Sandbox Reserved 197: Difference between revisions

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==='''Disulfide Bonds'''===

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-cys84/4'>Cys26-Cys84</scene>, <scene name='Sandbox_Reserved_197/Cys58-cys110/4'>Cys58-Cys110</scene>, <scene name='Sandbox_Reserved_197/40-95_disulfide_native_form/4'>Cys40-Cys95</scene>, and <scene name='Sandbox_Reserved_197/Cys65-cys72/5'>Cys65-Cys72</scene>. Cys26-Cys84 and Cys58-Cys110 stabilize an interaction between an α-helix and a β-sheet. This connection is the main contributor to the thermodynamic stability of the enzyme.

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-cys84/5'>Cys26-Cys84</scene>, <scene name='Sandbox_Reserved_197/Cys58-cys110/5'>Cys58-Cys110</scene>, <scene name='Sandbox_Reserved_197/40-95_disulfide_native_form/5'>Cys40-Cys95</scene>, and <scene name='Sandbox_Reserved_197/Cys65-cys72/6'>Cys65-Cys72</scene>. Cys26-Cys84 and Cys58-Cys110 stabilize an interaction between an α-helix and a β-sheet. This connection is the main contributor to the thermodynamic stability of the enzyme.

Measurements of protein activity upon removal of disulfide bridges show that the active center is very small and not all disulfide bridges are essential for reactivity of the protein. However, removal of disulfide bonds destabilizes the hydrophobic core and decreases the rate of folding. RNase A actually has a rate-determining three-disulfide intermediate. An analog of this, <scene name='Sandbox_Reserved_197/C40-95a_variant/6'>C[40,95]A</scene>, shows RNase A, missing the disulfide bond, Cys40-Cys95, that would normally occur here. As you can see in the variant and the 2D structure, there are only 3 disulfide bonds present, shown in red.

Measurements of protein activity upon removal of disulfide bridges show that the active center is very small and not all disulfide bridges are essential for reactivity of the protein. However, removal of disulfide bonds destabilizes the hydrophobic core and decreases the rate of folding. RNase A actually has a rate-determining three-disulfide intermediate. An analog of this, <scene name='Sandbox_Reserved_197/C40-95a_variant/7'>C[40,95]A</scene>, shows RNase A, missing the disulfide bond, Cys40-Cys95, that would normally occur here. As you can see in the variant and the 2D structure, there are only 3 disulfide bonds present, shown in red.

==='''Summary'''===

Sandbox Reserved 197: Difference between revisions

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@@ Line 21: / Line 21: @@
 ==='''Disulfide Bonds'''===
-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-cys84/4'>Cys26-Cys84</scene>, <scene name='Sandbox_Reserved_197/Cys58-cys110/4'>Cys58-Cys110</scene>, <scene name='Sandbox_Reserved_197/40-95_disulfide_native_form/4'>Cys40-Cys95</scene>, and <scene name='Sandbox_Reserved_197/Cys65-cys72/5'>Cys65-Cys72</scene>.  Cys26-Cys84 and Cys58-Cys110 stabilize an interaction between an α-helix and a β-sheet.  This connection is the main contributor to the thermodynamic stability of the enzyme.
+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-cys84/5'>Cys26-Cys84</scene>, <scene name='Sandbox_Reserved_197/Cys58-cys110/5'>Cys58-Cys110</scene>, <scene name='Sandbox_Reserved_197/40-95_disulfide_native_form/5'>Cys40-Cys95</scene>, and <scene name='Sandbox_Reserved_197/Cys65-cys72/6'>Cys65-Cys72</scene>.  Cys26-Cys84 and Cys58-Cys110 stabilize an interaction between an α-helix and a β-sheet.  This connection is the main contributor to the thermodynamic stability of the enzyme.
-Measurements of protein activity upon removal of disulfide bridges show that the active center is very small and not all disulfide bridges are essential for reactivity of the protein. However, removal of disulfide bonds destabilizes the hydrophobic core and decreases the rate of folding. RNase A actually has a rate-determining three-disulfide intermediate.  An analog of this, <scene name='Sandbox_Reserved_197/C40-95a_variant/6'>C[40,95]A</scene>, shows RNase A, missing the disulfide bond, Cys40-Cys95, that would normally occur here.  As you can see in the variant and the 2D structure, there are only 3 disulfide bonds present, shown in red.
+Measurements of protein activity upon removal of disulfide bridges show that the active center is very small and not all disulfide bridges are essential for reactivity of the protein. However, removal of disulfide bonds destabilizes the hydrophobic core and decreases the rate of folding. RNase A actually has a rate-determining three-disulfide intermediate.  An analog of this, <scene name='Sandbox_Reserved_197/C40-95a_variant/7'>C[40,95]A</scene>, shows RNase A, missing the disulfide bond, Cys40-Cys95, that would normally occur here.  As you can see in the variant and the 2D structure, there are only 3 disulfide bonds present, shown in red.
 ==='''Summary'''===