Tomoko Yamamoto

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Lon protease, a member of the ATP-dependent protease family, regulates numerous cellular systems by degrading specific substrates. Here, we demonstrate that Lon is involved in the regulation of quorum-sensing (QS) signaling systems in Pseudomonas aeruginosa, an opportunistic human pathogen. The organism has two acyl-homoserine lactone (HSL)-mediated QS(More)
A novel cryIC-type gene was isolated from a strain of Bacillus thuringiensis subsp. galleriae. A new polymerase chain reaction (PCR) technique with a set of several oligonucleotide primer pairs specific to the cryIC gene was used to screen a number of B. thuringiensis strains. PCR amplified several DNA fragments ranging from 100 bp to 1 kb for B.(More)
Salmonella enterica serovar Typhimurium delivers a variety of proteins via the Salmonella pathogenicity island 1 (SPI1)-encoded type III secretion system into host cells, where they elicit several physiological changes, including bacterial invasion, macrophage apoptosis, and enteropathogenesis. Once Salmonella has established a systemic infection, excess(More)
Many pathogens use a type III secretion system to translocate virulence proteins (called effectors) in order to adapt to the host environment. To date, many prediction tools for effector identification have been developed. However, these tools are insufficiently accurate for producing a list of putative effectors that can be applied directly for(More)
To test our hypothesis that substitution of domain III of Bacillus thuringiensis delta-endotoxin (Cry) proteins might improve toxicity to pest insects, e.g., Spodoptera exigua, in vivo recombination was used to produce a number of cryIA(b)-cryIC hybrid genes. A rapid screening assay was subsequently exploited to select hybrid genes encoding soluble(More)
Studies on the pathogenesis of Salmonella enterica serovar Typhimurium infections in mice have revealed the presence of two prominent virulence characteristics-the invasion of the nonphagocytic cells to penetrate the intestinal epithelium and the proliferation within host phagocytic cells to cause a systemic spread and the colonization of host organs. We(More)
A two-step procedure was used to place a cryIC crystal protein gene from Bacillus thuringiensis subsp. aizawai into the chromosomes of two B. thuringiensis subsp. kurstaki strains containing multiple crystal protein genes. The B. thuringiensis aizawai cryIC gene, which encodes an insecticidal protein highly specific to Spodoptera exigua (beet armyworm), has(More)
Sulfated glycosaminoglycans (GAGs), including heparan sulfate and chondroitin sulfate, are synthesized on the so-called common GAG-protein linkage region (GlcUAbeta1-3Galbeta1-3Galbeta1-4Xylbeta1-O-Ser) of core proteins, which is formed by the stepwise addition of monosaccharide residues by the respective specific glycosyltransferases.(More)
Thirty-one isolates of bovine viral diarrhea virus (BVDV) isolated within the past 15 years from imported cattle by the Japanese Animal Quarantine Service (AQS) were used in this study in which a 5'-untranslated region of each isolate was genetically analyzed. Twenty-six of the 31 isolates were classified as BVDV1 and the remainder as BVDV2. Phylogenetic(More)
Salmonella enterica serovar Typhimurium, similar to various facultative intracellular pathogens, has been shown to respond to the hostile conditions inside macrophages of the host organism by inducing stress proteins, such as DnaK. DnaK forms a chaperone machinery with the cochaperones DnaJ and GrpE. To elucidate the role of the DnaK chaperone machinery in(More)