Cloning, expression, purification, and characterization of a glutamate-specific endopeptidase from Bacillus licheniformis

► Immobilized metal affinity chromatography was innovatively used to purify GSE-BL. ► Gradual maturation process of GSE-BL was revealed. ► The presence of pro-peptide could decrease specific activity of GSE-BL. ► GSE-BL is a relatively stable and specific endopeptidase.