Abortive Infection of L Cells by Influenza B Virus: Defect in Bud Formation

Host-dependent restriction of influenza B virus replication in L cells was analysed in comparison with productive infection in MDCK or 1–5C-4 cells. The synthesis and intracellular distribution of virus-specific proteins and the production of cytoplasmic ribonucleoproteins in nonpermissive L cells were similar to those in permissive MDCK cells. However, an electron microscopic study of infected L cells showed neither extracellular virions nor budding virus particles on the cell surface, in contrast to MDCK cells which produced numerous virus particles. PAGE analysis of the plasma membrane isolated from the cells demonstrated no significant difference in the composition of viral polypeptides between permissive 1-5C-4 and nonpermissive L cells. It was noted that the abortiveness of influenza B virus infection in L cells may be due to a defect in host cell function involved in the initiation of virus budding.     

Characterization of translucent segments observed in an smbA mutant of Escherichia coli

Abstract The smbA gene of Escherichia coli is essential for cell proliferation. The smbA2 mutant shows cold-sensitive colony formation at 22°C. A novel morphological phenotype, formation of a translucent segment at midcell or at a cell pole, was observed by phase-contrastt microscopy at a high frequency in the smbA2 mutant cells incubated in L medium lacking NaCl at 22°C, but not observed in L medium containing 1% NaCl or 20% sucrose at the same temperature. No translucent segment was observed in the wild-type cells in any of the media used. Electron microscopic observation revealed that the translucent segments resulted from the enlargement of a periplasmic space by separation of the inner membrane from the peptidoglycan layer and the outer membrane.     

The Alarm Pheromone of the Mite Suidasia medanensis OUDEMANS, 1924 (Acariformes,Suidasiidae)

The stored-product mite Suidasia medanensis has been found in human-provided habitats in Japan. The mite uses neral as the alarm pheromone, and also secretes (Z,E)- and (£,£)-farnesal, which were isolated from an astigmatid mite for the first time. On the other hand, S. medanensis is the only mite out of fifteen species investigated so far that does not secrete volatile hydrocarbons along with the alarm pheromone, though 9-nonadecene and 6,9-nonadecadiene were found in a hexane extract of the mite. GC-MS, ^JH-NMR and ¹³C-NMR of the four isomers of synthetic farnesal, which were isolated by LC and preparative GLC, cleared up some confusion in the literature concerning the stereochemistry of this sesquiterpenoid.     

Protein resonance assignment by solid-state NMR based on 1H-detected 13C double-quantum spectroscopy at fast MAS

Journal of Biomolecular NMR - Solid-state NMR spectroscopy is a powerful technique to study insoluble and non-crystalline proteins and protein complexes at atomic resolution. The development of...     

Biofuel and energy crops: high-yield Saccharinae take center stage in the post-genomics era

The Saccharinae, especially sugarcane, Miscanthus and sorghum, present remarkable characteristics for bioenergy production. Biotechnology of these plants will be important for a sustainable feedstock supply. Herein, we review knowledge useful for their improvement and synergies gained by their parallel study.     

Fractionation of Main Components and Their Subunits of Soybean Proteins

The water-extracted proteins, C and D fractions prepared from defatted soybean meals were fractionated by a method of gel filtration with Sephadex G–200, resulting in higher purification of the C and D components. The dissociated subunits of the C and D components were seen as bands B and B′ on the starch-gel electrophoretical pattern of system without urea. By the starch-gel electrophoresis in system with urea, the subunits of C component were mainly corresponding to the bands 7, 8 and 9, and those of the D component mainly to the band 10. Those subunits were fractionated by column chromatography on DEAE-cellulose contained urea.