Alcohol-soluble proteins from Amaranthus seeds differ from prolamin fractions of cereals and plants. Albumins and globulins are the major fractions of Amaranthus. Peptide sequences of storage and membrane proteins from different cereals and plants were compared. Secondary structure of proteins was computerized by dot matrix and hydropathy analyses.

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Ice structure size in agar gel frozen by one-dimensional freezing was analyzed by mercury porosimetry. The mercury porosimetry for measuring ice structure size correlated well with the photographic results. The mean ice structure size was inversely proportional to the moving speed of the freezing front in accordance with the theory proposed by us before. Effects of additives, such as sucrose, sodium chloride, and urea, on the ice structure size were tested. With addition of these additives, the ice structure size increased as compared with the control with no additives. Addition of Triton X-100, however, substantially decreased the ice structure size, probably due to the reduction in the molecular diffusion rate of water at the ice-solution interface.

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We studied the effects of microbial products on glucose consumption and morphology of macrophages which were elicited with thioglycollate medium. Macromolecules such as lipopolysaccharide (LPS), tumor promoters, and respiratory inhibitors increased macrophage glucose consumption without inducing evident morphological changes. The assay system was used to screen for active substances in culture broth extracts from actinomycetes. Among them, aureothin increased glucose consumption of macrophages and inhibited respiration of a rat mitochondrial fraction. Concanamycin A induced morphological changes of macrophages into needle-like shapes but not of cloned cells including the macrophage-like cells J774.1. This compound changed fibrosarcoma L929 cells into round shapes without affecting the shape of a nontransformed fibroblast, BALB/3T3 cells. Antimycin and concanamycin A increased tumor-killing activity of macrophages when added during the effector phase. These results suggest that this assay system is simple and sufficiently reproducible and thus usable for screening for modulators of macrophage function among natural products.

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A novel extracellular pullulanase (PUL-E, pullulan 6-glucanohydrolase, EC 3.2.1.41) has been purified from the alkalophilic Bacillus sp. S-1. The purified enzyme had a molecular mass of about 140kDa on denaturated and natural conditions. The pI was 5.5. The pullulanase, when resolved by SDS-PAGE, was negative for Schiff staining, suggesting that the enzyme is not a glycoprotein. The N-terminal amino acid sequence of the enzyme was Phe-Leu-Asn-Met-Ser-(Trp-Phe). The enzyme displayed a temperature optimum of around 60°C and a pH optimum of around pH 9.0. The enzyme was stable to incubation from pH 4.0 to pH 11.0 at 4°C for 24 h. The presence of pullulan protected the enzyme from heat inactivation, the extent depending upon the substrate concentration. The activity of the enzyme was stimulated by Mn²⁺ ions. Ca²⁺ ions and EDTA did not inhibit the enzyme activity. The enzyme hydrolyzed the α-1, 6-linkages of amylopectin, glycogens, α, β-limited dextrin, and pullulan. The enzyme had an apparent K_m of 7.92 mg/ml for pullulan, a K_m of 1.63 mg/ml for amylopectin, and a K_m of 3.1mg/ml for α, β-limited dextrin, when measured at pH 9.0 and 50°C. The enzyme caused the complete hydrolysis of pullulan to maltotriose. The activity was not inhibited by α, β, or γ-cyclodextrins. The western blotting analysis with mouse anti-serum against PUL-E showed that PUL-E is produced as a single enzyme form during bacterial cultivation.

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The relative oxidative stability of six kinds of typical polyunsaturated fatty acids (PUFAs) was investigated in an aqueous solution (pH = 7.4 at 37°C) with Fe²⁺ -ascorbic acid as a catalyst. The highest stability was shown by docosahexaenoic acid (22 : 6n-3, DHA), followed by eicosapentaenoic (20 : 5n-3), arachidonic (20 : 4n-6), α-linolenic (18 : 3n-3), γ-linolenic (18 : 3n-6), and linoleic (18 : 2n-6, LA) acids, indicating that the stability increased with increasing degree of unsaturation. The significant difference found between α-linolenic and γ-linolenic acids also suggests the higher oxidative stability of n-3 PUFAs than of n-6 PUFAs in an aqueous solution. Moreover, when a mixture of DHA and LA was oxidized in an aqueous solution, the stability increased with increasing molar ratio of DHA to LA in the mixture. This characteristic oxidative stability of PUFAs in the aqueous phase is quite different from that in the neat phase, and can be explained by correlating with the conformation of PUFAs in the aqueous medium.

