The Taka-amylase A (TAA) gene was cloned from the genomic library of A. oryzae using synthetic DNA oligomers as probes. The gene was located in a 3.7 Kbp EcoRI fragment. A. oryzae transformants containing a EcoRl fragment showed increased TAA activity, the increase being 2 to 5-fold. The complete nucleotide sequence of the gene was determined and it was found that the gene consisted of 2040 bp, with eight introns. The deduced amino acid sequence was compared with that reported by Toda et al., with the following findings. A presumed signal peptide consisting of twenty-one amino acids was found at the N-terminal. One insertion, one deletion and ten substitutions of amino acids were observed, which may be due to strain variation.

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B. subtilis 65 α-amylase (MW 68, 000) showed raw potato starch-digestibility and hydrolyzing ability toward low molecular weight substrates such as maltotriose (G3) γ-cyclodextrin (γCD) and p-nitrophenylmaltoside (PNP-G2). Kleistase α-amylase (MW 48, 200), α-amylase purified from B. subtilis, showed strong raw corn starch-digestibility, but it was deficient in raw potato starch-digestibility and low molecular weight substrate-hydrolyzing ability. Liquefying α-amylase (MW 45, 000; purified from B. subtilis), which hardly digested raw starches, could not hydrolyze low molecular weight substrates. Raw starch-digesting α-amylase of B. subtilis 65 was converted to a raw starch-nondigesting form through the action of pronase. But, the pronase-digested α-amylase retained the hydrolyzing ability toward low molecular weight substrates. It is suggested that the characteristic region liberated by pronase is essential for digestion of raw starch by the amylase.

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Some properties of phosphodiesterases I (EC 3.1.4.1) from the plasma membrane of bovine mammary gland (PM) and from bovine milk fat globule membrane (MFGM) were studied and compared, using mostly p-nitrophenylthymidine 5'-phosphate (5'-PNPpT). The optimum pH was found to be 9.5-9.6 inethanolamine-HCl buffer. The enzymes from both PM and MFGM hydrolyzed 5'-PNPpT, p-nitrophenyl phenylphosphonate, and bis(p-nitrophenyl) phosphate but not p-nitrophenylthymidine 3'-phosphate. The Km of the enzymes was 1.7 × 10^-3 M for PM and 1.6 × 10-3 M for MFGM using 5'-PNPpT. The activities of the enzymes from both membranes were inhibited by Mn, Zn, Co, Ni, and Cu ions and by EDTA, but unaffected by anions, and stimulated slightly by Mg and Ca ions. The properties of the enzyme of MFGM were very similar to those of the PM. The results suggest that the enzyme of MFGM is derived originally from that of PM, supporting the theory that MFGM is derived from the apical plasma membrane of the secretory cells.

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Leucyl t-RNA synthetase from a thermophilic bacterium, Bacillus stearothermophilus, effectively catalyzed the synthesis of p¹, p⁴-di(adenosine 5'-)tetraphosphate (Ap₄A), p¹, p⁵-di(adenosine 5'-)-pentaphosphate (Ap₅A) and adenosine 5'-tetraphosphate (p₄A). In particular, when the reaction was coupled with an ATP recycling system involving thermostable acetate kinase and adenylate kinase, Ap₄A and Ap₅A were produced selectively in high yields. This reaction is selective, gives high yields and does not require protection of the functional groups of nucleotides, and also it can be carried out in an aqueous solution. This method is superior to the conventional organic synthesis and provides a practical means of the synthesizing diadenosine polyphosphates (Ap_nA), biologically important compounds.

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Myosin rod fragments were prepared from both chicken leg and breast muscles to examine the reason for differences in the heat-induced gel strengths of these myosins at high ionic strength and low pH. The heat-induced gelation of the myosin rods was studied under the same conditions as those of intact myosin [Morita et al., Agric. Biol. Chem., 51, 2895 (1987)]. It was verified that unheated myosin rods showed similar differences in turbidity, viscosity, and filament length as intact myosin, and the heat-induced gel structures were compared. In summary, the results showed that the turbidity of breast myosin rods began to increase at pH 5.8 but that observed with leg myosin rods did not increase at that pH, although it was higher than that of breast myosin rods below pH 5.5. The viscosity of breast myosin rods increased as the pH decreased between pH 5.5 and pH 5.8, although that of leg rods decreased. At pH 5.7, leg and breast myosin rods assembled to form short filaments before heating. Both myosin rods formed longer filaments at pH 5.4, although breast rods tended to form longer ones. These results were approximately in agreement with those of intact myosin. Examination of the structure of the heat-induced gel of the leg myosin rods at pH 5.4 with scanning electron microscopy revealed a finer network structure (gel strength 3, 300 dyn/cm²) than that of breast myosin rods (2, 500 dyn/cm²) which were coarser and more aggregated than the former. These results indicate that the differences in filamentogenesis and heat-induced gelation of myosin rods from chicken leg and breast muscle myosins at high ionic strength and low pH may be related to those in thermogelation of each myosin.

