A New Isoflavone with Antifungal Activity from Immature Fruits of Lupinus luteus

A new isoflavone having antifungal activity was isolated from immature fruits of Lupinus luteus (Leguminosae), and named luteone. The structure was shown to be 5,7,2′,4′-tetrahy-droxy-6-(3,3-dimethylallyl)-isoflavone by degradative and spectroscopic studies.     

The Influence of Measurement Parameters on the Specific Rotation of Amino Acids

The effects of solute and hydrochloric acid concentrations on optical rotation were studied using 20 naturally occuring amino acids.

There appeared to be no common factor among the amino acids as far as the inclination of optical rotation was concerned. Lutz-Jirgenson’s rule could be applied to few amino acids in the cationic form. Therefore, in the determination of the optical rotation, the concentration of the solute, nature of solvent and temperature must be rigorously controlled. The optical conditions of measurement and the specific rotation of 20 amino acids were recommended based on this work.     

Essential Role of Aspartokinase in L-Threonine Production by Escherichia coli W Mutants

We previously constructed an l-threonine-producing strain of E. coli W, KY8280, which is an Ile⁺ revertant of KY8279 which requires l-methionine, a,£-diaminopimelic acid and l-isoleucine [H. Kase et al., Agric. Biol. Chem., 35, 2089 (1971)]. From KY8280, another l-threonine-hyperproducing strain, KY8366, was obtained as an α-amino-β-hydroxy valeric acid (AHV, a threonine analog)-resistant mutant. Enzymatic analysis revealed that KY8280 constitutively expressed 8-fold higher l-threonine-sensitive aspartokinase I activity than KY8279. In addition, KY8366 constitutively expressed 13-fold higher l-lysine-sensitive aspartokinase III activity than KY8280. Such elevated levels of aspartokinases may contribute to the hyperproduction of l-threonine by these mutant strains. KY8366 produced 28 mg/ml of l-threonine in a culture medium fed with 12% glucose.     

Synthesis and Herbicidal Activity of 6-Phenyl-5-Propylamino-2-Pyrazinecarbonitriles and Related Compounds

6-Phenyl- and 5-phenyl-2-pyrazinecarbonitriles with or without a propylamino group at the 3-, 5- or 6-position of the pyrazine ring were prepared together with some related compounds from the corresponding 2,3-pyrazinedicarbonitriles. Their herbicidal activities against barnyardgrass and broadleaf weeds were examined in pot tests. The 6-phenyl-2-pyrazinecarbonitriles were relatively potent compared with the 5-phenyl derivatives. Moreover, the presence of a propylamino group at the 5-position of the 6-phenyl-2-pyrazinecarbonitriles was closely related to an increase in activity.     

Water-Soluble Glycoconjugates of Vegetables I. Isolation and Properties of Arabinogalactan-Proteins from Cabbage

We present a new method for isolating and purifying water-soluble arabinogalactan-proteins from cabbage and give their chemical properties. The water-soluble nondialyzable material from fresh cabbage was separated into three fractions (A-I, II, and III) by gel filtration on Sepharose CL-4B. A-I and A-II can be purified by HPLC. Borate is necessary to avoid formation of insoluble aggregates during isolation and purification. The molecular weights of A-I, II, and III were estimated to be 4.0×10⁵, 1.0×10⁵, and 1.0~4.0×10⁴, respectively. A-I and A-II are arabinogalactan-proteins with different carbohydrate/protein ratios: 5.5/1 for A-I and 11.4/1 for A-II. The carbohydrate moieties of A-I and A-II were both arabino-3,6-galactans having d-galactose/l-arabinose ratios of 1.9/1 and 1.5/1, respectively. The amino acid composition indicates an abundance of hydroxyproline, serine, threonine and alanine, the sum of which amounted to about 50% of the total amino acids. A-I contained 1.5 times more hydroxyproline (20%) than A-II (14%), while A-II contained higher proportions of serine, glycine, and alanine. A-III was not a glycoprotein but was a mixture of carbohydrate and polypeptides.     