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Ultrastructure of the cortical cells of living bark, leaf buds, and flower buds of apple trees (Malus pumila Mill. var. domestica Schneid, cv. McIntosh) was studied. The ultrastructural changes in preexisting plastids, leading to formation of the plastid initials and subsequent intermediates in the formation of plastids, started in mid-January or early February and continued to occur through late March. The plastid initials of apple trees resemble that of poplar, and prolamellar bodies were abundant in the developing intermediates in the cells of leaf buds and flower buds. Association of the endoplasmic reticulum and vesicles with developing plastid initials suggests that the former two organelles may possibly participate in the development of the plastid initial. Thus, formation of plastids from plastid initials takes place seasonally at this stage.

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The replication region of the 2.77-kilobases (kb) plasmid pST1 from Streptococcus thermophilus No.29 was identified. Deletion derivatives of pST1 were introduced into plasmid-free S. thermophilus No.29 and examined for their ability to replicate autonomously. The nucleotide sequence had one open reading frame encoded for a 315 amino acid protein (Rep). Comparisons with proteins encoded by other Gram-positive bacterial plasmids strongly suggest that the deduced protein (RepS) encoded by pST1 has a replicative role. pST1 also contains a DNA sequence similar to the origin nick sequences of pLP1 or pLAB1000, which initiate plasmid replication at the plus origin. In a maxicell system, E. coli CSR603 carrying pSTUC4 produced a protein that was considered to correspond to the product of the RepS gene. These results strongly suggest that pST1 is replicated following a rolling-circle mechanism via single-stranded DNA intermediates.

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Ice fraction was measured for solutions containing glucose, sucrose, gelatin, and egg albumin at various concentrations at temperatures from 0 to -20°C. For glucose and sucrose solutions, the ice fraction was accurately measured from phase diagram, which could be interpreted by solution thermodynamics with two parameters. The ice fractions of these sample solutions increased with decreases in both temperature and concentration. Because of the limited applicability of the phase diagram method only to systems with low molecular weight materials, the DSC method was also used for ice fraction measurement. The DSC method, corrected for temperature-dependent latent heat of ice and corrected with Pham's equation, provided a good approximation for ice fractions with general applicability. The DSC method was used to measure the ice fractions of gelatin and egg albumin gels as a function of solute concentration. The freezing point and bound water of gelatin and egg albumin gels were described as a function of concentration. Effects of the differences in molecular structure on ice fraction were analyzed for various carbohydrate solutions at the same concentration. The ice fraction proved to be strongly dependent on the colligative properties of the solution with nonideal behavior.

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Cα-dehydrogenase catalyzes the oxidation of arylglycerol-β-aryl ether at the Cα-position, and therefore this process produces the specific substrate for β-etherase, which cleaves β-ary ethers (Cα carbonyl type). Here we isolated the Cα-dehydrogenase gene (ligD) and sequenced its nucleotides. This gene contains an open reading frame of 915bp and the deduced amino acid sequence had a homology with the ribitol dehydrogenase family. ligD is about 1 kbp upstream of the β-etherase gene (ligE).