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Haedoxan A, a new insecticidal sesquilignan, was isolated from the root of Hae-doku-sou, Phryma leptostachya L., and the structure was elucidated as a l-hydroxy-2-[(2, 6-dimethoxy-3, 4-methylenedioxyphenyl)oxy]-6-[6/-methoxy-2'-methoxymethyl-3/-(3, 4-methylenedioxyphenyl)-2/, 3'dihydro-r, 4'-benzodioxin-7'-yl]-3, 7-dioxabicyclo[3.3.0]octane on the basis of spectroscopic and chemical information involving syntheses of its partial structures. Its relative stereochemistry was revealed to be (1S^*, 2R^*, 5R^*, 6S^*, 2'R^*, 3'R^*) or (1S^*, 2R^*, 5R^*, 6S^*, 2'S^*, 3'S^*).

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Alkalophilic Bacillus No. A-59 produced 5'-nucleotidase (EC 3.1.3.5) extracellularly when Mn²⁺ was added to the growth medium. The enzyme formation was negligible in the medium without the addition of Mn²⁺ and the optimum Mn²⁺ concentration for the enzyme production was 10 mM. The 5'-nucleotidase was purified and its molecular weight was determined to be 78, 000 by gel filtration. The optimum pH for its activity was 9.0 - 9.5. The enzyme was stable in the pH range of 8.5 to 9.5, and up to 40°C. A substrate specificity study revealed that the enzyme hydrolyzed 5'-AMP strongly, several 5'-XMPs and ADP weakly, but not 3'-XMP, 2'-XMP, ATP or p-nitrophenyl phosphate. The Km value for 5'-AMP was 1.5 mM. The maximum enzyme activity was obtained without divalent cations. The enzyme was inhibited by borate and arsenite ions, but not by 2mM EDTA.

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Acidiphilium sp. 63 and 24R, which were isolated from strongly and weakly acidic environments, grew well on glycerol. Both glycerol kinase and glycerol 3-phosphate dehydrogenase (G3PDH) were induced during growth on glycerol. After centrifugation of the crude extracts at 100, 000 x g for 60 min, the G3PDH activity in strain 63 was found in the precipitate, on the other hand, 80 % of that in strain 24R was found in the supernatant. We solubilized the G3PDH from strains 63 and 24R with 0.1 % Brij 58, and both enzymes were purified to homogeneity. When a detergent was removed from these enzymes with cold aqueous 90% acetone, the activities were reduced to 11% and 28%, and were restored to about 55% of the original activities on addition of 0.1% Brij 58. By sonication with phospholipid, the 63-G3PDH activity was restored very well. Both purified enzymes have a molecular weight of 108, 000 and their coenzymes were FAD. These enzymes from strain 63 and 24R had a Km of 0.38 and 1.3 mM for DL-glycerol 3-phosphate and the optimal pHs of these enzymes were 7.0 and 8.8, respectively.

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The effects of the levels (10, 20, and 30%) of dietary proteins, soybean protein or casein, on various lipid parameters were examined in rats. The plasma and liver cholesterol (CHOL) level tended to decrease with an increasing dietary protein level, in particular when diets contained CHOL. The hypocholesterolemic effect of soybean protein was evident with CHOL-enriched diets. The fecal excretion of acidic but not neutral steroids increased with an increasing protein level and it was higher in rats fed soybean protein than in those fed casein. The ratio of arachidonate to linoleate in plasma and liver phosphatidylcholine tended to elevate accompanying with an increasing dietary protein level, although it was considerably higher in casein than in soybean protein diets. The results indicated that the hypocholesterolemic effect of soybean protein is influenced not only by the level but also by the presence or absence of dietary CHOL. In addition, the degree of the conversion of linoleate to arachidonate also depended on both the type and level of dietary protein.

