Physical Organic Chemistry in Biochemical Toxicology and the Career of Robert P. “Bob” Hanzlik

The career of Robert Hanzlik had a dramatic impact on the application of physical organic chemistry to the field of biochemical toxicology. Publications that came out of the Hanzlik laboratory helped to establish and broaden the exploration of physical organic chemistry in biochemical toxicology. Bob expertly employed model compounds and systems to probe and explore various facets of the chemistries resulting in toxic insults. His lab examined mechanisms of formation of reactive metabolites in detail. Bob engaged a range of approaches in support of these studies including synthetic chemistry, radiolabeled tracers, analytical chemistry, biochemistry and spectroscopy (including high field NMR and mass spectrometry). Bob applied these approaches to in vitro and in vivo studies of importance to model toxins. In the latter part of his career, he published extensively on characterization of protein adducts of reactive metabolites. This led him to work in bioinformatics of metabolic activation studies and filling and mining reactive metabolite target protein databases. Bob entered new areas of research with gusto. It was a hallmark of his career and that of his students. His work had broad applications to chemicals and drugs. He laid the groundwork for many future studies. Below, I trace his research areas over the years and the involvement of physical organic chemistry therein.