Prospecting for bioactive substances in microorganisms recovered from Caves of the Alto Ribeira Tourist State Park (São Paulo, Brasil)

• Grant number: 24/22326-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: July 01, 2025
• End date: June 30, 2026
• Field of knowledge: Biological Sciences - Pharmacology - Biochemical and Molecular Pharmacology
• Principal Investigator: Leticia Veras Costa Lotufo
• Grantee: Beatriz Elena Salgado Rivero
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Caves are unique and unexplored ecosystems, with extreme conditions that limit the distribution of fauna and flora, such as total absence or low level of light, low temperature and high humidity, in addition to low nutrient content. In this adverse environment, microorganisms, which present an unexpected high diversity, play an important role in the cycling of nutrients and organic matter, determining the geomorphology of these ecosystems. In addition to this intrinsically ecological role, microorganisms, especially actinomycetes, are prolific producers of substances with unique chemical structures and recognized pharmacological potential, and this also seems to be true for those living in caves. In this sense, this study focuses on prospecting for bacteria from cave vermiculations, which may offer new secondary metabolites with therapeutic potential. Vermiculations are common formations on the rock surfaces of caves around the world, and are characterized by variable morphologies, colors and dimensions, and are generally composed of calcite, associated with quartz, and traces of clay minerals. From this matrix, the aim is to isolate colonies of cultivable bacteria and produce biological extracts from these strains. These extracts will be subjected to cytotoxicity tests against tumor cells, as well as tests to evaluate antibiotic activity. Furthermore, the extracts will be analyzed using liquid and gas chromatography techniques coupled to mass spectrometry (LC-MS and GC-MS) to describe a chemical profile of the extracts produced. The molecular identification of the bacteria will be done by sequencing the 16S rRNA gene. It is expected that this study will result in the isolation of new species of bacteria capable of producing bioactive substances, in addition to contributing to the knowledge of the microbiota of Brazilian caves. The project also aims to develop a database of microorganisms from Brazilian caves and promote environmental conservation of these unique ecosystems. (AU)