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A novel moderately thermophilic iron-oxidizing bacterium was isolated from a coal dump in Iizuka City, Japan, and designated strain TI-1. Strain TI-1 was a Gram negative, non-spore-forming, and rod-shaped bacterium, which had a optimum temperature and pH for growth at 48°C and 2.2, respectively. The mean G + C content of the DNA was 56.2mol%. Strain TI-1 required yeast extract for growth and did not have the ability to fix carbon dioxide as a carbon source, indicating that the strain is not chemolithoautotroph. When grown on Fe²⁺ (1.7%)-yeast extract medium, Fe²⁺ was oxidized concomitantly with cell growth. The optimum pH and temperature for Fe²⁺ oxidation by washed intact cells of TI-1 were 2.8 and 50°C, respectively. The properties of strain TI-1 shown above, such as the G + C mol content of the DNA, the requirement of yeast extract for growth, and the inability to fix carbon dioxide, suggest that strain TI-1 belongs to a new type of mederately thermophilic, acidophilic iron-oxidizing bacterium.

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The molecular conformation of (1→3)-α-D-glucan tribenzoate (TBG) was studied by X-ray diffraction measurements coupled with a conformational analysis. Although the fiber pattern obtained was of very low crystallinity, the presence of a meridional reflection at the 5th layer line indicated that the TBG molecule took a five-fold helical conformation with a 19.63Å fiber repeat. A conformational analysis on the five-fold helix, which was done by calculating van der Waals' repulsion energy between non-bonded atoms comprising the TBG chain, suggested that the most preferable energy-based conformation was -5/1, a left-handed five-fold helix.

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The glycosidation of (+)catechin, which has five hydroxyl groups with cyclodextrin glucanotransferase (CGTase, EC 2.4.1.19) and soluble starch has been studied. One of the transfer products was purified and its structure was determined to be (+)catechin 3'-O-α-D-glucopyranoside. This glucoside noncompetitively inhibited the activity of tyrosinase from mushroom, IC₅₀ being 5.8 mM, but didn't inhibit that from mouse melanoma. In contrast, arbutin (hydroquinone-O-β-D-glucopyranoside) inhibited both tyrosinases.

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The adsorption isotherms for CO₂ to several polysaccharides were measured in a pressure range between 0 and 29.4 MPa by the gravimetric method. The adsorption of CO₂ to two kinds of starches (potato and corn) and to dextrin increased linearly with increasing pressure to reach a maximum, and then decreased sharply to constant level at higher pressure. These adsorption characteristics are similar to those of proteins reported previously. On the other hand, the adsorption of CO₂ to cellulose showed a high level at the beginning of the increase in pressure, without any significant change in the sub-critical pressure region, and then fell to the minimum before reaching a constant level at higher pressures. These adsorption characteristics of cellulose could be related to its micropore structure. The pressure at which the maximum adsorption occurred (P_max) was located on the P-T line of the CO₂ phase diagram where (∂p/∂P)_T was a maximum, this result being different from the Menon correlation of P_max = P_c( T/ T_c)² proposed for adsorption to macroporous adsorbents.

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The systemic immune response against orally administered antigens is suppressed (oral tolerance), and this has been postulated to avoid excess immunity against dietary constituents which are present in large amounts in the gastrointestinal tract. Taking into consideration that such orally administered protein antigens are subjected to enzymatic degradation in the gastrointestinal tract, we examined whether an enzymatic digest of milk proteins could induce oral tolerance. A tryptic digest of casein, containing mainly fragments smaller than 6000 Da, was fed to mice as a constituent of their diet. Mice fed with the casein-digest diet responded poorly to subsequent immunization with casein, indicating that oral tolerance to casein was induced in these animals. The results suggest the presence of immunosuppressive fragment(s) in the casein digest, which may be of use for preventing milk allergy.

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Effects of twelve flavonoids and five catechins as well as gallic acid on two kinds of glutathione-related enzymes were investigated. Glutathione S-transferase (EC 2.5.1.18) activity was measured by S-2, 4-dinitrophenyl glutathione formation from 1-chloro-2, 4-dinitrobenzene and reduced glutathione. Glutathione reductase (EC 1.6.4.2) activity was followed by NADPH dehydrogenation. Fisetin and myricetin were potent inhibitors of glutathione S-transferase, while kaempferol, quercetin, baicalein, and quercitrin were medium inhibitors. Epicatechin gallate and epigallocatechin gallate also showed medium inhibition. Kinetic analyses indicated that fisetin was a mixed type inhibitor of glutathione S-transferase with respect to both substrates, while myricetin was a competitive inhibitor of the same enzyme with both substrates. Fisetin and myricetin were noncompetive inhibitors of glutathione reductase with both NADPH and oxidized glutathione. The inhibition patterns of GT and GR as well as the results of kinetic analyses indicated a possibility that inhibitory flavonoids might have some influence on the glutathione recognition sites of the two enzymes.

