Establishment of synthetic microbial communities to study cooperation or competition between pathogenic and commensal bacteria in the presence of sialic acids

• Grant number: 24/03785-3
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2024
• End date: March 31, 2026
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Lívia Soares Zaramela
• Grantee: João Vitor Wagner Ordine
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 20/08554-9 - Establishment of an experimental and computational platform to study host-microbes interactions promoted by sialic acids, AP.JP

Abstract

Microbial communities are complex and dynamic, thus, the integrated use of computational and experimental tools is necessary to understand the systemic function of each member. However, mapping the multiple interactions between members of microbial communities and their hosts is a highly complex task. Therefore, synthetic microbial communities are abstractions of natural systems that allow the in-depth study and analysis of fundamental processes taking place in microbial communities. When it comes to the human skin microbiota, recent studies have shown the cooperative role of the bacterium Cutibacterium acnes in Staphylococcus aureus colonization and growth, with the latter being directly associated with several human diseases, such as atopic dermatitis, for instance. Interestingly, both microorganisms appear to complement themselves genetically: the former codes for secreted sialidases (responsible for releasing sialic acids from membrane-linked glycoconjugates) and is highly abundant in human skin, while the latter, despite having all the genes required for sialic acid catabolism, doesn't code for sialidases and is dependent on those from other organisms. Therefore, we aimed to establish a synthetic microbial community to study the cooperation or competition between the pathogenic S. aureus and the commensal bacteria C. acnes in the presence of sialic acids. To this end, optimal cultivation conditions - both for isolated bacteria and in co-culture - will be optimized and the growth performance of each isolate will be evaluated in the presence and absence of sialic acids, which will be accompanied by analysis of the gene expression of genes involved in the sialic acid metabolism.