Reduction by phytate-reduced soybean beta-conglycinin of plasma triglyceride level of young and adult rats.

This study examined the effects of soybean beta-conglycinin, from which phytate was mostly removed, on the plasma lipids in young and adult rats. Male Wistar young (6 week-old) and adult (21 week-old) rats were fed high cholesterol diets containing 20% casein, soy protein isolate (SPI), or soybean beta-conglycinin for 10 days. In young rats, although the food intake of the beta-conglycinin group was higher than those of the casein and SPI groups, the weight gain was significantly lower than those of the other groups. However, in adult rats, the weight gain was not different among the groups. In young and adult rats, relative liver weights of SPI and beta-conglycinin groups were significantly lower than that of the casein group, and the degree of the reduction was more marked in the beta-conglycinin group than in the SPI group. In young rats, the plasma triglyceride level was significantly lower in the SPI and beta-conglycinin groups than that in the casein group. In addition, the plasma triglyceride level of the beta-conglycinin group was significantly lower than that of the SPI group. Plasma total cholesterol levels of the SPI and beta-conglycinin groups were significantly lower than that of the casein group. However, there was little difference in the lowering effect between SPI and beta-conglycinin. These results indicate that soybean beta-conglycinin may have lowering functions not only on plasma total cholesterol level, but also on plasma triglyceride level.     

Molecular phylogeny and evolution of subsection Magnicellulatae (Erysiphaceae: Podosphaera) with special reference to host plants

The subsection Magnicellulatae of the genus Podosphaera section Sphaerotheca belongs to the tribe Cystotheceae of the Erysiphaceae, which has the characteristic of producing catenate conidia with distinct fibrosin bodies. In this study, we newly determined the nucleotide sequences of the D1/D2 domains of the 28S rDNA region and the sequences of the rDNA internal transcribed spacer (ITS) region to investigate the relationships between the phylogeny of this fungal group and their host plants. The results indicated that the 28S rDNA region is too conservative for phylogenetic analysis of this fungal group. The phylogenetic analysis using 95 ITS sequences demonstrated that two or more Magnicellulatae taxa often infect the same plant genus or species. Although there is a close relationship between Magnicellulatae and asteraceous hosts, this association seems to be not as strict as that between Golovinomyces and the Asteraceae. The difference between the two fungal groups may be explained by their different evolutionary timing.     

Perfusion culture apparatus for suspended mammalian cells

A variety of processes have been proposed for mammalian cell culture in the commercial production of useful substances (e.g., monoclonal antibodies, therapeutic and diagnostics proteins). Among them, the perfusion culture of suspended non-immobilized cells is the most advantageous. Perfusion culture can be classified by the separation process of suspended cells from the culture mixture into three types, namely filtration, gravitational settling and centrifugation. From a commercial point of view, the present situation and technical problems of suspended-cell perfusion culture will be reviewed based on the three types, The recent development of perfusion culture has been carried out mainly on the filtration separation process, but the centrifugation process seems to have a promising future because of operation stability and scale-up feasibility. The reasons will be explained in details.     

Identification of Mutations Involved in the Requirement of Potassium for Growth of Typical Melissococcus plutonius Strains

Melissococcus plutonius is a fastidious honeybee pathogen, and the addition of KH₂PO₄ to culture medium is required for its growth. Using genome sequences and a newly developed vector, we showed that mutations in genes encoding Na⁺/H⁺ antiporter and cation-transporting ATPase are involved in the potassium requirement for growth.     

Isolation and characterization of recoverin-like Ca(2+)-binding protein from rat brain.

