Assistant Professor, Biochemistry

B.A., Reed College

Ph.D., Stanford University

All cellular life is defined by membranes. At the edge of the cell, the plasma membrane forms a barrier against external insults, and internally, organellar membranes compartmentalize crucial cellular processes. Proteins embedded within membranes allow for the regulated passage of biomolecules and communication within and between cells. As a result, membranes are a focal point of immune signaling pathways and a chief target of pathogens that seek to destroy cells. Alex Johnson discovered that an immune signaling mechanism used by human cells is billions of years older than expected and deployed by bacteria to defend against their major pathogens, bacteriophages. In cells, this mechanism relies on an incredible class of proteins that form gigantic pores in membranes, effectively “poking holes” that induce cell death and the secretion of immune signaling molecules. By studying bacterial homologs of these pore-forming proteins, Johnson’s work established a new frame of reference to understand how these proteins work and yielded unforeseen insights into their mechanism of regulation in human cells. The broad goal of his lab’s research program is to answer stubborn problems of immunology using a comparative evolutionary analysis. Currently, the lab of Microbes and Biochemistry at Brandeis University is focused on applying a pan-species analysis to reveal the full breadth of mechanisms used by pore-forming proteins and applying this knowledge to develop pore-forming proteins as a new therapeutic modality.