RUI: Atomic Level Mechanism of NIS Synthetases

California Lutheran University, Thousand Oaks CA

Investigators

Abstract

With the support of the Chemistry of Life Processes (CLP) Program in the Division of Chemistry, Dr. Katherine Hoffmann at California Lutheran University will study the mechanism of a class of enzymes that biosynthesize iron-binding molecules essential for the survival of bacteria and fungi. The enzymes being studied (non-ribosomal peptide synthetase-independent siderophore synthetases, or NIS-synthetases) make molecules called siderophores, which help microorganisms scavenge iron nutrients from the environment. This foundational research exploring the biochemical mechanism of NIS synthetases advances the understanding of an important mechanism by which bacteria evade the immune defense system of an infected host and, thus, holds potential to inform strategies to combat bacterial infections. The project engages undergraduate students in all aspects of the research—from multidisciplinary laboratory work to conference presentations—offering them valuable scientific training and helping prepare the next generation of contributors to academia and industry. The objective of this project is to elucidate the biochemical mechanism of NIS synthetases—an enzyme class implicated in bacterial virulence. The novelty of this work lies not only in the unexplored enzymatic mechanism of NIS synthetases, but also their distinct conformational folds and chemistries. Specifically, the project addresses questions of what role does a proposed catalytic triad play in the active sites of these enzymes, how does proton transfer contribute to the mechanism, and what role the product binding pocket plays in enzyme turn-over. This multidisciplinary study integrates liquid-chromatography mass spectrometry, molecular biology techniques, kinetic analyses, spectroscopy, and structural biology to define the atomic and molecular dynamics underpinning enzyme activity. The research will be conducted exclusively with undergraduate scientists, affording them rigorous training and scholarly involvement through experimental work, conference participation, and co-authorship opportunities, thereby fostering a pipeline of skilled researchers equipped for careers in industry or advanced academic study. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.