Inhibits nitric oxide (NO) production in activated macrophages (PubMed:23448669, PubMed:28071726). Acts by inhibiting expression of the host inducible nitric oxide synthase (iNOS) (PubMed:28071726). PPE2 is translocated into the host macrophage nucleus, where it interacts with a GATA-binding site overlapping with the TATA box of NOS2 (iNOS) promoter, and strongly inhibits NOS2 gene transcription (PubMed:28071726). Reduction in NO production in turn facilitates intracellular survival of the bacilli inside the macrophage (PubMed:28071726). In addition, disrupts the assembly of NADPH oxidase complex, which inhibits NADPH oxidase-mediated reactive oxygen species (ROS) generation in macrophages and favors M.tuberculosis survival (PubMed:31375544). Acts by interacting with NCF2, the cytosolic subunit of NADPH oxidase, and preventing translocation of NCF2 and NCF1 to the membrane, which causes a reduction of the functional assembly of NADPH oxidase complex and a decrease in NADPH oxidase activity (PubMed:31375544). Translocated into the macrophage nucleus via the classical importin alpha/beta pathway. Contains a conserved PPE N-terminal domain and a variable C-terminal domain (PubMed:31375544). The C-terminal region includes a SH3-like region, a leucine zipper DNA-binding motif and a functional nuclear localization signal (NLS) (PubMed:28071726, PubMed:31375544). Shows a strong immunoreactivity toward tuberculosis patient sera compared to that of BCG-vaccinated controls. Could be an attractive candidate for serodiagnosis to discriminate patients with active tuberculosis from BCG-vaccinated individuals (PubMed:23827809, PubMed:26364913). Could diagnose both pulmonary and extrapulmonary tuberculosis cases (PubMed:23827809). However, it has lower sensitivity to detect smear negative and extrapulmonary cases as compared to PPE17/Rv1168c (PubMed:26364913). Was identified as a high-confidence drug target. Belongs to the mycobacterial PPE family.