Interference of Malassezia restricta in the Invasion of Staphylococcus aureus into Human Keratinocytes

Interference of Malassezia restricta in the Invasion of Staphylococcus aureus into Human Keratinocytes

Juan Yang1, Ivan Brilian2, Kwanwoo Shin2, Yunmi Lee3, Soojin Jang3, Kui Young Park4, and Won Hee Jung1

1Department of Systems Biotechnology, Chung-Ang University, Anseong 17546, Korea 

2Department of Chemistry and Institute of Biological Interfaces, Sogang University, Seoul 04107, Korea

3Antimicrobial Resistance Laboratory, Institut Pasteur Korea, Seongnam-si 13488, Korea

4Department of Dermatology, Chung‑Ang University Hospital, Seoul 06973, Korea

Abstract

The human skin serves as a crucial defense system, protecting against external stressors and hosting a diverse array of microorganisms that impact skin health and disease. Of particular interest is the polymicrobial interaction in the skin, as it can significantly influence the alteration of virulence traits and host immune responses. This study aims to investigate the influence of Malassezia restricta, a dominant fungal species on human skin, on the virulence of Staphylococcus aureus, a prominent skin bacterium associated with atopic dermatitis. Our findings revealed that M. restricta effectively interferes with the invasion of S. aureus into human keratinocytes, suggesting a potential mechanism for regulating bacterial infection by the fungus. Additionally, we observed that M. restricta exhibits binding capabilities to fibronectin, a key mediator of S. aureus invasion in keratinocytes. Physicochemical analysis indicated the involvement of a heat-unstable component, likely a protein produced by M. restricta, which necessitates physical contact between the fungus and keratinocytes for fibronectin binding. Collectively, our results shed light on the influential role of M. restricta in the pathogenesis of S. aureus and reveal a novel aspect of this fungal species within the human skin microbial community.