Editing Candida: Origins and Advances of CRISPR Tools

Pathogens causing candidiasis encompass a diverse group of ascomycetous yeasts that have become essential models for studying fungal adaptability, pathogenicity, and host-pathogen interactions. Although many candidiasis-promoting species exist as commensals within host microbiota, several have acquired virulence traits that enable opportunistic infections, positioning them as a leading cause of invasive fungal disease in humans. Deciphering the molecular and genetic determinants that underpin the biology of organisms responsible for candidiasis has long been a central objective in medical and molecular mycology. However, research progress has been constrained by intrinsic biological challenges, including noncanonical codon usage and the absence of a complete sexual cycle in diploid species, which have complicated traditional genetic manipulation. CRISPR-Cas9 genome editing has overcome many of these limitations, providing a precise, efficient, and versatile framework for targeted genomic modification. This system has facilitated functional genomic studies ranging from single-gene deletions to high-throughput mutagenesis, yielding new insights into the mechanisms governing virulence, antifungal resistance, and stress adaptation. Since its initial application in Candida albicans, CRISPR-Cas9 technology has been refined and adapted for other clinically and industrially relevant species, including Nakaseomyces glabratus (formerly referred to as Candida glabrata), Candida parapsilosis, and Candida auris. The present work provides an overview of the evolution of genetic approaches employed in research directed against candidiasis-associated species, with a particular focus on the development and optimization of CRISPR-based systems. It highlights how recent advancements have improved the genetic tractability of these pathogens and outlines emerging opportunities for both fundamental and applied studies in fungal biology.