MEP1B, also known as meprin A subunit beta, is a member of the astacin family of zinc endopeptidases 1, 2. It is disulfide-linked, tetrameric metalloendopeptidases in renal brush border membranes. It is highly regulated, secreted, and cell-surface metalloendopeptidases that are abundantly expressed in the kidney and intestine. Recombinant mouse MEP1B, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.