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A fructooligosaccharide-producing β-fructoturanosidase was purified from cells of Aspergillus niger ATCC 20611. The molecular weight was 340, 000 by gel filtration. The optimum pH of the enzyme was 5.0-6.0 and the optimum temperature was 50-60°C. The enzyme was rendered inactive by 1 HIM Hg²⁺ and the Km value for sucrose was 0.29 M. The enzyme catalyzed an almost exclusively fructosyl transfer reaction in a 50% sucrose solution to produce a mixture of fructooligosaccharides and glucose, but both fructosyl transfer and hydrolytic action were observed in a 0.5 % solution. The β-fructofuranosidase showed a high regiospecificity to transfer the fructosyl moiety for the 1-OH group of terminal fructofuranosides.

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Sweet substances (sucrose, lactose, glucose, fructose, galactose, glycerin and aspartame), excepting Na saccharin, effectively interacted with a negatively-charged lipid membrane of dioleyl phosphate (DOPH). These sweet substances decreased the membrane resistance and depolarized the membrane potential. This response differed from those to bitter, sour and salty substances. Together with the result for transient response, it is suggested that sweet substances could penetrate the lipid membrane. Mono- and disaccharides exerted their effects at a concentration corresponding to the threshold value of taste sensation in vivo. Aspartame, which is about 100-fold sweeter than sucrose, was effective at one-hundredth of this concentration. In addition, the effect of sweet substances on a positively-charged lipid membrane was studied. Changes in the membrane electrical potential and resistance were observed by employing Na saccharin, which had no effect on the DOPH membrane.

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The effects of dietary protein on the ornithine decarboxylase (ODC) activity in rat liver were investigated, using whole egg protein, casein, gluten, and zein as the protein sources. In short-term feeding (fast-refed), ODC was induced in response to the nutritive value of dietary protein. In long-term feeding (2 weeks), however, ODC was induced by only the zein diet. At the same time, both the ornithine carbamoyltransferase (OCT) and ornithine-oxo-acid aminotransferase (OAT) activities were markedly decreased. OCT and OAT were specifically inhibited by leucine in vitro. ODC was also induced by an amino acid mixture simulating zein (A-l). Moreover, ODC was decreased by the diet (A-2) in which leucine was reduced from A-l, and was increased by the diet in which ornithine was added to A-2. These results suggest that the induction of ODC by feeding the zein diet for 2 weeks is due to the increased concentration of ornithine, arising mainly from the inhibition of OCT and OAT by leucine, which is contained in a large quantity in zein.

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As the result of extensive screening, we isolated 37 protein-hyperproducing bacteria. Their protein productivities were highly stimulated by polypepton, but not by yeast extract or meat extract. These bacteria produced 4.5-11.5g/l of cell bound and extracellular proteins under appropriate cultural conditions. Many of the selected bacteria showed characteristics of Bacillus brevis or species related to it as to cellular morphology and physiology. The bacteria which seemed to be B. brevis mostly accumulated one or two major high-molecular-weight protein species. Several strains were found to have excellent ability to produce proteins and showed no detectable extracellular protease activity. Such bacteria are expected to be potential hosts for the production of foreign proteins through recombinant DNA technology.

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Novel mycoloyl derivatives of monosaccharides related to trehalose-6, 6-dimycolate (TDM) were synthesized by coupling the natural mycolic acid that have been isolated from Mycobactreium tuberculosis Aoyama B with L-glucose, 2-deoxy-D-glucose, D-glucosamine, and 1, 5-anhydro-Dglucosaminitol.

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The pyruvic acid productivities of thiamine or lipoic acid auxotrophs derived from α-ketoglutaric acid-producing Enterobacter aerogenes SM-18 were determined using a washed cell reaction system. As a result, mutants showing high pyruvic acid productivities were more frequently found among lipoic acid auxotrophs, and one of them, strain L-12, was selected as the best producer. When this strain was shake-cultured in a medium containing 2 % glucose for 3 days, both pyruvic and α-ketoglutaric acids were produced in amounts of 4.7 and 1.6 g/1, respectively, with the limited lipoic acid concentration of 0.5μg/l, whereas only α-ketoglutaric acid was accumulated, in a yield of 5.5 g/1, with the sufficient vitamin concentration of 50 μg/1. The pyruvic acid production was confirmed to be due to a decrease in the activity of the pyruvate dehydrogenase complex caused by the lipoic acid deficiency.