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A unique β-fructofuranosidase was purified from the extract of Bifidobacterium adolescentis G1 by anion-exchange, hydrophobic, and gel filtration chromatographies, and preparative electrophoresis. The molecular mass was 74kDa by SDS-PAGE, and the isoelectric point was pH 4.5. The enzyme was a monomeric protein. The pH optimum was at 6.1. The enzyme was stable at pH from 6.5 to 10.0, and up to 45°C. The neutral sugar content was 1.2%. The enzyme hydrolyzed 1-kestose faster than sucrose or inulin. The hydrolytic activity was strongly inhibited by Cu²⁺, Ag⁺, Hg⁺, and p-chloromercuribenzoic acid. The K_m (mM) and k_o (s^-1) were : 1-kestose, 1.1 and 231 ; sucrose, 11 and 59.0 ; inulin, 8.0 and 149, respectively. From the kinetic results, β-fructofuranosidase from B. adolescentis G1 was concluded to have a high affinity for 1-kestose, thus differing from invertases and exo-inulinases in substrate specificity.

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Carboxypeptidase Y (CPY; EC 3.4.16.1) is the yeast vacuolar protease. To have CPY secreted and to increase its secretion level, we tried to express the prepro-CPY gene under the control of the inducible GAL10 promoter or constitutive ENO1 promoter on a multicopy plasmid. In the strains KK4, PEP4, and A2-1-1A, carrying the CPY expression plasmid, active CPY was not detected in the culture broth although the CPY activity was greatly increased inside the cells. In contrast, when we used a strain that contained the ssl1 (super-secretion of lysozyme) mutation, a large amount of active CPY (about 10-50 mg/liter) was detected in the culture broth. The ssl1 mutants secreted active CPY when the CPY level was increased by expressing it under the control of a strong promoter on a multicopy plasmid, while the endogenous expression of chromosomal CPY gene in the same ssl1 mutant caused a deficiency in the processing of pro-CPY to mature CPY.

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A chitinase gene (chiA) from Streptomyces lividans was characterized and its nucleotides sequenced. Although the deduced amino acid sequence of chitinase A1 did not show any similarity to those of other Streptomyces chitinases that has been sequenced, the C-terminal part, containing both a putative catalytic domain and type-III-like repeating units, showed a similarity (36%) to that of chitinase D from Bacillus circulans. A site of initiation of transcription was found approximately 51 bp upstream from the GTG initiation codon. The promoter region of the chiA gene was subcloned on a 178-bp fragment into the promoter-probe vector pIJ486, resulting in the chitin stimulated expression of the neomycin resistance gene. One of the deleted subclones, which contained a 114-bp sequence upstream from the translation start codon, retained both chitin stimulated production and glucose repression. Chitin stimulated production was lost in an other deleted mutant containing the 104-bp upstream sequence.

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Allosamidin (1) was converted to demethylallosamidin (2) and didemethylallosamidin (3) by a reaction with methylamine and ammonia, respectively. In the same way, a series of N-monoalkyl derivatives was prepared from 1 and 2. A variety of 6- and 6"-O-acyl derivatives of 1 was also prepared by chemically selective acylation. The inhibitory activity of each of these derivatives on chitinases originating from insects and fungi showed that a monomethylaminooxazoline or dimethylaminooxazoline structure was important for strong activity, and that the 6"-O-acyl derivatives of 1 each retained relatively high activity.

