title: Genes induced by a high-oxygen environment in Entamoeba histolytica.
abstract: Entamoeba histolytica, although a microaerophilic protozoan parasite, encounters a high-oxygen environment, during invasive amoebiasis. The parasite requires specific regulation of certain proteins to maintain its physiological functions to survive in the more oxygenated condition. Our endeavor was to know how does amoeba adapt itself in a high-oxygen environment. Reactive oxygen species (ROS) was found to accumulate in an increasing concentration within the stressed trophozoites in a time-dependent manner. Increased cytopathic activity was detected at 2h in high-oxygen-exposed E. histolytica lysate compared to lysate of normal E. histolytica trophozoites by Ussing chamber assay. The differential display and semi-quantitative polymerase chain reaction showed overexpression in the mRNA levels of thiol-dependent peroxidase (Eh29), superoxide dismutase (SOD), EhCP5, G protein, HSP70, and peptidylprolyl isomerase at different time periods of oxidative stressed trophozoites compared to normally cultured E. histolytica. Analyses of the up-regulated genes that are associated with stress response, viz., signal transduction, tissue destruction, and oxidative stress management, including enhanced expression of a 29-kDa Eh29, suggest that this organism has several protective mechanisms to deal with oxidative stress during invasion.
authors.affiliation: Department of Microbiology, National Institute of Cholera and Enteric Diseases, P-33 C.I.T. Road, Scheme-XM, Kolkata-700 010, West Bengal, India.
authors.forename: Md Ali
authors.initials: MA
authors.lastname: Akbar
authors.forename: Nabendu Sekhar
authors.initials: NS
authors.lastname: Chatterjee
authors.forename: Paramita
authors.initials: P
authors.lastname: Sen
authors.forename: Anjan
authors.initials: A
authors.lastname: Debnath
authors.forename: Amit
authors.initials: A
authors.lastname: Pal
authors.forename: Tanmoy
authors.initials: T
authors.lastname: Bera
authors.forename: Pradeep
authors.initials: P
authors.lastname: Das
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D000954:Antigens, Surface / Q000235:genetics / Q000378:metabolism; D004748:Entamoeba histolytica / Q000235:genetics* / Q000378:metabolism*; D020869:Gene Expression Profiling; D017125:Genes, Protozoan; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics; D018384:Oxidative Stress; D019696:Peptidylprolyl Isomerase / Q000235:genetics / Q000378:metabolism; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D017382:Reactive Oxygen Species / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: C434108:29 kDa antigen, Entamoeba histolytica; D000954:Antigens, Surface; D018840:HSP70 Heat-Shock Proteins; D015800:Protozoan Proteins; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D011994:Recombinant Proteins; D010544:Peroxidases; C058652:thiol-dependent peroxidase; D013482:Superoxide Dismutase; D019696:Peptidylprolyl Isomerase