Fig. 9
From: Ultra-high resolution X-ray structure of orthorhombic bovine pancreatic Ribonuclease A at 100K
a The β- sheet regions in Orthorhombic RNase A. This shows that in the central region of the assembly the 3 β-sheets are approximately parallel. The red numbers indicate the number of waters at that site. There are several stretches with no water: notably 42–43 and, 46–48 in β-sheet I; 99, 100, 101, 102 in β-Sheet II. Drawn with Biovia [19]. b Shows how β-Sheet I is strongly linked to the active site through one of its residues His-12, (“The active site details”). The active site sulphate is SO41152 in the.pdb file and the EtOH is EOH A 203. c Shows how this association is strengthened further by Hydrogen bonding to β-Sheet II and β-Sheet III. The β-sheet structure and α-helix I thus make significant contributions to the stability of the active site. the EtOH is EOH A 203