Fig. 3: The stem domain of TMPRSS2 is structurally similar to TMPRSS13.
From: Structure and activity of human TMPRSS2 protease implicated in SARS-CoV-2 activation
a, Superposed serine protease domains (blue), and SRCR (green) of TMPRSS13, TMPRSS2 and hepsin. The LDLR domain of TMPRSS13 is shown in magenta with bound calcium in orange and the absence of the LDLR in TMPRSS2 is highlighted in red. b, Ribbon representation of the superimposed SRCR domains of TMPRSS2 (blue), Hepsin (magenta, PDB 1Z8G) and TMPRSS13 (orange, PDB 6KD5). c, Superposed models of TMPRSS13 in cyan and TMPRSS2 in salmon and its symmetry-related molecule in yellow. The LDLR domain that is present in TMPRSS13 structure would clash with the symmetry-related molecule in the TMPRSS2 crystal lattice, suggesting that the LDLR domain is not present in the crystal lattice.
