AUTHOR=Short Bryn , Delaney Christopher , McKloud Emily , Brown Jason L. , Kean Ryan , Litherland Gary J. , Williams Craig , Martin S. Lorraine , MacKay William G. , Ramage Gordon 

TITLE=Investigating the Transcriptome of Candida albicans in a Dual-Species Staphylococcus aureus Biofilm Model

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=11

YEAR=2021

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2021.791523

DOI=10.3389/fcimb.2021.791523

ISSN=2235-2988

ABSTRACT=<p><italic>Candida albicans</italic> is an opportunistic pathogen found throughout multiple body sites and is frequently co-isolated from infections of the respiratory tract and oral cavity with <italic>Staphylococcus aureus.</italic> Herein we present the first report of the effects that <italic>S. aureus</italic> elicits on the <italic>C. albicans</italic> transcriptome. Dual-species biofilms containing <italic>S. aureus</italic> and <italic>C. albicans</italic> mutants defective in <italic>ALS3</italic> or <italic>ECE1</italic> were optimised and characterised, followed by transcriptional profiling of <italic>C. albicans</italic> by RNA-sequencing (RNA-seq). Altered phenotypes in <italic>C. albicans</italic> mutants revealed specific interaction profiles between fungus and bacteria. The major adhesion and virulence proteins Als3 and Ece1, respectively, were found to have substantial effects on the <italic>Candida</italic> transcriptome in early and mature biofilms. Despite this, deletion of <italic>ECE1</italic> did not adversely affect biofilm formation or the ability of <italic>S. aureus</italic> to interact with <italic>C. albicans</italic> hyphae. Upregulated genes in dual-species biofilms corresponded to multiple gene ontology terms, including those attributed to virulence, biofilm formation and protein binding such as <italic>ACE2</italic> and multiple heat-shock protein genes. This shows that <italic>S. aureus</italic> pushes <italic>C. albicans</italic> towards a more virulent genotype, helping us to understand the driving forces behind the increased severity of <italic>C. albicans</italic>-<italic>S. aureus</italic> infections.</p>