Discovery and cryoEM structure of FPM13, a periplasmic metalloprotein unique to Francisella

We report the identification and cryoEM structure of the Francisella protein FTN_1118, a previously uncharacterized 13 kDa periplasmic protein unique to the Francisella genus. The protein was serendipitously discovered during purification of Francisella type VI secretion system (T6SS) effector proteins and is hereby designated as FPM13 (Francisella Periplasmic Metalloprotein, 13 kDa) based on its cellular and biochemical properties. Identified by the cryoID approach based on our cryoEM density m