His research focus has been environmental microbiology, microbial pathogenesis and vaccine development, and microbial biotechnology, mostly involving genetic approaches. His group developed one of the first “biosafety” strains of bacteria, Pseudomonas putida strain KT2440, for genetic engineering, and a large range of genetic tools for this metabolically versatile bacterium, which has become a major workhorse for biotechnological applications, and the P4SP chassis.