PARP1 and cancer: In addition, M. fermentans DnaK, a chaperone protein belonging to the HSP70 family, can be taken-up by uninfected cells, and upon infection, localizes in different cellular compartments including the nucleus, where it interacts with poly (ADP-ribose) polymerase 1 (PARP1) and p53, thereby reducing DNA repair activities and anti-cancer responses (Zella et al., 2018; Benedetti et al., 2020).