Proposal Defense – Neetika

About the event

Speaker: Neetika

Group: Dr. ChulHee Kang

Title: Investigating Molecular Interactions among Enzymes of Sorghum bicolor in Biosynthetic Pathways

Abstract:

Sorghum bicolor is a resilient crop widely cultivated for its adaptability to environmental stress and its richness in secondary metabolites, making it a promising candidate for sustainable development. The biosynthesis of these metabolites arises from two interconnected metabolic routes: flavonoid and monolignol pathways, which share intermediates and are believed to form dynamic multi-enzyme assemblies, known as metabolons around membrane-bound P450 enzymes. Understanding how enzymes interact within these pathways and coordinate their activities is important for optimizing carbon flux and enhancing metabolic efficiency. This proposal aims to investigate the static and dynamic interactions among enzymes in monolignol and flavonoid pathways and to determine how metabolon formation influences catalytic function. Objective 1 focuses on characterizing the structural and functional interactions among Chalcone Synthase (CHS), Chalcone Isomerase (CHI), and Chalcone Isomerase-Like (CHIL) proteins to uncover their cooperative roles in the early steps of flavonoid biosynthesis. Objective 2 will examine the dynamic assembly and organization of downstream flavonoid enzymes into metabolons that facilitate efficient substrate channeling and pathway regulation. Objective 3 will investigate the functional relationships among 4-Coumarate: CoA Ligase (4CL), Cinnamate 4-Hydroxylase (C4H), and Cytochrome P450 Reductase (CPR), key enzymes that connect the monolignol and flavonoid pathways. Using an integrated approach that combines macromolecular crystallography, fluorescence resonance energy transfer (FRET), dynamic and static light scattering (DLS/SLS), and isothermal titration calorimetry (ITC), this research aims to provide new insights into how multienzyme complexes form and are regulated in plant metabolic pathways.