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The N-glycosidic saccharide chains of S-glycoproteins associated with self-incompatibility in Brassica campestris were converted to the pyridylamino derivatives, and their structures were determined with physicochemical data and with the exoglycosidase treatment. These proved to be related to a saccharide chain of pineapple stem bromelain. The three S-glycoproteins, S₈, S₉ and S₁₂, carried the common oligosaccharides A and B. This indicates that the specificity of S-glycoproteins was not present in the saccharide chains themselves, but probably in the amino acid sequences.

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A β-glucosidase gene of Ruminococcus albus was introduced into Zymomonas mobilis NRRL B-14023, ATCC29191 and B69, on a newly constructed vector, a derivative of pZA22, by conjugal transfer with the helper plasmid pRK2013. Z. mobilis strains carrying this gene showed similar levels of intracellular β-glucosidase activity (per culture volume) to Escherichia coli carrying the same gene on pBR322. The stability of a hybrid plasmid carrying the β-glucosidase gene in Z. mobilis was examined through serial transfer tp antibiotic-free medium; 91-93 % after the first transfer and 60-85% after the fourth transfer of the Z. mobilis cells were β-glucosidase-producing ones in which the hybrid plasmid was retained.

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A sweet tasting peptide containing the L-lysine residue, N-acetyl-L-phenylalanyl-L-lysine, was synthesized from N-acetyl-L-phenylalanine ethyl ester (Ac-Phe-OEt) as donor and L-lysine esters as acceptor nucleophiles by an α-chymotrypsin catalyzed reaction. It was revealed by HPLC analysis that the reaction proceeded most satisfactorily at pH 9 within 3 min in a reaction system containing 100 mM Ac-Phe-OEt, equimolar esters of lysine and 10 JIM of the enzyme, where the product yield based on the donor concentration was 53 % for ethyl, 67 % for n-butyl and 31 % for benzyl esters. The highest reaction yield (75 %) was attained by using a double molar excess of lysine n-butyl ester. The present results suggest that α-chymotrypsin may become a useful tool for the synthesis of peptides containing basic amino acids.

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Chemical modification of histidine residues in castor bean hemagglutinin (CBH) with diethylpyrocarbonate (DEP) was studied with regard to saccharide binding. The analytical data clearly indicate that 6 out of 14 histidine residues in CBH are eventually modified with DEP at pH 6.1 in the absence of specific saccharides. Modification of histidine residues greatly decreased the cytoagglutination by CBH, and only 10 % of the residual activity was found in the derivative of CBH in which 2 histidine residues/mol were ethoxyformylated. Upon binding with galactose, the modified CBH containing 2 ethoxyformyl histidine/mol displayed an UV-difference spectrum with a maximum at 291 nm owing to the red shift of tryptophan, similar to native CBH, but its ability to bind galactose was one-fourth that of native CBH. On binding with galactopyranosides, the number of histidine residues eventually modified with DEP decreased by 2 per molecule, and the cytoagglutinating activity was retained. Hydroxylamine removed the ethoxyformyl groups from the inactive derivative of CBH which contained 6 ethoxyformyl histidine/mol, restoring the saccharide-binding ability. The results suggest that in the saccharide-binding site on each B-chain of CBH, there exists a histidine residue essential for interaction with a galactopyranosyl residue at the non-reducing end of saccharides.

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Expression of the STA1 gene, encoding an extracellular glucoamylase, is regulated positively by GAM1 or negatively by INH1 and heterozygosity at MAT (mating-type locus). From the analysis of diploid cells carrying mat mutations, we showed that different sets of mating-type genes were required for the repression of STA1 depending on both the copy number of STA1 and culture conditions. A multi-copy plasmid carrying STA1 relieved the MAT repression but did not affect glucoamylase production from INH1 or garni cells. RNA blot, SI mapping, and immunoprecipitation analyses revealed that GAM1 was required for the transcription of STA1 and that INH1 and heterozygosity at MAT exerted their functions at both transcriptional and post-transcriptional levels depending on culture conditions.

