Serological Typing of 31 Achromogenic and 40 Melanogenic Pseudomonas aeruginosa Strains

Thirty-one achromogenic and 40 melanogenic Pseudomonas aeruginosa strains were studied with 10 monovalent typing sera (3). Twenty-one of the achromogenic (67.7%) and seven of the melanogenic (17.5%) strains were agglutinated by one of the 10 typing sera. Ten achromogenic and 33 melanogenic strains were not agglutinated by any of the 10 typing sera. As far as this set of antisera is concerned, the typability of achromogenic and melanogenic P. aeruginosa strains appears to be much lower than that of the chromogenic, nonmelanogenic strains of the species reported previously.     

Cell-surface changes during in vitro differentiation of pluripotent embryonal carcinoma cells

When aggregates of HM-1 embryonal carcinoma (EC) cells were exposed to 10(-6) M retinoic acid for 2 days and cultured in medium lacking retinoic acid, they differentiated to nerve cells, endoderm cells, and myoblasts. Cells 2 days after initial exposure to retinoic acid were not significantly different from the parental EC cells, as judged by cell-surface architecture and by reactivity to lectins. On the fourth day, the surface of the aggregates was covered with two kinds of cells distinguishable from the parental cells. The round cells with short villi seemed to be precursors to endoderm cells. Receptors for Dolichos biflorus agglutinin (DBA) newly appeared and receptors for peanut agglutinin (PNA) were still expressed on their surfaces. The other cells, which were round cells with a few processes, might be precursors to nerve cells. PNA receptors had disappeared from their surfaces, and DBA receptors were not expressed. On the sixth day of differentiation, possible precursors to myoblasts were detected; they were flat cells with smooth surfaces. These cells lacked cell-surface receptors for the two lectins, while the precursor cells and the myoblasts excreted intercellular fibers reacting with PNA. HM-1 cells synthesized much embryoglycan, the structure of which was similar to that of the glycan isolated from quasinullipotent F9 cells. The only difference was that the glycan from HM-1 cells lacked DBA binding sites. Synthesis of fucosylated embryoglycan mainly decreased between the second and fourth day of differentiation. As above, cell-surface changes occurred mainly between the second and fourth day. The period seems to be important in determining the fate of the cells, since endoderm cells were scarcely seen among differentiated cells which had been continuously exposed to 10(-6) M retinoic acid during the period.     

Transfer of Two Burkholderia and An Alcaligenes Species to Ralstonia Gen. Nov.

Based on the results of phenotypic characterization, cellular lipid and fatty acid analysis, phylogenetic analysis of 16S rDNA nucleotide sequences and rRNA-DNA hybridization, Burkholderia pickettii, Burkholderia solanacearum and Alcaligenes eutrophus are transferred to the new genus Ralstonia, and Ralstonia pickettii (Ralston, Palleroni and Doudoroff 1973) comb. nov., Ralstonia solanacearum (Smith 1896) comb, nov., and R. eutropha (Davis 1969) comb. nov. are proposed. The type species of the new genus is R. pickettii. Type strain of R. pickettii is ATCC 27511^T, of R. solanacearum is ATCC 10696^T, and of R. eutropha is ATCC 17697^T.     

Biosynthesis of a blood group H1 antigen by α1,2-fucosyltransferase in PC12 cells

We have examined the expression of GDP-fucose: glycosphingolipid fucosyltransferase activity in PC12 cells and PC12 sublines in relation to the neuronal differentiation induced by nerve growth factor (NGF) or dexamethasone. Transfer of fucose to paragloboside (nLc₄Cer) yielded a product which was determined to be a blood group H₁ antigen (Fuc1-2Gal1-4GlcNAc1-3Gal1-4Glc-Cer) by gas chromatography/mass spectrometry analysis and enzymatic hydrolysis, suggesting that PC12 cells have an 1,2-fucosyltransferase. Lactosylceramide was also fucosylated at a reduced rate. When the differentiation of PC12 cells and PC12 subline cells, PC12D and MR31, was induced by exposure to either NGF or dexamethasone, the fucosyltransferase activity for nLc₄Cer was found to decrease in both cell lines, suggesting the association with cell differentiation. This is the first report of the presence of an 1,2-fucosyltransferase in cultured neuronal cell lines which catalyses thein vitro biosynthesis from nLc₄Cer of a type-2 chain glycosphingolipid having the blood group H₁ determinant. The disaccharides, -lactose andN-acetyllactosamine, were also fucosylated by PC12 cell enzyme, although the specificity for the carbohydrate structure was different from that for glycosphingolipids.Abbreviations Glc d-glucose - Gal d-galactose - GlcNAc N-acetyl-d-glucosamine - Fuc l-fucose - Cer ceramide - nLc₄Cer neolactotetraosylceramide (paragloboside) - GDP guanosine diphosphate - CDP cytidine diphosphate - CTP cytidine triphosphate - NGF nerve growth factor - DX dexamethasone - GC/MS gas chromatography/mass spectrometry     

Expression profile of mouse BWF1, a protein with a BEACH domain, WD40 domain and FYVE domain