Enzymatic fragmentation of carbohydrate moieties of radish arabinogalactan-protein and elucidation of the structures

We investigated the structures of L-arabino-galactooligosaccharides released from the sugar moieties of a radish arabinogalactan-protein (AGP) by the action of exo-β-(1→3)-galactanase. We detected a series of neutral β-(1→6)-linked galactooligosaccharides forming branches of one to up to at least 19 consecutive Gal groups, together with corresponding acidic derivatives terminating in 4-O-methyl-glucuronic acid (4-Me-GlcA) at the non-reducing end. Some oligosaccharide chains of degree of polymerization (dp) higher than 3 for neutral, and 4 for acidic oligomers were modified with L-Araf residues. The acidic tetrasaccharide 4-Me-β-GlcA-(1→6)[α-L-Araf-(1→3)]-β-Gal-(1→6)-Gal was detected as an abundant L-Araf-containing oligosaccharide among these neutral and acidic oligomers. A pentasaccharide containing an additional L-Araf group attached to the L-Ara in the tetrasaccharide through an α-(1→5)-linkage was also found. We observed L-arabino-galactooligosaccharides substituted with single or disaccharide L-Araf units at different Gal residues along these neutral and acidic β-(1→6)-galactooligosaccharide chains, indicating that these side chains are highly variable in length and substituted variously with L-Araf residues.     

Isolation and Structure of Gibberellin A18 from Immature Seeds of Lupinus luteus

A new gibberellin, tentatively called Lupinus gibberellin I, was isolated from young yellow lupin seeds. It has been shown to have structure (X), and now named gibberellin A₁₈.     

A Screening Procedure on the Inhibitors of Substrate-incorporation in Tumor Cells Methodological Survey and Its Evaluation

A comparative study of inhibition on the substrate-incorporation in several species of tumor cells has been achieved in combination with the antibiotics having different action mechanisms. It was thus revealed that a large part of the antitumor antibiotics so far examined showed a marked inhibitory response even at a low concentration. Particularly, the antibiotics whose action mechanism were established primarily on cell membrane were markedly sensitive. An apparent difference in the sensitivity was observed in some groups of antitumor antibiotics which act on nucleic acid synthesis. A methodological survey together with an evaluation of this procedure is discussed.     

Novel methods for nucleotide length control in double-stranded polyinosinic-polycytidylic acid production using uneven length components

ABSTRACT

Polyinosinic-polycytidylic acid (PIC), a double-stranded RNA that induces innate immunity in mammals, is a candidate immunopotentiator for pharmaceuticals. The potency and adverse effects of PIC are strongly correlated with the nucleotide length, and the inability to precisely control the length in PIC production limits its practical use. Length extension during the annealing process is the major factor underlying the lack of control, but tuning the annealing conditions is insufficient to resolve this issue. In this study, we developed a novel method to produce accurate nucleotide length PIC at an industrial scale. The length extension was significantly suppressed by the assembly of multiple short polyinosinic acid molecules with one long polycytidylic acid molecule. A newly developed PIC, uPIC100-400, demonstrated a reproducible length and better storage stability than that of corresponding evenly structured PIC. Human dsRNA receptors exhibited equivalent responsiveness to uPIC100-400 and the evenly structured PIC with the same length.     

Comprehensive phylogenetic analyses of the Ruppia maritima complex focusing on taxa from the Mediterranean

Recent molecular phylogenetic studies reported high diversity of Ruppia species in the Mediterranean. Multiple taxa, including apparent endemics, are known from that region, however, they have thus far not been exposed to phylogenetic analyses aimed at studying their relationships to taxa from other parts of the world. Here we present a comprehensive phylogenetic analyses of the R. maritima complex using data sets composed of DNA sequences of the plastid genome, the multi-copy nuclear ITS region, and the low-copy nuclear phyB gene with a primary focus on the Mediterranean representatives of the complex. As a result, a new lineage, “Drepanensis”, was identified as the seventh entity of the complex. This lineage is endemic to the Mediterranean. The accessions included in the former “Tetraploid” entity were reclassified into two entities: an Asia–Australia–Europe disjunct “Tetraploid_α” with a paternal “Diploid” origin, and a European “Tetraploid_γ” originating from a maternal “Drepanensis” lineage. Another entity, “Tetraploid_β”, is likely to have been originated as a result of chloroplast capture through backcrossing hybridization between paternal “Tetraploid_α” and maternal “Tetraploid_γ”. Additional discovery of multiple tetraploidizations as well as hybridization and chloroplast capture at the tetraploid level indicated that hybridization has been a significant factor in the diversification of Ruppia.