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A protein disulfide isomerase (PDI) was purified to homogeneity from the thermophilic fungus Humicola insolens by a rapid three-step procedure, anion-exchange chromatography, concanavalin A-affinity chromatography, and reverse phase high performance liquid chromatography. Forty-oneμg of PDI was obtained from 100g of wet mycelium. Concanavalin A-Sepharose chromatography is available for purification of the fungal PDI, indicating that the enzyme is also glycosylated like the yeast PDI. The fungal PDI exists as a dimer (2 x 60 kDa), has a pI of 3.5, and is fairly heat-stable. The amino acid composition of the PDI is similar to those of yeast and bovine liver PDI, and the high content of acidic amino acid residues agrees with the lower acidic pI.

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A system of multiple xylanase enzymes was detected in the culture supernatant of Aeromonas caviae W-61. Among the detected xylanases, two β-1, 4-xylanases (1, 4-β-D-xylan xylanohydrolases, EC 3.2.1.8), designated xylanases 2 and 3, have been purified to homogeneity, by using ultrafiltration, ammonium sulfate precipitation, DEAE-Toyopearl 650M, CM-Sephadex C-50, and high-pressure liquid chromatographies. Endoxylanase 2 was a basic protein of 41 kDa, and endoxylanase 3 was an acidic protein of 58 kDa. The two xylanases had different pH and temperature optima, as well as thermal stabilities. The two purified enzymes had no activity on β-1, 3-xylan, cellulose, carboxymethyl cellulose, or water-soluble starch. Various xylo-oligosaccharides such as xylotriose, xylotetraose, xylopentaose, xylohexaose, and higher oligosaccharides were formed, and only a small amount of xylobiose was detected as the hydrolysis products of oat spelt xylan by endoxylanase 2. Endoxylanase 3 released higher xylo-oligosaccharides as main products with very small amounts of xylotetraose and xylopentaose.

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The fungitoxic sesquiterpene (±)-chokolic acid A (1) was synthesized stereoselectively by starting from 2-methoxycarbonyl-(3-isopropenyl)cyclopentanone (2) in a 9% overall yield from 10 steps.

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A restriction endonuclease, Aor13HI, an isoschizomer of BspMII, was purified to homogeneity from cell extracts of Acidiphilium organovorum strain 13H. The enzyme has a molecular mass of 60, 000 daltons and consists of two subunits identical in molecular mass of 30, 000 daltons. Aor13HI endonuclease, like BspMII, recognizes the palindromic six-base sequence 5'-TCCGGA-3', and cleaves between the T and C to produce a four-base 5' extension. Aor13HI is not inhibited by dam-dependent methylation. The isoelectric point of the enzyme is 5.7. Aor13HI activity was maximum at pH 7.5, 100 mM KCl, 7.5-10 mM MgCl₂, and 55°C. The enzyme was stable up to 60°C. The N-terminal amino acid sequence (30 residues) of Aor13HI did not show any similarity with the sequence of other restriction endonucleases reported.

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The purpose of the present study was to determine whether the regulation of urea synthesis was mediated through the supply of nitrogen by amino acid-catabolizing enzymes and whether the concentration of acetylCoA would control the N-acetylglutamate concentration when the thyroid status was manipulated. Experiments were conducted on three groups of rats, each being given 6-propyl-2-thiouracil (PTU, thyroid inhibitor) without a triiodothyronine (T₃) treatment, or PTU + T₃, or neither PTU nor T₃ (control), respectively. The urinary excretion of urea, the liver concentration of N-acetylglutamate, and the hepatic activities of serine dehydratase, threonine dehydratase, alanine transaminase (GPT) and aspartate transaminase (GOT) in rats given PTU + T₃ were significantly lower than those in rats given PTU alone. The activity of glutamate dehydrogenase, and the concentrations of free amino acids and acetylCoA in the liver of the PTU + T₃-treated group were significantly higher than those in the group treated with PTU alone. These results suggest that the higher activity of amino acid-catabolizing enzymes in the hypothyroid (with PTU alone) rats is likely to stimulate urea synthesis.

