Similarly, SMAD-specific E3 ubiquitin-ligase protein 1 (Smurf1) has been demonstrated to mediate K48- but not K63-ubiquitination and the recruitment of the autophagy adaptor NBR1 during M. tuberculosis infection to control its replication in human macrophages and to associate with bacteria present in the lung of patients with pulmonary TB (33). This evidence concerns the gene SMURF1 and pulmonary tuberculosis.