Definition of the Extracellular Proteome of Pathogenic-PhaseHistoplasma capsulatum
| Autor: | Chad A. Rappleye, Eric D. Holbrook, Jessica A. Edwards, Brian H. Youseff |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Proteome
Histoplasma Virulence macrophage complex mixtures Biochemistry Article Microbiology Fungal Proteins 03 medical and health sciences fluids and secretions Tandem Mass Spectrometry Extracellular Animals Macrophage dimorphism Pathogen 030304 developmental biology 0303 health sciences Fungal protein fungal pathogenesis biology 030306 microbiology General Chemistry bacterial infections and mycoses biology.organism_classification Yeast virulence secretome Host-Pathogen Interactions RNA Interference Chromatography Liquid |
| Zdroj: | Journal of Proteome Research |
| ISSN: | 1535-3907 1535-3893 |
| DOI: | 10.1021/pr1011697 |
| Popis: | The dimorphic fungal pathogen Histoplasma capsulatum causes respiratory and systemic disease. Within the mammalian host, pathogenic Histoplasma yeast infect, replicate within, and ultimately kill host phagocytes. Surprisingly, few factors have been identified that contribute to Histoplasma virulence. To address this deficiency, we have defined the constituents of the extracellular proteome using LC−MS/MS analysis of the proteins in pathogenic-phase culture filtrates of Histoplasma. In addition to secreted Cbp1, the extracellular proteome of pathogenic Histoplasma yeast consists of 33 deduced proteins. The proteins include glycanases, extracellular enzymes related to oxidative stress defense, dehydrogenase enzymes, chaperone-like factors, and five novel culture filtrate proteins (Cfp’s). For independent verification of proteomics-derived identities, we employed RNA interference (RNAi)-based depletion of candidate factors and showed loss of specific proteins from the cell-free culture filtrate. Quantitative RT-PCR revealed the expression of 10 of the extracellular factors was particularly enriched in pathogenic yeast cells as compared to nonpathogenic Histoplasma mycelia, suggesting that these proteins are linked to Histoplasma pathogenesis. In addition, Histoplasma yeast express these factors within macrophages and during infection of murine lungs. As extracellular proteins are positioned at the interface between host and pathogen, the definition of the pathogenic-phase extracellular proteome provides a foundation for the molecular dissection of how Histoplasma alters the host-pathogen interaction to its advantage. The extracellular proteome was defined for pathogenic-phase Histoplasma capsulatum through LC−MS/MS analysis of Histoplasma yeast culture filtrates and mass spectrometry of individual pathogenic-phase protein bands. The major extracellular proteins constituting the proteome include glycanases, oxidative stress proteins and five novel proteins. Ten proteins are preferentially expressed in the pathogenic phase of which nine are expressed during infection, suggesting that they contribute to Histoplasma pathogenesis. |
| Databáze: | OpenAIRE |
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