This entry represents the N-terminal domain of the antitoxin component Xre of a type II toxin-antitoxin (TA) system, which is the helix-turn-helix (HTH) DNA binding domain, structurally similar to the Cro repressor, therefore, also referred to as HTH/Cro-like DNA-binding domain [2]. This domain is also found in other antitoxin components, associated with a C-terminal toxin-binding domain Pfam:PF09722 [1,2].

1: An NAD(+) Phosphorylase Toxin Triggers Mycobacterium tuberculosis Cell Death. Freire DM, Gutierrez C, Garza-Garcia A, Grabowska AD, Sala AJ, Ariyachaokun K, Panikova T, Beckham KSH, Colom A, Pogenberg V, Cianci M, Tuukkanen A, Boudehen YM, Peixoto A, Botella L, Svergun DI, Schnappinger D, Schneider TR, Genevaux P, de Carvalho LPS, Wilmanns M, Parret AHA, Neyrolles O; Mol Cell. 2019;73:1282-1291. PMID:30792174

2: The RES domain toxins of RES-Xre toxin-antitoxin modules induce cell stasis by degrading NAD+. Skjerning RB, Senissar M, Winther KS, Gerdes K, Brodersen DE; Mol Microbiol. 2019;111:221-236. PMID:30315706