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Two kinds of oligosaccharides, N-acetylraffinosamine (RafNAc) and N-acetylplanteosamine (PlaNAc), were synthesized from N-acetylsucrosamine and melibiose using the transgalactosylation activity of Aspergillus niger α-galactosidase. RafNAc and PlaNAc are novel trisaccharides in which d-glucopyranose residues in raffinose (Raf) and planteose are replaced with N-acetyl-d-glucosamine. These trisaccharides were more stable in acidic solution than Raf. RafNAc was hydrolyzed more rapidly than Raf by α-galactosidase of green coffee bean. In contrast, RafNAc was not hydrolyzed by Saccharomyces cerevisiae invertase, although Raf was hydrolyzed well by this enzyme. These results indicate that the physicochemical properties and steric structure of RafNAc differ considerably from those of Raf. Two kinds of novel trisaccharides were synthesized from N-acetylsucrosamine and melibiose, using transgalactosylation action of Aspergillus niger α-galactosidase.

The WaterLOGSY type experiment with 19F detection was applied to observe the interaction between a fluorinated compound and a macromolecule. The proposed experiment, which was developed based on the 19F{1H} saturation transfer difference experiment, was carried out using the conventional spectrometer equipped with a single high band amplifier and a H/F/C-double tuned probe. The selective 19F detection is advantageous in screening the fluorinated compounds, considering that 19F is a sensitive nucleus in NMR spectroscopy. The effective approach to discriminate binding of the fluorinated compounds to proteins with 19F detection was demonstrated using the complex of diflunisal and human serum albumin.

Diphenylarsinic acid (DPAA) and phenylarsonic acid (PAA), which were degradation products of organoarsenic chemical warfare agents used as sternutatory gas, were detected in the well water at Kamisu, Ibaraki Prefecture, Japan. The standard material of DPAA was synthesized with aqueous arsenic acid and phenylhydrazine in order to determine organic arsenic compounds in well water. The DPAA showed a protonated ion at m/z 263 [M + H]+ and a loss of H2O ion at m/z 245 [M + H − H2O]+ from protonated ion by the electrospray ionization time-of-flight mass spectrometry. The quantitative analysis of DPAA and PAA was performed by high-performance liquid chromatography inductively coupled plasma mass spectrometry and the system worked well for limpid liquid samples such as well water. Copyright © 2005 John Wiley & Sons, Ltd.

N-methyl-pyridinium formate, a novel component of coffee extracts, inhibited the multiplication of both DNA and RNA viruses. In the presence of the compound, the progeny viral yields of both herpes simplex virus type 1 (HSV-1) and poliovirus in HEp-2 cells and those of influenza virus type A in MDCK cells decreased with increasing concentrations of the compound, although the degree of viral sensitivity to this compound differed. In addition, none of these viruses were directly inactivated by the compound at the concentrations tested. Characterization of the mode of action of this compound against HSV-1 multiplication revealed that it inhibits the viral growth primarily at the initial step of virus multiplication, i.e., within 2 h after the onset of multiplication, although the virus multiplication was affected by the compound throughout the multiplication cycle. In addition, this compound showed a significant cytotoxic effect, although the observed antiviral effect was unlikely to be attributed to the cytotoxic effect.

Urinary excretion of hydroxylysine diglycoside (GGH) or monoglycoside (GH) is known to be a reliable indicator of metabolic status of bone collagen. Although some preparation methods of the standard GGH or GH from different species have been reported, this study demonstrated that the preparation of the GGH or GH from the human urine was more suitable for the analyses of these glycosides. GGH and GH were prepared in two ways : one from the normal human urine and the other from the alkaline hydrolyzate of marine sponge. The adequacy for their use as the standard substances was evaluated by proton NMR and HPLC. The glycosides obtained from the human urine were confirmed to be normal forms. As for the glycosides obtained from marine sponge, it was demonstrated that the glycosides were diastereoisomers. The urinary levels of GGH and GH of the inhabitants in Cd-polluted area were compared with the values obtained from non-polluted subjects. The measurements of GGH and GH were performed by using the glycosides prepared from the normal human urine as the standard substanses. As the results, the urinary GGH or GH levels of the subjects in the Cd-polluted area had wider distribution ranges than those of controls, although there was no significant difference between Cd-polluted subjects and controls.

A new tracer technique, in which a 13C-labeled compound as a biological tracer and 13C nuclear magnetic resonance (NMR) as an analytical tool are used, is proposed. In order to verify the applicability of the method to clinical chemistry. [1-13C]benzoic acid was administered and [1'-13C]hippuric acid excreted in the urine was quantitated by NMR, by using [1-13C]hippuric acid as an internal standard.