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Deletion analysis was used to identify sequences upstream of the STA1 gene of Sacchavomyces diastaticus that are required for its expression. Our analysis revealed that STA1 has at least three upstream activation sequences (UAS): UAS1 and UAS2-2 were required for full transcriptional activity, while deletions removing UAS2-1 were still transcribed but the transcripts failed to be translated. These sequences contained both A + T-rich and inverted repeat sequences that might serve as components of the upstream activation sites. We also showed that either deletion of a TATA homologue or insertion of palindromic DNA within the region between the TATA box and the mRNA start sites had no effect on the level of STA1 transcription but the transcripts failed to initiate properly.

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A bacterium, strain SD-74, which was isolated from soil under alkaline conditions, was found to abundantly produce acidic exolipids from n-alkanes. The strain proved to be alkali-resistant rather than alkalophilic and was identified as Rhodococcus erythropolis.
The acidic exolipids (15 g) were isolated from culture broth (11) containing n-hexadecane as the sole carbon source and were found to be composed of two new succinoyl trehalose lipids (STL-1 and STL-2). After purification, STL-1 showed mp 169 to 171°C and [α]^20D +92.3° (c = 0.6, CHCl₃/MeOH = 2:1), and STL-2 mp 161 to 163°C and [α]²⁰_D +75.0° (c = 0.6, CHCl3/MeOH = 2:1). On the basis of the results of chemical degradation and methylation, STL-1 and STL-2 were concluded to be 2, 3, 4, 2'-di-O-succinoyl-di-O-alkanoyl-α, α-trehalose and 2, 3, 4-mono-O-succinoyl-di-O-alkanoyl-α, α-trehalose, respectively.

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Factors affecting the extracellular production of succinoyl trehalose lipids by Rhodococcus erythropolis SD-74 were studied to optimize the culture conditions for the maximum production. Since the optimal pH for the production of the acidic exolipid was about 7, the addition of phosphate buffer (pH 7) of high concentrations (0.3 to 0.4 M) to shake culture media was essential for exolipid production. A high osmotic equivalent of culture broth (about 2% NaCl equivalent value) was favorable for exolipid production. Although K⁺ was superior to Na⁺, chlorides at higher concentrations were more inhibitory for exolipid production compared to sulfates or phosphates. Under the optimal conditions in a jar tormentor, the concentration of the exolipid in the culture broth reached about 40 g/l after 10 days.

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The flow behavior and dynamic viscoelasticity of deacetylated gellan gum solutions were measured with a rheogoniometer. The gellan gum showed Newtonian behavior with a range of concentration below 0.9%, but plastic flow behavior above 1.0% at 25°C. A gelation occurred in polysaccharide 6concentrations over 0.8% upon cooling, and a melting temperature was observed at 15 and 20°C at 0.8 and 1.0% concentrations, respectively. In the presence of CaCl₂ (6.8 HIM), the dynamic modulus of gellan gum showed a very high value at low temperature at the concentration of 0.2%, and increased with increasing temperature up to 80°C, which was estimated to be a melting temperature, then it decreased. Howevei>the gellan showed a little increase of dynamic modulus even at the concentration of 0.4% in the presence of NaCl (16.6 mM) or KC1 (13.5 mM). Gelation occurred for gellan gum in acid and alkaline range after reaching a pH 2.6 and 11.2 by addition of 100 mM HCl and Ca(OH)₂. The rheological characteristics of the gellan gum molecules might be essentially attributed to intra- and inter-molecular associations, possible structures of which have been proposed.

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Penicillium F-0543 (unidentified) converted deoxypodophyllotoxin (DPT), a major constituent (2.4%) of seeds of Hemandia ovigera L., to epipodophyllotoxin (EPT), which is the basic skeleton of the excellent anticancer agent, etoposide, in the high yield of 100%. Although the conversion rate varied, eight type cultures of Penicillium sp. tested also converted DPT to EPT. Three species of Aspergillus niger converted DPT to PT, but the yield were very low. Furthermore, it was found that many microbes examined converted DPT to a non-active substance, deoxypicropodophyllin (DPP), which is widely distributed in higher plants.

