LGMN, also known as legumain, is a cysteine endopeptidase that shows strict specificity for hydrolysis of asparaginyl bonds. It can also cleave aspartyl bonds slowly, especially under acidic conditions. It required for normal lysosomal protein degradation in renal proximal tubules. They are required for normal degradation of internalized EGFR and play a role in the regulation of cell proliferation via its role in EGFR degradation. Recombinant human LGMN, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.