Proteomic profiling of the infective trophozoite stage of Acanthamoeba polyphaga

Abstract

Acanthamoeba polyphaga is a free-living protozoan pathogen, whose infective trophozoite form is capable of causing a blinding keratitis and fatal granulomatous encephalitis in humans. The damage caused by A. polyphaga trophozoites in human corneal or brain infections is the result of several different pathogenic mechanisms that have not yet been elucidated at the molecular level. We performed a comprehensive analysis of the proteins expressed by A. polyphaga trophozoites, based on complementary 2-DE MS/MS and gel-free LC-MS/MS approaches. Overall, 202 non-redundant proteins were identified. An A. polyphaga proteomic map in the pH range 3-10 was produced, with protein identification for 184 of 370 resolved spots, corresponding to 142 proteins. Additionally, 94 proteins were identified by gel-free LC-MS/MS. Functional classification revealed several proteins with potential importance for pathogen survival and infection of mammalian hosts, including surface proteins and proteins related to defense mechanisms. Our study provided the first comprehensive proteomic survey of the trophozoite infective stage of an Acanthamoeba species, and established foundations for prospective, comparative and functional studies of proteins involved in mechanisms of survival, development, and pathogenicity in A. polyphaga and other pathogenic amoebae.

Artemether Exhibits Amoebicidal Activity against Acanthamoeba castellanii through Inhibition of the Serine Biosynthesis Pathway

“…The protein expression diversity analysis in different parasitic species might be used to develop potential drug targets or diagnostic biomarkers and explain the molecular mechanisms underlying the host-parasite interaction. Analysis of protein expression under different conditions is important for elucidating the stress response of Acanthamoeba, but the range of protein expression has not been investigated except for a study on the encystment of Acanthamoeba (30). Our iTRAQ quantitative proteomic analysis revealed the presence of differentially expressed proteins between the treatment and control groups.…”

Experimental Granulomatous Amebic Encephalitis Caused by Acanthamoeba castellanii

“…Much of the research that seeks to elucidate these aspects of GAE is carried out in vitro [13][14][15][16] whose conclusions cannot always be extrapolated to clinical situations. Work using animal models for experimental infections, which bring the results obtained closer to the natural process of 2 contagion, dissemination and infection [17], has essentially been carried out with mice [18][19][20][21][22], while rats and other laboratory animals are rarely used.…”

A history of over 40 years of potentially pathogenic free-living amoeba studies in Brazil - a systematic review

“… 40 Proteomics and metabolomics analysis are also represented by studies devoted to characterising Acanthamoeba , which provided informative molecular elements with the potential to be investigated as drug targets or as epitopes for antibodies in diagnostic tools. 41 , 42 , 43 Additional targets for detection purposes are cation:proton antiporter protein family (CPA) and a calreticulin extracellular domain. 44 , 45 The former was identified through the monoclonal antibody mAb3, which positively reacted with several Acanthamoeba pathogenic strains.…”