Fungal-bacterial interactions: In health and disease

Abstract

Fungi and bacteria have long shared ecological niches and engaged in a spectrum of relationships ranging from synergistic to antagonistic to enhance survival or gain competitive advantages. Importantly, there is growing evidence that polymicrobial interactions involving Candida and bacteria may synergize their pathogenic potential by enhancing colonization in the host and contributing to recalcitrance to antimicrobial treatment. Increasing number of microbiome studies has enabled us to develop a greater understanding of how microbial interactions influence various aspects of host physiology and disease outcomes. However, studies exploring the influence of candidal populations on the composition of host bacterial microbiota have been lacking highlighting the importance of a dual approach to microbiome analysis. This chapter aims to appraise the clinical importance of the interactions between C. albicans and bacteria occupying the same sites in their human host, focusing on the most common infections from which Candida is co-isolated with various bacterial species. Specifically, emphasis is placed on quorum sensing, the complex system of cell-to-cell communication based on secreted molecules that govern behavior of cell populations. Understanding the physical and molecular interactions between Candida and bacteria will greatly aid in developing novel therapeutic strategies such as blocking of adhesion receptors or interrupting communications via targeting quorum sensing molecules. Therefore, in depth investigations are warranted to provide crucial insights into clinically relevant interactions between Candida and bacteria, which can be exploited for the benefit of mankind.