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Stable and potent fibrinolytic enzymes (six homogeneous proteins) were purified to homogeneity from extracts of the lyophilized powder of an earthworm, Lumbricus rubellus. The molecular weight of each enzyme estimated by SDS-polyacrylamide gel electrophoresis was different from those by gel filtration chromatography in the six purified proteins. The exact molecular weight of each enzyme (F-III-2, F-III-1, F-II, F-I-2, F-I-1, and F-I-0) measured by ionspray MS analysis was 29, 662, 29, 667, 24, 664, 24, 220, 24, 196, and 23, 013, respectively. The isoelectric point (pI) of each enzyme was 3.40, 3.60, 4.20, 4.00, 4.30, and 4.85, respectively. The enzymes were single polypeptide chains. They had a very strong fibrinolytic activity and the maximum reactivity for chromogenic substrates from pH 9-11. The enzymes, acidic proteins that had abundant asparagine and aspartic acid, and low lysine in their amino acid composition, did not contain component sugars. The enzymes were stable at from pH 1-11 and up to 60°C. Studies on substrate specificity and inhibition indicated that these enzymes were alkaline trypsin-like serine proteases. N-Terminal amino acid sequences of the enzymes had local similarities to those of trypsin-like enzymes such as elastase and coagulation factor IX. From the results of amino acid sequence, amino acid composition analyses and immunological analyses, it was suggested that these six enzyme proteins were derived as isozyme(s) from at least four different genes.

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The IME2 gene product (Ime2) is required for entry into meiosis and sporulation in S. cerevisiae. It has been predicted to be composed of two domains, an amino-terminal domain with homology to protein kinases and a carboxy-terminal acidic domain. The Ime2 was identified in extracts of meiotic cells carrying multi- but not low-copy IME2 in immunoblot analysis using an Ime2-specific antibody. Immune complexes were found to phosphorylate Ime2 and several exogenous proteins. Low-copy plasmids expressing truncated Ime2 proteins that lack part of or the entire carboxy-terminal domain enabled cells to undergo sporulation even under a certain repressive nutritional condition. These cells contained increased levels of protein kinase activity compared with control cells. These results suggest that the amino-terminal domain has a protein kinase activity and that the acidic tail is not essential for either the kinase activity or sporulation but serves in a negative role. An Ime2-beta-galactosidase fusion was shown by immunofluorescence microscopy to be localized predominantly to the nucleus, suggesting a nuclear function of Ime2.

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Two Ca²⁺-dependent lectins were purified from the sea cucumber Stichopus japonicus by affinity chromatography on lactosyl-Sepharose 4B and ion-exchange chromatography on Q-Sepharose. Their molecular masses were estimated to be 13 kDa (SJL-I) and 15 kDa (SJL-II) on SDS-PAGE. SJL-I agglutinated rabbit erythrocytes as well as human A, B, and O-type erythrocytes, but SJL-II agglutinated only rabbit erythrocytes. Hemagglutination by SJL-I was competitively inhibited by N-acetyl-D-galactosamine and galactose-containing carbohydrates. On the other hand, only lactose, melibiose, and raffinose gave weak inhibition of hemagglutination by SJL-II, suggesting that SJL-II may have high specificity for particular complex carbohydrate(s) on the surface of rabbit erythrocytes. SJL-II was activated at ten times lower Ca²⁺ concentration than SJL-I. Both lectins lost activity in acidic pH, while SJL-I appeared more stable down to pH 4.5.

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The purified casein kinase II (CK II) from Arabidopsis thaliana phosphorylates wheat elongation factor 1β (EF-1β), but not elongation factor 1β' (EF-1β'), which lacks a serine residue in the conserved phosphorylation site. Both EF-1β and β' subunits, with similar functions, seem to undergo different regulation despite the partial amino acid sequence of EF-1β being similar to that of EF-1β'.

