This domain is Tgi2PP found in Pseudomonas protegens. Tgi2PP is part of the Tge2PP- Tgi2PP Effector-immunity pair secreted by the type VI secretion system (T6SS). Tgi2PP interacts predominantly by hydrogen bonding and hydrophobic interactions with Tge2PP via the insertion of the beta-sheet core of Tgi2PP into the substrate-binding groove of Tge2PP. Tgi2PP contains a similar topology to the periplasmic E. coli colicin M immunity protein [1].

1: Identification, structure, and function of a novel type VI secretion peptidoglycan glycoside hydrolase effector-immunity pair. Whitney JC, Chou S, Russell AB, Biboy J, Gardiner TE, Ferrin MA, Brittnacher M, Vollmer W, Mougous JD; J Biol Chem. 2013;288:26616-26624. PMID:23878199