Strain differences to effects of aging on concentrations of amino acids in cerebrospinal fluid between Sprague Dawley rat and Wistar Kyoto rat.

Age-related alterations and differences of weights and those of amino acid concentrations in the cerebrospinal fluid (CSF) were evaluated between Sprague Dawley (SD) rats and Wistar Kyoto (WKY) rats from eight to twenty weeks of age. The weights of SD rats were heavier than WKY rats at all ages. The age-related alterations of the CSF concentration of many amino acids within each strain were significant but showed no significant trend with age. Between the strains, the concentration differences of excitatory and inhibitory amino acids were not frequent although the concentrations of arginine, alanine and threonine were significantly higher in SD rats than in WKY rats. These results suggest that the different CSF concentrations of amino acids may relate to characteristics of rat strains.     

Biosynthesis of triterpenoids from amino acids in Pisum sativum. The distribution of the radioactivity in squalene biosynthesized from radioisotopically labelled l-leucine and l-valine

Radioisotopically labelled l-leucine and l-valine were fed to Pisum sativum and incorporated into squalene and β-amyrin. Chemical degradation of the radioactive squalene revealed an equal distribution of the radioactivity in the isopentenyl pyrophosphate(IPP)-derived and the 3,3-dimethylallyl pyrophosphate(DMAPP)-derived moieties of the squalene molecule, unlike the unbalanced distribution in favour of the DMAPP-derived moiety of a monoterpenoid molecule biosynthesized from these amino acids by higher plants.     

Preparation of multilayers containing chlorophylla and/or phosphatidylcholine and chemical stability of chlorophylla molecules in the multilayers

Summary The Langmuir-Blodgett films consisting of mixed monolayers containing chlorophylla (Chl-a) and/or phosphatidylcholine with various molar ratios could be well prepared on glass plates previously covered with three monolayers of cadmium eicosanate. Thin-layer and high-performance liquid chromatographic examinations revealed that the photostability of Chl-a molecules in various media is in the following order: the mixed mono- or multilayers >pure Chl-a mono- or multilayersorganic solvents.     

Crystallization and preliminary X-ray analysis of plant class I chitinase from rice

We report here on crystallization and preliminary X-ray analysis of plant class I chitinase from rice (OsChia1b). Similar single crystals of full-length OsChia1b were obtained under two independent conditions. The crystals grown under these conditions diffracted up to 2.1 and 2.5 angstroms resolution, respectively, at a synchrotron beamline, and were found to belong to the tetragonal space group P4(3)2(1)2.     

Discovery of potent, selective, orally active benzoxazepine-based Orexin-2 receptor antagonists

During our efforts to identify a series of potent, selective, orally active human Orexin-2 Receptor (OX2R) antagonists, we elucidated structure-activity relationship (SAR) on the 7-position of a benzoxazepine scaffold by utilizing Hammett σ(p) and Hansch-Fujita π value as aromatic substituent constants. The attempts led to the discovery of compound 1m, possessing good in vitro potency with over 100-fold selectivity against OX1R, good metabolic stability in human and rat liver microsome, good oral bioavailability in rats, and in vivo antagonistic activity in rats by oral administration.     

Urea sensitization caused by separation of Helicobacter pylori RNA polymerase beta and beta' subunits

BACKGROUND: The beta and beta' subunits of RNA polymerase are fused in all Helicobacters, but separate in most other taxa. Prior studies had shown that this fusion is not essential for viability in culture or in vivo, but had not tested it for potentially important quantitative effects on phenotype. METHODS: The effect of separating rpoB and rpoC sequences on Helicobacter pylori growth was tested in culture and during mouse infection. RESULTS: Derivatives of strains X47 and SS1 carrying this "rpoBCsplit" allele colonized mice less vigorously than their wild-type parents in competition tests. With X47 rpoBCsplit, this reduced vigor was evident in wild-type mice, whereas with SS1 rpoBCsplit it was seen only in cytokine IL-10- and IL-12beta-deficient mice. In culture, the rpoBCsplit allele sensitized each of four strains tested (X47, SS1, 88-3887, and AM1) to urea, a metabolite that is secreted into the gastric mucosa; urea sensitization was more severe in X47 than in SS1 genetic backgrounds. The rpoBCsplit allele also caused poorer growth on Ham's F12 agar, a nutritionally limiting medium, but had little effect on sensitivity to mild acidity. CONCLUSIONS: H. pylori's normal RNA polymerase beta-beta' subunit fusion contributes quantitatively to fitness. We propose that urea, although important to H. pylori in vivo, also be considered inhibitory; and that H. pylori's natural beta-beta' subunit fusion helps it cope with urea exposure.     

Function of Pax1 and Pax9 in the sclerotome of medaka fish

We examined the expression and functions of Pax1 and Pax9 in a teleost fish, the medaka Oryzias latipes. While Pax1 and Pax9 show distinct expression in the sclerotome in amniotes, we could not detect the differential expression of Pax1 and Pax9 in the developing sclerotome of the medaka. Furthermore, unlike the mouse, in which Pax1 is essential for development of the vertebral body, and where the neural arch is formed independent of either Pax1 or Pax9, our morpholino knockdown experiments revealed that both Pax1 and Pax9 are indispensable for the development of the vertebral body and neural arch. Therefore, we conclude that after gene duplication, Pax1 and Pax9 subfunctionalize their roles in the sclerotome independently in teleosts and amniotes. In Stage-30 embryo, Pax9 was strongly expressed in the posterior mesoderm, as was also observed for mouse Pax9. Since this expression was not detected for Pax1 in the mouse or fish, this new expression in the posterior mesoderm likely evolved in Pax9 of ancestral vertebrates after gene duplication. Two-month-old fish injected with Pax9 morpholino oligonucleotide showed abnormal morphology in the tail hypural skeletal element, which may have been related to this expression.     

Some common properties of lectins from marine algae

Twelve kinds of lectins isolated from four species of marine algae, Boodlea coacta (Chlorophyta) and Hypnea japonica, Carpopeltis flabellata and Solieria robusta (Rhodophyta), were compared for their chemical and biological properties. These lectins were proteins or glycoproteins, similar to terrestrial plant lectins. However, unlike most terrestrial plant lectins, they had a small molecular size (4,200 to 25,000 daltons), were mostly monomeric, and had no affinity for monosaccharides. They strongly agglutinated trypsin-treated rabbit erythrocytes, and their activities commonly were inhibited by glycoproteins bearing N-glycans. From hemagglutination-inhibition tests with various glycoproteins and related compounds, it was found that B. coacta lectins recognize high-mannose N-glycans; H. japonica lectins complex N-glycans, and C. flabellata and S. robusta lectins recognize both types of N-glycans.