Fig. 3
From: Ultra-high resolution X-ray structure of orthorhombic bovine pancreatic Ribonuclease A at 100K
The sequence Ala-64–Cys-65–Lys-66: a Orthorhombic Ribonuclease A showing the extended major conformation of Lys66. b Monoclinic RNase A 3RN3 showing the single coiled side-chain conformation of Lys-66. Water oxygens are shown as red spheres; Hydrogen bonds are shown as broken lines; there is an ethanol EOH A 205 molecule linked in the orthorhombic form to Lys-66 side-chain via a water molecule; this ethanol is also linked to Asn-62 and Ser-123. Drawn with Biovia [19]. Note: it is thought that Lys-66 may have a role in the enzyme mechanism