Killer Yeast as a Novel Tool in Biotechnology: Advances in Targeted Antimicrobial Strategies
Abstract
Killer yeasts, a distinct group of yeast strains capable of secreting extracellular proteinaceous toxins lethal to susceptible microorganisms, have emerged as promising biotechnological tools for developing targeted antimicrobial strategies. These killer toxins act through specific mechanisms—such as inhibition of β-glucan synthesis, disruption of membrane integrity, or interference with vital metabolic pathways—thereby enabling the selective elimination of pathogenic fungi and certain bacteria while preserving beneficial microbiota. These toxins, often referred to as killer toxins, act through highly specific mechanisms-such as disrupting cell wall synthesis, impairing membrane integrity, or inhibiting essential metabolic pathways-allowing for the selective elimination of pathogenic fungi and certain bacteria. Engineered killer yeasts have demonstrated promising applications across multiple sectors, including food preservation, where they can prevent spoilage caused by fungal contamination; agriculture, where they can function as biological control agents against plant pathogens; and clinical settings, where they may provide alternative or adjunct therapies for antifungal-resistant infections. Additionally, killer yeast strains can be integrated into biofilm management strategies, disrupting microbial communities that are otherwise resistant to chemical disinfectants. Despite their potential, several challenges remain in translating killer yeast technology to large-scale and real-world applications. These include ensuring consistent toxin production under industrial conditions, assessing long-term ecological impacts, navigating regulatory frameworks, and addressing potential resistance development in target populations. Continued interdisciplinary research combining microbiology, biotechnology, and systems biology is essential to fully harness the potential of killer yeast in targeted antimicrobial interventions. This high specificity offers an advantage over conventional broad-spectrum antimicrobials, which often induce resistance and disrupt microbial balance. This review consolidates current progress and emerging insights, emphasizing both the opportunities and the constraints of killer yeast technology as a next-generation, precision-oriented antimicrobial platform aligned with sustainable biotechnology and the One Health approach.
Keywords
Killer Yeasts, Killer Toxins, Antifungal Resistance, Biocontrol, Biotechnology, Food Safety
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