Joseph Mougous

Bacteria have been engaged in fierce competition with each other for at least three billion years. It is therefore not surprising that they have evolved a diverse array of sophisticated mechanisms for interbacterial antagonism. These pathways, and the countermeasures bacteria employ to defend themselves against them, are the focus of research in the Mougous Laboratory. Early on, we discovered that the type VI secretion system (T6SS) is widely employed by bacteria to deliver antibacterial toxins directly to contacting bacterial cells. We went on to identify and define the mechanisms employed by many of these toxins, to show that the Esx pathway plays a similar role in mediating toxin delivery in Gram-positive bacteria, and to demonstrate that both of these pathways are widespread in mammalian gut microbiomes. We have also investigated the role of T6SS effectors in bacterial pathogenesis, and have developed biotechnological applications of several antibacterial toxins, including harnessing a bacterial cytosine deaminase to produce the first mitochondrial genome base editor.

Current work in the Mougous lab focuses on: 1) identifying and characterizing new interbacterial antagonism pathways and toxins; 2) developing new biotechnological applications for our discoveries; 3) uncovering the molecular mechanisms by which epibiotic, parasitic bacteria interact with their bacterial hosts; 4) elucidating the role of interbacterial antagonism in the gut microbiome and 5) defining mechanisms by which bacteria defend themselves against antagonistic attacks.