文献类型： 外文期刊

作者： Li, J ¹ ; Zhang, WB ² ; Loukas, A ² ; Lin, RY ² ; Ito, A ² ; Zhang, LH ² ; Jones, M ² ; McManus, DP ² ;

作者机构： 1.Queensland Inst Med Res, Australian Ctr Int & Trop Hlth & Nutr, Mol Parasitol Lab, Brisbane, Qld 4029, Australia

2.Queensland Inst Med Res, Australian Ctr Int & Trop Hlth & Nutr, Mol Parasitol Lab, Brisbane, Qld 4029, Australia; Univ Queensland, Brisbane, Qld 4029, Australia; Xinjiang Acad Anim Sci, Vet Res Inst, Xinjiang 830000, Peoples R China; Asahikawa Med Coll, Dept Parasitol, Asahikawa, Hokkaido 0788510, Japan

关键词： Echinococcus granulosus;thioredoxin peroxidase;thiol-dependent peroxidase activity;antioxidant;H2O2 tolerance;peroxiredoxin gene superfamily

期刊名称：GENE （ 影响因子：3.688； 五年影响因子：3.329 ）

ISSN： 0378-1119

年卷期： 2004 年 326 卷

页码：

收录情况： SCI

摘要： A full-length cDNA sequence coding for Echinococcus granulosus thioredoxin peroxidase (EgTPx) was isolated from a sheep strain protoscolex cDNA library by immunoscreening using a pool of sera from mice infected with oncospheres. EgTPx expressed as a fusion protein with glutathione S-transferase (GST) exhibited significant thiol-dependent peroxidase activity that protected plasmid DNA from damage by metal-catalyzed oxidation (MCO) in vitro. Furthermore, the suggested antioxidant role for EgTPx was reinforced in an in vivo assay, whereby its expression in BL21 bacterial cells markedly increased the tolerance and survival of the cells to high concentrations of H2O2 compared with controls. Immunolocalization studies revealed that EgTPx was specifically expressed in all tissues of the protoscolex and brood capsules. Higher intensity of labelling was detected in many, but not all, calcareous corpuscle cells in protoscoleces. The purified recombinant EgTPx protein was used to screen sera from heavily infected mice and patients with confirmed hydatid infection. Only a portion of the sera reacted positively with the EgTPx-GST fusion protein in Western blots, suggesting that EgTPx may form antibody-antigen complexes or that responses to the EgTPx antigen may be immunologically regulated. Recombinant EgTPx may prove useful for the screening of specific inhibitors that could serve as new drugs for treatment of hydatid disease. Moreover, given that TPx from different parasitic phyla were phylogenetically distant from host TPx molecules, the development of antiparasite TPx inhibitors that do not react with host TPx might be feasible. (C) 2003 Elsevier B.V. All rights reserved.