After his postdoc positions, he joined the Scripps Research Institute in La Jolla, California, in 1982 as an assistant professor and is currently professor in the department of molecular biology and the Skaggs Institute for Chemical Biology. His laboratory focuses on the recognition of microbial pathogens by the immune system and has determined over 85 crystal structures of mouse, human, shark, and catalytic antibodies, with a variety of antigens, including steroids, peptides, carbohydrates and viral proteins, such as HIV-1 and Hepatitis C virus envelope glycoproteins.[5] His team was reported by the 6 February 2004 edition of Science magazine to have managed to synthesise the hemagglutininprotein responsible for the 1918 outbreak of Spanish flu.[6]
Since 2000, he has directed the Joint Center for Structural Genomics (JCSG) that has pioneered innovative new methods for high throughput structural studies, including x-ray and NMR. The JCSG has determined over 700 structures that focus on the expanding protein universe.[7]