Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2021

Erindi/veggspjald / Talk/poster V48

Identification of weak allosteric regulators for glucose phosphate isomerase and their effects on metabolic flux rates

Höfundar / Authors: Yiming Yang Jónatansdóttir, Jens G. Hjörleifsson

Starfsvettvangur / Affiliations: Raunvísindastofnun HÍ

Kynnir / Presenter: Yiming Yang Jónatansdóttir

Enzyme allostery is a dynamic and intricate regulatory mechanism that plays a critical role in modulating intracellular fluxes to maintain cell homeostasis and metabolic fitness under various perturbations. The concept of allostery has evolved considerably in the past decades, from the classical models encompassing ligand induced conformational changes to the dynamic conformation ensembles and population shift model. Along with a broadened perspective on allostery, the advent of high-throughput technologies has boosted the discovery of allosteric targets and novel modulators with potential therapeutic applications. In theory, all dynamic proteins are weakly allosteric, including those who have previously been termed non-allosteric, that is if the redistribution of protein conformational states upon ligand binding underlies the allosteric behavior. Furthermore, the effect of week allosteric regulation in the µM to mM range of metabolites is still largely unexplored for many metabolic pathways. A relative few number of biophysical approaches provide means for the screening of weak binding event (>100 µM), and most are of low-throughput nature. Also, high-throughput enzymatic assays have proven to not be as reliably for screening as binding assays. Here, we focus on a highly sensitive binding method to detect weak binding events from metabolite libraries on several homodimeric glycolytic enzymes, previously termed non-allosteric, using the microscale thermophoresis (MST) method, and subsequent validation using enzymatic assays. Our focus will be on glucose phosphate isomerase (GPI), using novel direct approaches (contrary to the common coupled enzyme assays) to study kinetics of such isomerases in order to study the effect of weak molecular binding of metabolites on regulation of metabolic pathways.