Jan-Ulrik Dahl is an Assistant Professor of Microbiology in the School of Biological Sciences at Illinois State University. He is a trained protein biochemist, who discovered two novel sulfur carrier proteins and characterized their role for molybdenum cofactor biosynthesis. While the majority of his work was biochemical in nature , he realized the necessity in validating results in an in vivo context. During internships at the CNRS in Marseille (France), he was trained in transcriptomics. Dr. Dahl received his postdoctoral training in Ursula Jakob’s lab at the University of Michigan, where used the genetic toolboxes available for E. coli and P. aeruginosa and deciphered novel bacterial stress response systems. Dr. Dahl's research identified an acid-activated chaperone with effective protein-protective properties under low pH conditions. He then focused on studying polyphosphate (polyP), an ancient and highly conserved inorganic biopolymer, and its unrecognized role as protein stabilizing scaffold which protects bacteria against a wide range of physiologically relevant protein-unfolding stress conditions. He also discovered the first inhibitor of prokaryotic polyP synthesis (i.e. the FDA-approved drug mesalamine) and demonstrated that inhibition of polyP synthesis by mesalamine decreases biofilm formation, stress resistance, and colonization. Since 2019, Dr. Dahl is now an Assistant Professor at Illinois State University, where he studies response and defense mechanisms to reactive oxygen and chlorine species in uropathogenic E. coli (UPEC) and P. aeruginosa.