Biological function and molecular mapping of M antigen in yeast phase of Histoplasma capsulatum.

ABSTRACT: Histoplasmosis, due to the intracellular fungus Histoplasma capsulatum, can be diagnosed by demonstrating the presence of antibodies specific to the immunodominant M antigen. However, the role of this protein in the pathogenesis of histoplasmosis has not been elucidated. We sought to structurally and immunologically characterize the protein, determine yeast cell surface expression, and confirm catalase activity. A 3D-rendering of the M antigen by homology modeling revealed that the structures and domains closely resemble characterized fungal catalases. We generated monoclonal antibodies (mAbs) to the protein and determined that the M antigen is present on the yeast cell surface and in cell wall/cell membrane preparations. Similarly, we found that the majority of catalase activity was in ex

SUBMITTER: Guimaraes AJ 

PROVIDER: S-EPMC2566600 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature