Microbe-metabolomic of endophytic and rhizosphere fungi from Senna spectabilis by nuclear magnetic resonance (NMR)

Abstract

The discovery of new bioactive molecules from natural sources has been decreasing over the years, mainly due to the identification of the main chemotypes, the challenges of a reductionist approach and the incorporation of combinatorial chemistry. To overcome this problem, the chemistry of natural products has targeted the use of new and unexplored natural matrixes, such as endophytic and rhizospheric microorganisms, aiming to discover biologically promising compounds and new chemotypes. To identify and quantify these metabolites in a complex matrix is often laborious and demanding, since compounds in a biological system range in chemical/physical properties, concentration and structure diversity. In this sense, dereplication strategies emerges as a rapid way of identifying known compounds in mixtures, minimizing time, effort, and cost, as well as identifying new promising chemotypes. In microbe metabolomics, several analytical and biological challenges are faced when dealing with structure elucidation. Major analytical obstacles regard matrix complexity and the elucidation of low abundance metabolites, while recent genomic studies demonstrates that only a fraction of gene clusters are active during conventional fungi fermentation, silencing many other gene clusters responsible for new secondary metabolites. The main goal of this work is to analyze the metabolic profiles of endophytic and rhizosphere fungi from Senna spectabilis (Fabaceae) aiming to identify novel metabolites and main chemotypes with significant biological importance. Specifically, we aim to integrate strategies applied to microbe metabolomics using one and two-dimensional nuclear magnetic resonance (NMR) of different nuclei by the development of algorithms that facilitate and accelerate dereplication processes as well as evaluate the distribution and diversity of metabolites under a given condition. Moreover, this project aims to integrate microbiological techniques, such as OSMAC and co-culture, maximizing metabolite diversity and production, generating a rational approach to study the chemical coexistence between microorganisms and their environment. (AU)