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S-Sulfoglutathione is reduced by reduced ferredoxin and ferredoxin dependent sulfite reductase (Fd-SiR) from the cyanobacterium Spimlina platensis. The Km value calculated from a Lineweaver-Burk plot of the data was 6.0 × 10^-5M. A plot of ferredoxin concentration versus reduction activity of S-sulfoglutathione (GSSO₃H) of Fd-SiR yielded a sigmoidal curve, giving a Hill coefficient (n) of 3.0. Antiserum against Fd-SiR strongly inhibits this reaction. In an experiment using a crude cell extract, the GSSO₃H reducing activity was only found at the site of Fd-SiR in gel filtration and immunoblotting.

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Seven novel fungitoxic sesquiterpenoids, chokols A, B, C, D, E, F and G, were isolated from stromata of Epichloe typhina on Phleum pratense. Their structures were determined by spectroscopic methods. The absolute configuration of chokol E was elucidated by its CD spectrum with Eu(fod)₃ and a chemical correlation with epicyclonerodiol oxide.

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The structure of malonylshisonin, a genuine pigment in purple Perilla leaves, was determined to be 3-O-(6-O-(E)-p-coumaryl-β-D-glucopyranosyl)-5-O-(6-O-malonyl-β-D-glucopyranosyl)-cyanidin.

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Both the enantiomers of (Z)-cis-9, 10-epoxy-6-heneicosene (2), a pheromone component of Phragmatobia fuliginosa L, were synthesized by employing the Sharpless asymmetric epoxidation as the key step.

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Cultured crown gall cells of Catharanthus roseus Don (Vinca rosea L.) was found to contain brassinosteroids. These were identified as brassinolide and castasterone by GC/MS. This is the first conclusive identification of endogenous brassinosteroids in cultured cells.

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We evaluated the expression of three yeast genes in Zygosaccharomyces rouxii using lacZ as a reporter gene; they were the gIyceraldehyde-3-phosphate dehydrogenase gene of Z. rouxii (GAP-Zr), that of S. cerevisiae (GAP-Sc) and the PHO5 gene of S. cerevisiae. The GAP-Sc promoter showed high expression in the Z. rouxii host as well as in the S. cerevisiae host. The GAP-Zr promoter showed a comparable level of expression as the GAP-Sc both in the S. cerevisiae host and the Z. rouxii host. The transcription initiation site of the GAP-Zr promoter in the heterologous host seems to be the same as that in the homologous host. The PHO5 promoter showed constitutive expression, as efficient as in the case of the GAP-Zr promoter, in the Z. rouxii host. All the promoters mentioned above can be used as sources of a high expression vector in the Z. rouxii host.

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New acyl coenzyme A: alcohol acyltransferase activity was found in the cell-free extract of Neurospora sp. ATCC 46892 which produces ethyl hexanoate abundantly in its culture broth. This enzyme catalyzed the esterification between ethanol and n-hexanoyl coenzyme A. It also acted on n-butyryl coenzyme A, but not on acetyl coenzyme A. It was detected mostly in the cytoplasm. The activity was accelerated by high concentrations of sodium chloride, and unsaturated fatty acid did not inhibit it. This enzyme played a major role in biosynthesis of ethyl esters which were formed with ethanol and higher acyl coenzyme As. This is the first report of an alcohol acyltransferase which does not have alcohol acetyltransferase activity.

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A hyphal extract was obtained by methanol extraction of a hyphal cake of Rhizoctonia solani culture. The crude hyphal extension inhibitor (HE-inhibitor), which only inhibits hyphal extension, i.e., without growth inhibition, was extracted with ethyl acetate, at pH 9.5, from the aqueous hyphal extract. The HE-inhibitor was further purified by silica gel column chromatography with a solvent mixture of benzene and acetone, and then separated into HE-inhibitors I and II. HE-inhibitor I, which highly inhibited the hyphal extension, with characteristic curling of the hyphal tips, was isolated as a colorless syrup, whereas HE-inhibitor II, with weak activity, was isolated as colorless needles: nip 187°C; C, 80.38, 79.14; H, 4.36, 4.96; N, 16.10, 15.94%. HE-inhibitors I and II exhibt no antibiotic activity against various fungi, yeasts and bacteria, but inhibit the hyphal extension of Rhizoctonia solani R-44 at 0.1μg/ml and 5.0μg/ml, respectively. Their inhibitory spectra resemble that of validamycin, though both inhibitors are less active than validamycin.

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