Catalyzes the cleavage of sphingomyelin, a major lipid in eukaryotic cells, into ceramide and phosphocholine, which are then utilized by M.tuberculosis as carbon, nitrogen and phosphorus sources, respectively. Thus, enables M.tuberculosis to utilize sphingomyelin as a source of several essential nutrients for intracellular growth during infection. Furthermore, lyses erythrocytes and constitutes the main hemolytic factor of M.tuberculosis. a sphingomyelin + H2O = an N-acylsphing-4-enine + H(+) + phosphocholine kcat is 1797 sec(-1). Is most active at neutral pH. Rv0888 protein levels are increased by 5-fold after contact with erythrocytes for 24 hours, and by 100-fold in the presence of sphingomyelin as the sole carbon source. Consists of a surface-exposed C-terminal sphingomyelinase domain and a putative outer membrane-spanning N-terminal channel domain able to mediate glucose and phosphocholine uptake across the outer membrane. Cells lacking this gene do not grow on sphingomyelin as a sole carbon source anymore and replicate poorly in macrophages indicating that M.tuberculosis utilizes sphingomyelin during infection. Moreover, deletion of this gene reduces lysis of erythrocytes by twofold compared with wild-type. Belongs to the SpmT family.