Standardization of MALDI - TOF mass spectrometry for identification of Malassezia spp. strains.

• Grant number: 25/15292-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Maria da Gloria Sousa Stafocker
• Grantee: Milena de Melo Scarano Coelho
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Fungi cause diseases that affect more than one billion people worldwide, resulting in approximately 1.5 million deaths annually. However, fungal diseases continue to be a neglected issue by public health authorities, despite the fact that most fungal deaths are preventable. Among the fungi of clinical importance, the genus Malassezia stands out, representing approximately 80% of the fungal species of human skin. It is the most prevalent fungal commensal of the skin, especially in lipid-rich areas, and its dysregulation is associated with several inflammatory dermatoses. In addition, recent studies indicate the involvement of Malassezia in systemic conditions, such as inflammatory bowel diseases and even neurological pathologies, increasing scientific and clinical interest in the genus. Conventional morphological identification is not capable of discriminating against the species of Malassezia spp and DNA sequencing is an expensive technique that is poorly adapted to clinical laboratories. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI - TOF) is a rapid and accurate methodology for identifying microorganisms, including filamentous fungi and yeasts of clinical importance. However, there are few studies on the identification of Malassezia spp species using the MALDI - TOF methodology, with controversial results depending on the methodology and equipment used. Thus, this work aims to standardize the identification of Malassezia species using the Biotyper platform (Bruker) and to build an in-house database that allows the characterization of the species and, after validation, can be made available to the medical and scientific community