Subtilisin E is a calcium-dependent serine endopeptidase with broad substrate specificity. The enzyme cleaves peptide bonds preferentially on the carboxyl side of hydrophobic amino acid residueas. The enzyme exhibits maximum activity at pH 7.5-8.0 and 50-55°C. The presence of calcium ions (1-5 mM CaCl2) in the reaction buffer is recommended to maintain structural stability and catalytic efficiency. Subtilisin E is recommended for controlled protein hydrolysis, peptide mapping and biochemical research.