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Integrated post-genomic cell wall analysis reveals floating biofilm formation associated with high expression of flocculins in the pathogen Candida krusei.

ABSTRACT: The pathogenic yeast Candida krusei is more distantly related to Candida albicans than clinically relevant CTG-clade Candida species. Its cell wall, a dynamic organelle that is the first point of interaction between pathogen and host, is relatively understudied, and its wall proteome remains unidentified to date. Here, we present an integrated study of the cell wall in C. krusei. Our comparative genomic studies and experimental data indicate that the general structure of the cell wall in C. krusei is similar to Saccharomyces cerevisiae and C. albicans and is comprised of b-1,3-glucan, b-1,6-glucan, chitin, and mannoproteins. However, some pronounced differences with C. albicans walls were observed, for instance, higher mannan and protein levels and altered protein mannosylation patterns. Further, despite absence of proteins with high sequence similarity to Candida adhesins, protein structure modeling identified eleven proteins with similarity to flocculins/adhesins in S. cerevisiae or C. albicans. To obtain a proteomic comparison of biofilm and planktonic cells, C. krusei cells were grown to exponential phase and in static 24-h cultures. Interestingly, the 24-h static cultures of C. krusei yielded formation of floating biofilm (flor) rather than adherence to polystyrene at the bottom. The proteomic analysis of both conditions identified a total of 32 cell wall proteins. In line with a possible role in flor formation, increased abundance of flocculins, in particular Flo110, was observed in the floating biofilm compared to exponential cells. This study is the first to provide a detailed description of the cell wall in C. krusei including its cell wall proteome, and paves the way for further investigations on the importance of flor formation and flocculins in the pathogenesis of C. krusei.

INSTRUMENT(S): timsTOF Pro

ORGANISM(S): Candida Krusei

SUBMITTER: Gertjan Kramer

PROVIDER: MSV000091793 | MassIVE | Tue Apr 25 10:34:00 BST 2023

SECONDARY ACCESSION(S): PXD041801

REPOSITORIES: MassIVE

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Integrated post-genomic cell wall analysis reveals floating biofilm formation associated with high expression of flocculins in the pathogen Candida krusei.

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