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Four angiotensin I-converting enzyme (EC 3.4.15.1) (ACE) inhibitory peptides C105, C107, C111, and C112 were isolated from bonito bowels. C111 was obtained from liver, while the others were from intestine. Their amino acids were sequenced as Ser-Val-Ala-Lys-Leu-Glu-Lys for C105, Ala-Leu-Pro-His-Ala for C107, Gly-Val-Tyr-Pro-His-Lys for C111, and Ile-Arg-Pro-Val-Gln for C112. Their ACE inhibition activities were measured for synthetic peptides. The IC₅₀ of these peptides were estimated to be 82, 79, 1.6, and 1.4μM, respectively. Carboxyl-terminal amino acid(s) were considered to be essential for their expression of ACE inhibition for C105, C107, and C111, while the amino terminal tripeptide Ile-Arg-Pro of C112 was presumed to inhibit ACE after the removal of a dipeptide from C112 with ACE digestion. Presumed original proteins of these peptides are discussed.

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^13C-NMR analysis of hot water extracts of samples during Pu-erh tea processing showed that carbohydrates and amino acids as well as catechins were digested during the microbial fermentation process and the main constituents of the made-tea were caffeine, gallic acid, and 2-0-β-L-arabinopyranosyl-myo-inositol. Volatile components analysis by GC and GC-MS showed abundant production of various methoxybenzene derivatives. Three strains of basidiomycete (Basidiomycetes spp. ) isolated from Pu-erh tea were confirmed to autonomously produce 1, 2-dimethoxy-4-methyl and 1, 2, 3-trimethoxy-5-methylbenzenes.

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We developed three new assay methods : an antialgal test using the diatoms, Nitzschia closterium and Naviculla sp.; a growth-inhibition assay against invertebrate larvae of Musculista senhousia; and an assessment of the residual amount of tested samples on conventional submerged assay plates used for screening antifouling substances. A combination of these assay procedures with the antimicrobial assay previously reported resulted in establishing a laboratory-maching, more reliable and time-saving assay system for antifouling substances.

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In connection with mutagen formation during food processing, furfural derivatives formed in the amino-carbonyl reaction between amino acids and sugars were measured by HPLC. At lower pH, the formation of 5-(hydroxymethyl)-furfural (HMF) in the browning reaction mixtures was increased and the browning intensity was decreased, while at higher pH, the former was decreased and the latter increased.

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Four geometric isomers of (11E)4, 6, 11-hexadecatrienal were prepared, and their pheromone activity towards male eri-silk moths was evaluated. The EAG activity of each isomer was determined by the EAG-GLC method in order of increasing activity to be (4Z, 6E, 11E)- and (4E, 6E, 11E)->(4E, 6Z, 11E)->(4Z, 6Z, 11E)-hexadecatrienal.

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We previously isolated a Serratia marcescens O5 : H1 Z-54 strain which produces a new reddish-violet pigment, a peptide-ferropyrimine complex. This study showed that polymyxin B enhances the formation of the pigment about threefold. This occurs because polymyxin B in the medium causes the formation of an iron-polymyxin B complex which imposes a low iron stress on the bacteria and, in turn, enhances pigment production. This shows that polymyxin B is both a membrane-disrupting and ionophoric antibiotic.

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A variety of substituted 3-indolepropionic acids and related compounds were synthesized and their antibacterial activities were examined against Pseudomonas solanacearum. In most cases, substitution in the indole ring greatly reduced the antibacterial activity, but some compounds substituted at the 4 position could effectively suppress bacterial growth at a concentration higher than 25 μg/ml.

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The optically resolved (±)-dihydrophaseic acid (DPA) was achieved by using a commercially available chiral HPLC column. PA and DPA, which were isolated after feeding (±)-(RS)-[²H₆]-ABA to avocado fruits, were analyzed by the chiral HPLC method to examine the stereoselectivity of the oxygenase. Small peaks of the unnatural enantiomer could be observed in each case. The results show convincingly that (-)-(R)-ABA was converted to PA and DPA, although the extent of this conversion is very small in comparison with the conversion of (+)-(S)-ABA.

