Glutathionylation, that is, the formation of mixed disulfides between protein cysteines and
glutathione (GSH) cysteines, is a reversible post-translational modification catalyzed by dierent
cellular oxidoreductases, by which the redox state of the cell modulates protein function. So far, most
studies on the identification of glutathionylated proteins have focused on cellular proteins, including
proteins involved in host response to infection, but there is a growing number of reports showing
that microbial proteins also undergo glutathionylation, with modification of their characteristics and
functions. In the present review, we highlight the signaling role of GSH through glutathionylation,
particularly focusing on microbial (viral and bacterial) glutathionylated proteins (GSSPs) and host
GSSPs involved in the immune/inflammatory response to infection; moreover, we discuss the
biological role of the process in microbial infections and related host responses