Crystallographic Cryoenzymology and the Legacy of Tony Fink

During the past thirty years significant contributions to our understanding of the structural origins of the catalytic power of enzymes have come from solution and crystallographic studies of enzyme-substrate and enzymeintermediate complexes trapped at subzero temperatures, a field that was pioneered in large part by Anthony L. Fink and Pierre Douzou. Here I review, from a personal perspective, the history of crystallographic cryoenzymology, with an emphasis on the contributions of Tony Fink. The story has a moral: if you choose your collaborators based not only on their scientific prowess but also on their human qualities, the resulting friendships will enrich your life.