Why is there a difference in the amino acid region of Human ACE2 (18-652) Recombinant Protein (mFc-Tag) #83986 and Human ACE2 (18-615) Recombinant Protein (8xHis-Tag) #73775?

The slight difference in the amino acid span of these products is not significant for binding to SARS-CoV-2. The Human ACE2 (18-652) Recombinant Protein (mFc-Tag) #83986 covers the entire region up to where the protein is cleaved by Adam17 protease. The Human ACE2 (18-615) Recombinant Protein (8xHis-Tag) #73775 is slightly shorter but still contains most of the extracellular domain region. This does not significantly affect CoV-2 binding, but rather reflects the evolving design of the expressed protein. 

Last updated: October 6, 2025