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We constructed a cloning vector for use in the acidophilic heterotroph Acidiphilium facilis. The vector pAH101 (8.8kb) was constructed from a 6.1 kb restriction fragment of the Acidiphilium plasmid pAH1 and a pUC19 carrying a β-lactamase gene. The antibiotic resistance gene was efficiently expressed in A. facilis. Several factors which influenced the transformation efficiency were optimized, resulting in a transformation efficiency of up to 3×10³ transformants per μg of plasmid DNA at a field strength of 10 kV/cm with a 7.0 ms pulse.

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The blocked-N-terminal structure of hog kidney aldose 1-epimerase (mutarotase, EC 5.1.3.3) was determined to be Ac-Val-Ser-Val-Thr-Arg-Ser-Val-Phe-Gly-Asp··· by a coupling of conventional methods (enzymatic digestion, amino acid analysis, and Edman sequencing) and tandem mass spectrometry. The side-chain fragmentations observed in the high-energy product ion spectra gave unambiguous sequence information about the arginine-containing N-terminal structure.

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A comparison between germfree (GF) and gnotobiotic (GB) mice, inoculated with Bacteroides vulgatus, Eubacterium aerofaciens, Bifidobacterium longum, Enterococcus faecalis, Escherichia coli, and Clostridium perfringens, revealed that the GB mice suffered no deleterious effect on the apparent absorption ratios of Ca and P, and showed a higher apparent absorption ratio of Mg.

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Azole compounds inhibited both hydroxylation catalyzed by cytochrome P-450_sca and the growth of Streptomyces carbophilus. The growth inhibition could be overcome by inducing cytochrome P-450_sca production in the cells. These results suggest that cytochrome P-450_sca has an intrinsic substrate as well as xenobiotics. Such a P-450 that has both substrates seems to be unique among the prokaryotic P-450 enzymes.

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A glycoside was isolated from yeast extract and identified as ethyl-β-N-acetylglucosaminide.

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Gentisate 1, 2-dioxygenase, which participates in salicylate and m-hydroxybenzoate metabolism, was purified from cell-free extracts of Rhodococcus erythropolis S-1, a Gram-positive bacterium. The purified enzyme gave a single band on native PAGE and SDS-PAGE. The molecular mass of the enzyme was estimated to be 328kDa. The structure of the enzyme appears to be an octamer of identical subunits. The enzyme from this bacterium was similar in general enzymatic properties to a gentisate 1, 2-dioxygenase from a Gram-negative bacterium except for molecular mass and structure.

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The GAM1, GAM2, and GAM3 genes encode global regulators for transcription in the yeast Saccharomyces cerevisiae. We report here that GAM1 and GAM3 are required for both meiosis and transcriptional activation of meiosis-inducing genes, IME1 and IME2, and that GAM2 is not essential for meiosis but regulates transcription of IME1 and IME2 in positive and negative manners, respectively.

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The time-course for crystalline forms of calcium phosphates was investigated by the X-ray method in the absence and presence of citrate, a typical inhibitor of calcium phosphate formation. Dicalcium phosphate dihydrate (DCPD) was observed as a precursor without citrate, while DCPD was not observed in the presence of citrate, suggesting that citrate lowered the supersaturation degree of DCPD.

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We have constructed a YAC library containing over 5000 clones of tomato (Lycopersicon esculentum Mill. cv. VFNT) DNA with an average insert size of 320kb, which were equivalent to two haploid genomes. The tomato used here has four disease resistance traits. Therefore the library constructed should be useful for isolating genes of such traits by map-based cloning.

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We clarified the evolutionary position of Candida maltosa, an n-alkane-assimilating yeast, by sequencing the nucleotides of the small-subunit ribosomal RNA gene. Phylogenetic analyses showed the close evolutionary relationships of C. maltosa with C tropicalis, C. viswanathii, C. albicans, C. parapsilosis, and C. guilliermondii, forming a sub-group within this genus.

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The 1509 bp cryptic plasmid, pPF1, from Phormidium foveolarum, a strain of filamentous cyanobacteria of the LPP group, was completely sequenced. The pPF1 nucleotide sequence had 97.8% overall similarity with that of a small plasmid from Plectonema boryanum. The structural organization of pPF1 and vector construction are discussed.

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