Structural Comparison of SHV-1 (PDB ID: 3N4I) and PDC-3 (PDB ID: 4HEF) β-Lactamases.
Catalytic serine S70 (SHV-1) and S64 (PDC3) are highlighted using stick representation. Important loops surrounding the active site are highlighted in red. In SHV-1, highlighted loops are the α3-α4 loop (residues 101-111), the Ω-loop (residues 164-179), and the hinge region (residues 213-218). In PDC-3, highlighted loops are the Ω-loop (residues 183-226) and the R2-loop (residues 280-310).