title: Characterization of the thioredoxin peroxidase from Cryptosporidium parvum.
abstract: Cryptosporidium parvum can survive exposure to harsh environmental conditions, various disinfectants, and high doses of γ-radiation. Recently, it was found that the expression of thioredoxin peroxidase (CpTPx) in C. parvum increased after a high dose of γ-irradiation to the parasite. CpTPx is a two-cysteine peroxiredoxin that contains cysteines at positions 49 and 170. Recombinant CpTPx fused to an N-terminal hexahistidine sequence, (His)(6)-CpTPx, exhibited substantial thiol-dependent peroxidase activity that protected plasmid DNA from damage by metal-catalyzed oxidation in vitro. (His)(6)-CpTPx was used to screen sera from C. parvum-infected mice and humans for antibodies against CpTPx. In Western blots, 10% of the mouse sera and 20% of the human sera reacted with (His)(6)-CpTPx, suggesting that after infection by C. parvum CpTPx can induce a host-immune reaction but is not a major antigen. Immunolocalization studies revealed that CpTPx is expressed mainly in the cytoplasm of C. parvum at various developmental stages.
authors: Department of Environmental and Tropical Medicine, Konkuk University, School of Medicine, Seoul 143-701, Republic of Korea.
authors: Migyo
authors: M
authors: Joung
authors: Sejoung
authors: S
authors: Yoon
authors: Kyungmi
authors: K
authors: Choi
authors: Joung-Yeon
authors: JY
authors: Kim
authors: Woo-Yoon
authors: WY
authors: Park
authors: Jae-Ran
authors: JR
authors: Yu
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015153:Blotting, Western; D016785:Cryptosporidium parvum / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D005260:Female; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007150:Immunohistochemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D010084:Oxidation-Reduction; D054464:Peroxiredoxins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D010802:Phylogeny; D011817:Rabbits; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D016415:Sequence Alignment; D013047:Specific Pathogen-Free Organisms
chemical_list: D000953:Antigens, Protozoan; D007106:Immune Sera; D011994:Recombinant Proteins; D054464:Peroxiredoxins