Human CD73, also known as 5'- nucleotidase and Ecto-5'-nucleotidase, GenBank Accession No. NM_002526, a.a. 27-547 with C-terminal His-tag, expressed in a HEK293 cell expression system. MW = 58.6 kDa. This protein runs at a higher MW by SDS-PAGE due to glycosylation.