Mode of Action of the Catalytic Site in the N-Terminal Ribosome-Inactivating Domain of JIP60.

Jasmonate-induced protein 60 (JIP60) is a ribosome-inactivating protein (RIP) from barley () and is involved in the plant immune response dependent on jasmonate hormones. Here, we demonstrate in that transient expression of the N-terminal domain of JIP60, from which the inhibitor domain (amino acids 163-185) is removed, initiates cell death, leading to extensive necrosis of leaf tissues. We used structure prediction of JIP60 to identify potential catalytic amino acids in the active site and tested these by mutagenesis and in planta assays of necrosis induction by expression in , as well as through an in vitro translation-inactivation assay.

RexAB is essential for the mutagenic repair of DNA damage caused by co-trimoxazole.

Co-trimoxazole (SXT) is a combination therapeutic that consists of sulfamethoxazole and trimethoprim that is increasingly used to treat skin and soft-tissue infections caused by methicillin-resistant (MRSA). However, the use of SXT is limited to the treatment of low-burden, superficial infections and its therapeutic value is compromised by the frequent emergence of resistance. As a first step towards the identification of approaches to enhance the efficacy of SXT, we examined the role of bacterial DNA repair in antibiotic susceptibility and mutagenesis.