TMEM37 and infection: The role of the first discovered PR1 as an antimicrobial protein is based on two pieces of evidence: purified PR1 inhibits the growth of bacterial, fungal, and oomycete pathogens in vitro and PR1 overexpression in plants suppresses pathogen infection (Alexander et al, 1993; Niderman et al, 1995; Rauscher et al, 1999).