The role of sialic acids in the interaction between Cutibacterium acnes, Staphylococcus aureus and keratinocytes: a co-culture model for cross-feeding study

• Grant number: 24/22238-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2025
• End date: February 28, 2026
• Field of knowledge: Biological Sciences - Biochemistry - Biochemistry of Microorganisms
• Principal Investigator: Lívia Soares Zaramela
• Grantee: Isabela Mariano Cardoso
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Atopic dermatitis is an inflammation caused by skin dysbiosis. Patients with this condition frequently show a high prevalence of the pathogenic bacterium Staphylococcus aureus. It is also known that microorganisms in the microbiota establish complex ecological relationships among themselves. One of these relationships is the cross-feeding mechanism between commensal microorganisms and S. aureus.Sialic acids are glycans found on the surface of some cells. They play essential roles in cell-cell and cell-host recognition. In addition, several bacteria possess specialized enzymes for the metabolism of these sialic acids. As a result, these carbohydrates are cleaved from their conjugates and can be used as a source of energy (carbon).In this scientific initiation project, we will study the role of cross-feeding between C. acnes and S. aureus involving sialic acids in immortalized human keratinocyte cells, HaCaT. The objective is to evaluate whether C. acnes, through its sialidases, can release host-derived sialic acids that will be metabolized by S. aureus, a species deficient in this enzyme. Understanding this cross-feeding mechanism will provide new insights into microbial interactions and enable the development of future therapeutic interventions.