, but the inactive pamamycin-649 had no effect on [Ca²⁺]_i.

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The effects of sulfatide, which is a specific sugar ligand for L-selectin (LECAM-1), on CCl₄-induced liver inflammation was studied in rats. Intramuscular pretreatment with sulfatide suppressed the levels of serum glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) that were increased by CCl₄ injection, but galactosylceramide, a desulfated form of sulfatide, did not. A light-microscopic analysis found that the extent and the severity of lesions of the liver cells induced by CCl₄ injection were significantly less in the rats treated with sulfatide. These results show that sulfatide suppresses the CCl₄-induced liver inflammation by inhibiting the attachment of L-selectin expressing lymphocytes to their native sugar legends.

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Pinguisone accumulated in cultured gametophytes of Aneura pinguis to a significantly high level. A biosynthetic study on the formation of pinguisone was carried out by feeding [2-¹³C]-acetate to the cultured gametophytes. Pinguisone was labeled at an adequate level to determine the labeling positions by a ¹³C-NMR analysis. The labeling pattern indicated two-methyl migration and C-C bond cleavage of the main chain in farnesyl diphosphate in the formation of pinguisone.

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S-Receptor kinase (SRK) is a kind of receptor protein kinase and has a receptor domain resembling S-locus glycoprotein (SLG). cDNAs encoding SRK⁸ and SRK¹² were isolated respectively from S⁸ and S¹² haplotypes of Brassica campestris. The SLG domains of SRKs were highly homologous to SLGs, suggesting that both SLG and SRK might bind the same legends in recognition of self-pollen.

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