Fig. 1.

Mechanisms of MDP intracellular delivery. a Extracellular MDP can permeabilize the host cell through membrane receptors such as hPepT1 and Pennexin-1. b Extracellular MDP can also be transported into the host cell by clathrin- and dynamin-dependent endocytic pathways. c Moreover, MDP can be derived from bacteria by the intracellular phagocytic cleavage. d Finally, MDP can additionally be released to the cytosol through autolysis of internalized of invasive bacteria