Rat brain was found, by immunoblot analysis, to have a protein of Mr 23,000 (P23k) that was clearly different from recoverin and was labeled with an antiserum raised against the NH2-terminus of recoverin. P23k could not be detected by an antiserum raised against the COOH-terminus of recoverin. Blots with 45Ca demonstrated that P23k bound Ca2+. This calciprotein was further purified by Ca(2+)-dependent hydrophobic interaction and ion-exchange chromatography. In SDS polyacrylamide gel electrophoresis, P23k had an apparent Mr of 21,000 in the presence of 10 microM Ca2+ and 23,000 in the absence of Ca2+ (0.1 mM EGTA). The isoelectric point of P23k was 5.6. Ca(2+)-binding analysis indicated that P23k bound 2 moles of Ca2+ per mole of protein and had two binding sites with dissociation constants of 13 microM and 0.2 microM. Purified P23k bound to the crude membrane fractions from the cerebellum, cerebrum and retina in a Ca(2+)-dependent manner. Partial amino acid sequence analysis of proteolytic fragments of P23k revealed the sequence homology between P23k and recoverin. These results suggested that P23k may act as a Ca(2+)-sensitive regulator by forming a complex with its target on the membrane.     

Morphophylogenetic study revealed that Erysiphe gracilis (powdery mildew of evergreen oaks,Erysiphales) is a species complex consisting of six different species

Erysiphe gracilis is a powdery mildew species that occurs on evergreen oak species belonging to Quercus subgen. Cyclobalanopsis in East Asia (China and Japan). In a previous report, we found that E. gracilis var. gracilis is divided into four genotypes each of them forming a separate clade with strong bootstrap support. In this study, we further investigated genotype speciation in E. gracilis var. longissima occurring on Q. acuta and Q. sessilifolia, and found that this variety is also divided into two distinct genotypes. These results suggested that E. gracilis represents a species complex consisting of six different species. Based on detailed morphological examinations correlating with results of molecular sequence analyses, we propose to divide E. gracilis into six species, encompassing three new species (E. uncinuloides, E. pseudogracilis, and E. longiappendiculata), one new name (E. longifilamentosa), and two known species (E. gracilis s. str. and E. hiratae). A key to the species concerned is provided.     

Asymmetry in the self-sustained oscillation ofPhysarum plasmodial strands

Summary The characteristics of the self-sustained oscillation in the plasmodial strand ofPhysarum polycephalum have been investigated in one steady and two transient conditions. An isolatedPhysarum strand changes its length periodically when it is suspended. In the behaviour of the self-sustained oscillation under the conditions, we provide the first demonstration that the changes in the periods of the oscillation can be ascribed to effects on the shortening phase, while the lengthening periods are almost unaffected. This result means that the asymmetric self-sustained oscillation of thePhysarum strand is composed of an active contracting process, presumably due to actin filaments and myosin-like molecules in the strand, and a passive lengthening process which is merely an extension of the strand under a load.     

Differential expression of gap junction proteins connexin26, 32, and 43 in normal and crush-injured rat sciatic nerves. Close relationship between connexin43 and occludin in the perineurium.

We immunohistochemically and morphometrically examined the expression of gap junction protein connexin (Cx) in normal and crush-injured rat sciatic nerves using confocal laser scanning microscopy. Cx26 was localized in the perineurium and Cx43 was present in the perineurium and the epineurium, whereas Cx32 was confined to the paranodal regions of the nodes of Ranvier. Double labeling for connexins and laminin revealed that Cx43 was localized in multiple layers of the perineurium, whereas Cx26 was confined to the innermost layer. Double labeling for connexins and a tight junction protein, occludin, showed that occludin frequently coexisted with Cx43 but existed separately from Cx26 in the perineurium. After crush injury, the pattern of normal Cx32 expression was initially lost but recovered, whereas Cx43 rapidly appeared in the endoneurium and its expression was subsequently attenuated. Although crush injury produced no apparent alteration in Cx43 and occludin in the perineurium, a rapid increase and a subsequent decrease in the frequency of Cx26-positive spots during nerve regeneration were shown by morphometric analysis. These results indicate that Cx26, Cx32, and Cx43 are expressed differently in various types of cells in peripheral nerves and that their expressions are differentially regulated after injury. The expression of connexins and occludin in the perineurium suggests that perineurial cells are not uniform in type and that the regulation of gap junctions and tight junctions is closely related in the perineurium.