Alexander "Sandy" D. Johnson is an American biochemist and Professor and Vice Chair of the Department of Microbiology and Immunology at the University of California, San Francisco.
[3] Johnson then moved on to a Ph.D. at Harvard University with Mark Ptashne working on the role of the Cro protein in regulating the phage lytic cycle.
[3] In 1981, Johnson moved to the University of California, San Francisco to work as a postdoctoral fellow in the laboratory of Ira Herskowitz, working on gene regulation in the model yeast Saccharomyces cerevisiae.
[4] Alexander Johnson is known for his work on gene regulation and cell biology in the yeast Candida albicans.
[3] His group has also investigated genes that allow C. albicans to survive and replicate inside mammalian hosts.