Endothelin converting enzyme 1, also known as ECE1, is a enzyme which in humans is encoded by the ECE1 gene.Endothelin-converting enzyme-1 is involved in the proteolytic processing of endothelin-1 (EDN1), -2 (EDN2), and -3 (EDN3) to biologically active peptides.

Schmidt et al. (1994) purified a membrane-bound protease activity from bovine endothelial cells that specifically converts the inactive form to EDN1. The enzyme was cleaved with trypsin and peptide sequencing analysis confirmed it to be a zinc-chelating metalloprotease containing the typical HEXXH (HELTH) motif. RT-PCR and cDNA screens were used to isolate the complete cDNAs of the bovine and human enzymes.