We isolated a mouse cDNA encoding a protein that contains a BEACH domain, 5 WD40 repeats and a FYVE domain, which we designated as BWF1. The mRNA is approximately 10 kb in size and encodes a protein consisting of 3508 amino acids with a predicted molecular weight of 385 kDa. BWF1 has 45% homology with the Drosophila protein, blue cheese (BCHS). The BWF1 gene consists of 67 exons, which span 270 kb of genomic sequence, and has been mapped to mouse chromosome 5. Northern blot analysis revealed that it was strongly expressed in the liver, moderately in the kidney and testis, and weakly in the brain of adult mice. During the development of the mouse brain, BWF1 mRNA was abundant on embryonic day (E) 14-16; after birth, the level of BWF1 mRNA expression decreased markedly to reach the adult level at postnatal day 3. In situ hybridization analysis revealed that the expressed BWF1 mRNA was restricted to the marginal region both in E14 and E16 embryonic brain, but became diffuse after birth. Confocal microscopy studies of the epitope-tagged BWF1 protein showed that the protein was a cytoplasmic one.     

Immunomodulatory function of lactic acid bacteria

Using mice, we found that oral administration of Bifidobacterium breve YIT4064 (B. breve) activated the humoral immune system, augmented anti-rotavirus IgA production or anti-influenza virus (IFV) IgG production and protected against rotavirus infection or influenza infection, respectively. Furthermore, when the B. breve was given to infants from an infant home, there was a significant reduction of the frequency of rotavirus shedding in stool samples during the administration of the bacteria. It was also found, again using mice, that oral administration of Lactobacillus casei strain Shirota (LcS) stimulated type 1 helper T (Th1) cells, activated the cellular immune system and inhibited incidence of tumors and IgE production. These results demonstrated that these two strains of lactic acid bacteria modulated the different immune systems each in its own way and prevented against various diseases.     

Biliary metabolites of estriol in the rat

Following the subcutaneous administration of estriol-6,7-³H to rats, biliary metabolites were identified and quantitated. Approximately 70% of the metabolites were excreted in the form of “glucosiduronate” conjugates. 3, 17β-Dihydroxy-2-methoxy-1,3,5(10)-estratrien-16-one was the major metabolite in this conjugate fraction. Significant amounts of 3,17β-dihydroxy-1,3,5(10)-estratrien-16-one and 2,3,17β-trihydroxy-1,3,5(10)-estratrien-16-one, as well as smaller quantities of 1,3,5(10)-estratriene-2,3,16α,17β-tetrol and 2-methoxy-1,3,5(10)-estratriene-3,16α, 17β-triol, were also found. In 17α-ethinylestradiol - treated animals, the rate of excretion of radioactivity and the proportion of 16-oxo-17β-ol metabolites found in the “glucosiduronate” fraction were reduced.     

Distribution and phylogenetic diversity of the subsurface microbial community in a Japanese epithermal gold mine

Distribution and phylogenetic diversity of microbial communities in hot, deep underground environments in the Hishikari epithermal gold mine, southern part of Kyushu, Japan, were evaluated using molecular phylogenetic analyses. Samples included drilled cores such as andesitic volcanic rock (0.95-1.78 Ma) and the oceanic sedimentary basement rock of Shimanto-Supergroup (100 Ma), as well as geothermal hot aquifer waters directly collected from two different sites: AW-site (71.5 degrees C, pH 6.19) and XW-site (85.0 degrees C, pH 6.80) at a depth of 350 mbls (meters below land surface). Based on PCR-amplified 16S rRNA gene clone analysis, the microbial communities in the drilled cores and the hot aquifer water from the XW-site consisted largely of the 16S rRNA gene sequences, closely related to the sequences often found in marine environments, while the aquifer water from the AW-site contained 16S rRNA gene sequences representing members of Aquificales, thermophilic methanotrophs within the gamma-subdivision of the Proteobacteria and uncultivated strains within the beta-subdivision of Proteobacteria. The cultivable microbial community detected by enrichment cultivation analysis largely matched that detected by the culture-independent molecular analysis.     

Evaluation of the relative contribution of p53-mediated pathway in X-ray-induced apoptosis in human leukemic MOLT-4 cells by transfection with a mutant p53 gene at different expression levels

There are several pathways leading to apoptosis. It is not clear whether cells choose one of them or use multiple processes when they commit to apoptosis. MOLT-4 cells undergo apoptosis after X-irradiation through the p53-dependent pathway and/or ceramide signal. To evaluate the relative contribution of these pathways, we studied effects of the expression of various levels of transfected murine mutant p53 cDNA (TGC-->CGC of codon 173, corresponding to codonl76 in human p53) on the induction of apoptosis in X-irradiated or heated MOLT-4 cells. When survival was determined by the dye-exclusion test at 24 h after irradiation, the percentage of X-ray- or heat-induced dead cells was markedly decreased, depending on the expression level of mutant p53 protein in transfected clones. The appearance of apoptotic cells as determined by morphological changes was also decreased. These inhibitions were almost complete at 24 h after irradiation with X-rays in the case of the highest-expressing clone. p21 WAF1 protein was increased in MOLT-4 cells after X-irradiation, but not in the transfectant. These results suggest that murine mutant p53 protein has a dominant-negative effect against normal p53 in MOLT-4, and that the X-ray-induced apoptosis in MOLT-4 is fully p53-dependent.