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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.  相似文献   
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In order to develop a vaccine against cryptosporidiosis in cattle, we constructed a recombinant bovine herpesvirus-1 (BHV-1) expressing an immunodominant surface protein, p23, of Cryptosporidium parvum sporozoites. In the recombinant virus, the p23 gene under the control of a CAG promoter and a gene coding for an enhanced green fluorescent protein were integrated into the gG gene of BHV-1. Despite a low frequency of homologous recombination, cloning of the recombinants was easy because of the specific fluorescence of the plaques formed by recombinants. These plaques were among the plaques of the nonfluorescent parental virus. All clones selected for fluorescence also contained the p23 gene. In MDBK cells infected with the recombinant BHV-1, the antibody against the p23 protein recognized the p23 protein as an approximately 23-kDa specific band in Western blotting analysis. Rabbits immunized with the recombinant produced IgG against the p23 protein. It was also demonstrated that the sera of immunized rabbits reduced infection of C. parvum sporozoites in HCT-8 cells. The serum of an immunized rabbit reduced infection compared with the normal rabbit serum control. These results indicate that the recombinant BHV-1 induces neutralizing antibodies in rabbits.  相似文献   
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Experiments were done to find whether buckwheat extract ameliorates the renal injury induced by ischemia-reperfusion. In ischemic-reperfused control rats, the activities of antioxidative enzymes in renal tissue and blood and renal parameters deviated from the normal range, indicating dysfunction of the kidneys. In contrast, when buckwheat extract was given orally for 20 consecutive days before ischemia and reperfusion, the activities of the antioxidation enzymes superoxide dismutase, catalase, and glutathione peroxidase were higher, while thiobarbituric acid-reactive substance levels in serum and renal tissue were lower in the treated rats than in the controls. Decreased levels of urea nitrogen and creatinine in serum demonstrated a protective effect against the renal dysfunction caused by ischemia and recirculation. On the other hand, it was demonstrated that buckwheat extract had a protective effect on cultured proximal tubule cells subjected to hypoxia-reoxygenation, probably by preventing oxygen free radicals from attacking the cell membranes.  相似文献   
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Perlecan, a large heparan sulfate proteoglycan, is a component of the basement membrane and other extracellular matrices and has been implicated in multiple biological functions. Mutations in the perlecan gene (HSPG2) cause two classes of skeletal disorders: the relatively mild Schwartz-Jampel syndrome (SJS) and severe neonatal lethal dyssegmental dysplasia, Silverman-Handmaker type (DDSH). SJS is an autosomal recessive skeletal dysplasia characterized by varying degrees of myotonia and chondrodysplasia, and patients with SJS survive. The molecular mechanism underlying the chondrodystrophic myotonia phenotype of SJS is unknown. In the present report, we identify five different mutations that resulted in various forms of perlecan in three unrelated patients with SJS. Heterozygous mutations in two patients with SJS either produced truncated perlecan that lacked domain V or significantly reduced levels of wild-type perlecan. The third patient had a homozygous 7-kb deletion that resulted in reduced amounts of nearly full-length perlecan. Unlike DDSH, the SJS mutations result in different forms of perlecan in reduced levels that are secreted to the extracellular matrix and are likely partially functional. These findings suggest that perlecan has an important role in neuromuscular function and cartilage formation, and they define the molecular basis involved in the difference in the phenotypic severity between DDSH and SJS.  相似文献   
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alpha-Synuclein is one of the major components of intracellular fibrillary aggregates in the brains of a subset of neurodegenerative disorders, including Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, and Hallervorden-Spatz disease, which are referred to as alpha-synucleinopathies. We have shown previously (Fujiwara, H., Hasegawa, M., Dohmae, N., Kawashima, A., Masliah, E., Goldberg, M. S., Shen, J., Takio, K., and Iwatsubo, T. (2002) Nat. Cell Biol. 4, 160-164) that alpha-synuclein deposited in synucleinopathy brains is extensively phosphorylated at Ser-129 and migrates at 15 kDa. Here we examined the biochemical characteristics of the additional, higher molecular mass species of phosphorylated alpha-synuclein-positive polypeptides that also are recovered in the Sarkosyl-insoluble fraction of synucleinopathy and migrate at about 22 and 29 kDa. These 22 and 29 kDa bands were positive for three different anti-ubiquitin antibodies and comigrated perfectly with in vitro ubiquitinated alpha-synuclein that may correspond to mono- and diubiquitinated alpha-synuclein, respectively. Furthermore, cyanogen bromide cleavage of the 22 and 29 kDa polypeptides shifted the mobility to 19 and 26 kDa, respectively, and they retained immunoreactivity for both ubiquitin and alpha-synuclein. Finally, protein sequence analysis showed that the 19 kDa band contained two amino-terminal sequences of alpha-synuclein and ubiquitin. These results strongly suggest that phosphorylated alpha-synuclein is targeted to mono- and diubiquitination in synucleinopathy brains, which may have implications for mechanisms of these diseases.  相似文献   
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