Cleaves peptide substrates after methionine, leucine, and norleucine. Physiological substrates include EZR, alpha-tubulins and the apoptosis inhibitor BIRC5/Survivin. Promotes caspase activation and subsequent apoptosis of target cells (By similarity). Granules of large granular lymphocytes. Belongs to the peptidase S1 family. Granzyme subfamily.