Structural determinations of the interactions between Hip1 and GroEL2 of M. tuberculosis and identification from their metabolic effects on host cells for prospecting inhibitors

• Grant number: 25/08276-2
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: September 01, 2025
• End date: February 28, 2030
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Raghuvir Krishnaswamy Arni
• Grantee: Peterson de Jesus Morais
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil
• Associated research grant: 20/08615-8 - Protein exosites, cryptic sites and moonlighting: identification, functional mapping and effects of changes in structure, AP.TEM

Abstract

Tuberculosis is an infectious disease caused by the bacterium Mycobacterium tuberculosis (MTB), responsible for high morbidity and mortality rates globally. There are antibiotics and vaccines, but these have limitations in terms of prevention, bacterial resistance and poor adherence to treatment. MTB infects different types of epithelial and immune system cells, such as dendritic cells and macrophages. Tuberculosis can cause severe problems such as irreparable lung damage and even death. There are virulence factors linked to its resistance, dissemination and modulation of the immune system, Hip1 being one of the main ones. This toxin is an atypical serine proteinase that has high specificity for cleaving the GroEL2 substrate, which is also a virulence factor produced by MTB. Hip1 directly affects the functioning of cells in the host's immune system, such as dendritic cells, inhibiting the production of cytokines that are fundamental to the inflammatory immune response. The interference of Hip1 in the production of these cytokines impairs the activation of macrophages, compromising the host's microbicidal responses. The chaperonin GroEL2, which is cleaved in its functional form by Hip1, plays a key role in the functioning of the pathogenic microorganism, acting as a helper in the proper folding of proteins expressed by MTB, as well as modulating the immune response. In view of the importance of Hip1 and GroEL2 in the virulence and survival of MTB, the present study aims to determine the structural interactions that trigger the Hip1-GroEL2 interaction, as well as to identify the metabolic pathways of the host cells of the immune system affected by these virulence factors, with a view to better targeting the development of highly specific peptide inhibitors to the molecular targets. To this end, a set of experimental and computational techniques, including phage display, enzymatic and inhibition assays, co-crystallization, metabolomics, docking and dynamics molecular, will be applied to achieve the objectives of this research project. (AU)