Fig. 3: Electrostatic potential for substrate binding grooves.
From: Structure of the reduced microsporidian proteasome bound by PI31-like peptides in dormant spores
Surface representation of subunits important for substrate specificity in the proteolytic active sites of V. necatrix (a) or S. cerevisiae (b) (PDB-5CZ432 [https://www.rcsb.org/structure/5CZ4]), colored based Coulombic electrostatic potential in kcal/(mol·e). Active site residues are colored in yellow. Subunits harboring active sites are denoted with a •. The S3/S4 specificity regions are circled for emphasis.
