Time-lapse mesoscopy ofCandida albicansandStaphylococcus aureusdual-species biofilms reveals a structural role for the hyphae ofC. albicansin biofilm formation

Abstract

AbstractPolymicrobial infection withCandida albicansandStaphylococcus aureusmay result in a concomitant increase in virulence and resistance to antimicrobial drugs. This enhanced pathogenicity phenotype is mediated by numerous factors including metabolic processes and direct interaction ofS. aureuswithC. albicanshyphae. The overall structure of biofilms is known to contribute to their recalcitrance to treatment, however the dynamics of direct interaction between species and how it contributes to pathogenicity is poorly understood. To address this, a novel time-lapse mesoscopic optical imaging method was developed to enable the formation ofC. albicans/S. aureuswhole dual-species biofilms to be followed. It was found that yeast-form or hyphal-formC. albicansin the biofilm founder-population profoundly affects the structure of the biofilm as it matures. Different sub-populations ofC. albicansandS. aureusarise within each biofilm as a result of the differentC. albicansmorphotypes, resulting in distinct sub-regions. These data reveal thatC. albicanscell morphology is pivotal in the development of global biofilm architecture and the emergence of colony macrostructures and may temporally influence synergy in infection.