Actinidin

Actinidin (actinidain, Actinidia anionic protease, proteinase A2 of Kiwi fruit Actinidia chinensis) is a cysteine protease.
--https://en.wikipedia.org/wiki/Actinidain

The STL file contains a representation of the protein in cartoon form with catalytic residues represented as spheres. Cysteine disulfide bonds are also represented as spheres. Model based on the Protein Data Bank entry 2ACT:
--http://www.pdb.org/pdb/explore/explore.do?pdbId=2act

Model created using VMD:
http://www.ks.uiuc.edu/Research/vmd/