The catalytic/protease-like domains of the c-SPs and c-SPHs were compared, including 50 residues upstream of the conserved histidine and 50 residues downstream of the active site serine. Bootstrap values of greater than 100 or 200 (1000 trials) are indicated at the corresponding nodes. Vertical bars and numbers (1a, 1b, and 2) indicate groups of serine protease.