Purification of ADAM 10 from bovine spleen as a TNFα convertase

We have purified a protease with characteristics of TNFα convertase from bovine spleen membranes. Peptide sequencing of the purified protein identified it as ADAM 10 (Genbank accession no. Z21961). This metalloprotease cleaves a recombinant proTNFα substrate to mature TNFα, and can cleave a synthetic peptide substrate to yield the mature TNFα amino terminus in vitro. The enzyme is sensitive to a hydroxamate inhibitor of MMPs, but insensitive to phosphoramidon. In addition, cloned ADAM 10 mediates proTNFα processing in a processing-incompetent cell line.