title: Irreversible block of the mycelial-to-yeast phase transition of Histoplasma capsulatum.
abstract: p-Chloromercuriphenylsulfonic acid (PCMS), a sulfhydryl inhibitor, prevented the mycelial-to-yeast transition of the dimorphic fungal pathogen, Histoplasma capsulatum. The effect of PCMS was specific for the mycelial-to-yeast transformation; it had no effect on growth of either the yeast or mycelial forms or on the yeast-to-mycelial transition. The failure of PCMS-treated mycelia to transform to yeast was permanent and irreversible. PCMS-treated mycelia could not infect mice but could stimulate resistance to infection by a pathogenic strain of Histoplasma capsulatum. These results suggest a new general strategy for vaccine development in diseases caused by dimorphic pathogens.
mesh_terms: D002731:4-Chloromercuribenzenesulfonate / Q000494:pharmacology; D000818:Animals; D003580:Cytochromes / Q000378:metabolism; D004734:Energy Metabolism / Q000187:drug effects; D005656:Fungal Proteins / Q000096:biosynthesis; D006658:Histoplasma / Q000187:drug effects / Q000472:pathogenicity / Q000502:physiology*; D006660:Histoplasmosis / Q000209:etiology; D007700:Kinetics; D051379:Mice; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010101:Oxygen Consumption / Q000187:drug effects
chemical_list: D003580:Cytochromes; D005656:Fungal Proteins; D002731:4-Chloromercuribenzenesulfonate