Evaluation of the functional activity of enzymes involved in the metabolism of sialic acids in different diets

• Grant number: 23/17650-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2024
• End date: February 28, 2025
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Lívia Soares Zaramela
• Grantee: Maria Laura Monteiro de Oliveira
• 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

Sialic acids (Sias) are monosaccharides composed of nine carbons and are mostly present on the cell surface of vertebrates. Among them, N-acetyl neuraminic acid (Neu5Ac) and N-glycolyl neuraminic acid (Neu5Gc) are the most abundant in mammals. These sugars are involved in several essential processes in human development, for example, making these molecules suitable for carrying information for glycan-protein, cell-cell, and pathogen-host recognition.Many bacteria have several enzymes specialized in the metabolism of sialic acids, notably sialidases and sialyltransferases. Through sialidases, microorganisms are able to cleave the bonds of Sias to their conjugates, thus being able to, with it free, use it as a source of energy (carbon), or even express it on its surface to mimic the host cell, evading of the immune response and conferring greater virulence to the pathogen. It is already known in the literature that enzymes, such as sialidases and sialitransferases, may present preferential activity towards different sialic acids. These preferences can help us understand the mechanisms used by commensal and pathogenic bacteria in interacting with their hosts.In this project we will evaluate the preferential activity of sialidase and sialitransferase enzymes from the microbiota of animals with different eating habits (herbivores, omnivores and carnivores). The discovery of new enzymes (sialidases and sialyltransfereases) with preferences for different sialic acids (Neu5Ac or Neu5Gc) will not only allow for a better understanding of the mechanisms of bacterial and host interaction, but is also of great interest for human health.