Sandbox Reserved 197: Difference between revisions

Another important feature of the folding of RNase A is the presence of four disulfide bonds.  These bonds contribute to the thermal stability and the rate of folding of RNase A.  The residues involved in these linkages include <scene name='Sandbox_Reserved_197/Cys26-cys84/1'>Cys26-Cys84</scene>, <scene name='Sandbox_Reserved_197/Cys58-cys110/1'>Cys58-Cys110</scene>, <scene name='Sandbox_Reserved_197/40-95_disulfide_native_form/3'>Cys40-Cys95</scene>, and <scene name='Sandbox_Reserved_197/Cys65-cys72/1'>Cys65-Cys72</scene>.  Cys26-Cys84 and Cys58-Cys110 create an interaction between an alpha-helix and a beta sheet.  This connection is the main contributor to the thermodynamic stability.  RNase A actually has a rate-determining three-disulfide intermediate.  An analog of this, <scene name='Sandbox_Reserved_197/C40-95a_variant/2'>[C40,95]A</scene>, shows RNase A, missing the disulfide bond that would normally occur here, <scene name='Sandbox_Reserved_197/40-95_disulfide_native_form/3'>Cys40-Cys95</scene>.  As you can see in the variant, there are only 3 disulfide bonds present, shown in blue.