Application of Proteomics in the Investigation of Morphogenesis in Wangiella Dermatitidis

Abstract

Wangiella dermatitidis is a melanized, pathogenic, polymorphic fungus that in vitro grows primarily in a yeast form, but is capable of morphological changes resulting in growth as either hyphae (filaments) or swollen, multicellular bodies. The latter morphology strongly resembles the in vivo form of tissues infected with W. dermatitidis and other closely-related fungi. Each of these three morphologies can be readily induced through varying growth conditions of the wild-type strain or by culture of developmental mutants. Of particular interest is the conversion of the yeast phase to the multicellular growth form, which is the focus of the present study. Whole-cell, protein profiles of the wild-type strain and the temperature-sensitive mutant, Mc3, were developed following incubation at both 25⁰C and 37⁰C (body temperature). At both temperatures, the wild type grew as yeast cells, whereas strain Mc3 also grew as a yeast at 25⁰C, but formed the multicellular growth form at 37⁰C. Protein profiles showed consistency in landmark proteins found within all four study groups, as well as temperature dependent and strain dependent proteins. Fifty protein spots were excised and sequenced by capillary-liquid chromatography-nanospray tandem mass spectrometry. A Mascot search of established databases revealed putative identities of these proteins. The identified proteins included: heat shock protein 60 mitochondrial precursor, NADP-dependent mannitol dehydrogenase, and copper-zinc superoxide dismutase (Cu-Zn SOD). The results presented in this study indicate the relevance of proteomics as a tool in interpreting the morphological and physiological conditions of phase changes exhibited by W. dermatitidis.