[3] An important collaborator and member of his laboratory at Stanford University was biochemist Alice del Campillo Campbell, his wife.
During the summers he spent time with Gio ("Joe") Bertani at Caltech and the University of Southern California, at Cold Spring Harbor Laboratory and at the Institut Pasteur with François Jacob.
[6] The two worked closely together throughout their careers, investigating research questions such as the encoding of heat-sensitive endolysin and the biosynthesis and regulation of biotin.
[1][3] Campbell spent the next nine years on the faculty of the University of Rochester, where he made significant discoveries about lambda phage.
Campbell's research was focused on a specific bacterial virus, phage lambda, and its host bacterium E. coli,[11] but the model provided insights into how extrachromosomal DNA can be inserted and excised in other organisms.
[14] While study of the regulation of integration and excision of phage lambda in E coli has been a primary focus of his research, Campbell and research associates also studied regulation and expression of E coli genes linked to the lambda insertion location, including the biotin (bio) and galactose (gal) genes.
[11] Early studies on bacterial viruses began after the discovery by Twort and d’Herelle of ‘filterable agents’ which were able to destroy bacteria.