Serine protease PepA (Mtb32A)

Serine protease PepA, commonly referred to as Mtb32A, is a 32 kDa secreted enzyme from Mycobacterium tuberculosis that serves as a major antigenic target for vaccine development. Encoded by the Rv0125 gene, it belongs to the peptidase S1C family and features a trypsin-like catalytic triad (His, Asp, Ser) essential for its proteolytic activity. Mtb32A is highly conserved across both virulent and avirulent strains of the M. tuberculosis complex, including the BCG strain, making it a reliable candidate for broad-spectrum immunization strategies. Biologically, it is involved in the hydrolysis of peptides and is predicted to be necessary for the bacterium's survival and virulence within the host environment. The protein is a key component of the M72/AS01E subunit vaccine, where it is fused with the Mtb39A antigen to induce potent Th1-type cell-mediated immune responses. Clinical studies have shown that vaccines containing Mtb32A can significantly reduce the risk of latent tuberculosis progressing to active disease by promoting the secretion of interferon-gamma and activating CD8+ T cells.

Other names

Rv0125PepAmtb32a32 kDa antigenSerine proteinase PepA

Stimulation of Th1 cell-mediated immune responses and activation of antigen-specific CD4+ and CD8+ T cells to provide protective immunity against Mycobacterium tuberculosis.