Variable Surface Display and Post‐Translational Regulation of the Fungal Adhesin Epa1p

Abstract

Infection by the fungal pathogen Candida glabrata is reliant on a collection of cell surface adhesins that play a variety of roles necessary for transmission, establishment, and cell proliferation. One particular adhesin, Epithelial Adhesin 1 (Epa1p), is responsible for binding to host tissue and biofilm formation, which is essential for fungal propagation. Epa1p structure consists of three domains: a C‐terminal GPI anchor for cell wall linkage, an N‐terminal intercellular binding domain responsible for epithelial cell binding, and a serine/threonine rich linker domain connecting these terminal domains. The linker domain contains a 40‐amino acid tandem repeat region which our lab has observed to be variable in repeat copy number between isolates from clinical sources. We expressed Epa1p with various repeat copy numbers in epa1Δ C. glabrata as well as in the related yeast, S. cerevisiae to determine how differences in repeat copy number affect Epa1p surface display and binding to human epithelial cells. Our initial data suggest that the processing of, as well as cell wall stability of, Epa1p is dependent upon the repeat copy number of Epa1p. We have also collected data, which suggest that Epa1p surface level is dependent on media growth conditions. Altogether our data demonstrate that Epa1p repeat copy number influences the properties of Epa1p and the adhesive characteristics of C. glabrata.Support or Funding Information1. Army Research Office grant W911NF16101752. Tufts Collaborates!3. 2018 ASBMB Undergraduate Research Award4. Tufts Summer ScholarsThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.