The structure of a new monomeric peptidoglycan-related compound with hypotensive and diuretic activities, cymbidine A (1) isolated from the orchid Cymbidium goeringii, was elucidated mainly by spectroscopic analysis. The structure of 1 was shown to involve four amino acids (D-alanin, meso-diaminopimelic acid, D-gultamic acid, and L-valine) and two amino sugars (N-acetylglucosamine and 1,6-anhydro-N-acetylmuramic acid). The sequence of the amino acids and amino sugars was determined by the analysis of 2D NMR data. The absolute stereochemistries of the three amino acids (D-Ala, D-Glu and L-Val) were determined by the modified Marfey's method, and the (6S,10R) configurations of meso-diaminopimelic acid in 1 were indicated on the basis of the CD analysis. The absolute stereochemistry of 1,6-anhydro-N-acetylmuramic acid was also determined by CD data.

Indium-mediated coupling reactions of δ-oxygenated allyl halide derivatives 1 with aldehydes in aqueous media proceeded at the y-position to give diol derivatives 2. Compound 1 is equivalent to an allylic carbanion 4 with a neighboring oxygen functional group generated in aqueous media.

Pi in the medium relieved the toxicity of arsenate against cellular growth of Chlamydomonas reinhardtii. To investigate the relationship between intracellular P contents and arsenate resistance, we determined the intracellular P contents of arsenate-sensitive and arsenate-resistant mutants, which had been generated by random insertional mutagenesis. All 13 arsenate-resistant mutants showed higher P contents than the parent strain, while arsenate-sensitive mutants with high P contents were not found. In one of the arsenate-resistant mutants, AR3, the intracellular P content was about twice that in the wild type during growth in the absence of arsenate. Arsenate incorporation in AR3 was suppressed within 10 min after the addition of 1 mM arsenate, while Pi incorporation continued even after arsenate uptake ceased. Whereas the P content of the wild type decreased to half in the presence of 0.5 mM arsenate, almost the same degree (about 50%) of decrease was observed in AR3 cells grown in the presence of as much as 3 mM arsenate. AR3, in which PTB1, a homolog of a Pi transporter gene, had been disrupted, exhibited a higher activity of a high-affinity Pi transporter, suggesting that it may be due to a compensatory transport activity. These data suggest that the intracellular level of P is one of the important factors of arsenate resistance.

Treatment of 1-diethylphosphonyl- or 1-phenylsulfonyl-2-(iodomethyl)cyclopropane-1-carboxylate with Et(3)B leads to an unsymmetrical allylated active methine radical species that gives functionalized cyclopentane derivatives with high stereoselectivity through iodine atom transfer [3 + 2] cycloaddition reaction with alkenes.

It was confirmed that the flexible arm region of HU alpha forms an antiparallel beta-sheet and that all of the residues of phenylalanines, together with some of leucines and/or valines, form a hydrophobic core within the dimer of HU alpha. HU alpha protein alone is thermally labile and melts at 38 degrees C, but it becomes remarkably stabilized and melts at 59 degrees C in the presence of DNA. Several resonances from both HU alpha and DNA perturbed by their complex formation, notably those of His C-2 and C-4 protons, downfield shifted C alpha protons in the antiparallel beta-sheet, as well as Arg C delta and Lys C epsilon protons. The results indicated that a beta-sheet region of HU alpha binds to DNA, and also showed that rapid equilibrium occurs on the NMR time scale between bound and unbound states of HU alpha. A few intermolecular nuclear Overhauser effects (NOEs) were also observed between the protein and H1' protons of DNA in the complex, suggesting that HU alpha binds primarily to the minor groove of DNA.

^1H NMR spectroscopy has been used to demonstrate specific binding of rat 80S ribosomes to the major conformer of an antitumor bicyclic hexapeptidic glucoside, RA-XII, isolated from Rubia cordifolia, in a fast exchange process.

The changes in energy metabolites and corresponding force curves were studied during muscle fatigue with respect to excitation frequency (20 and 50Hz) for contracting muscle in situ and by means of 31P nuclear magnetic resonance (NMR) technique in vitro. The rat hind limb muscle group was stimulated via the tibial nerve by 0.5ms duration square pulses at different frequencies for a period of three minutes. The force signals recorded during repeated experiments were fed through an A/D converter and averaged by the use of a desk-top computer. 31P-NMR spectra were recorded from gastrochemius and soleus muscle of resting and after stimulation. Results indicated that 1) Iarge and significant decreases in high energy phosphate compounds (e.g., creatine phosphate and adenosine triphosphate (ATP)) were observed during prolonged electric stimulation at 50Hz in both the gastrocnemius and soleus muscles, 2) during 20Hz stimulation, muscle fiber type dependent changes in energy metabolites were observed: i. e., the gastrocnemius manifested a significant decline in creatine phosphate and ATP contents (p