Sandbox Reserved 199: Difference between revisions

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===Data and Results===

A 3D NMR structure was obtained with a backbone RMSD of 1.07Å. The obtained model shows a similar tertiary structure to the kidney bean shaped RNase A and is stabilized by four <scene name='Sandbox_Reserved_199/2k11_disulfide_bonds/1'>disulfide bonds</scene>. The structure shows three α-helices and seven β-~~strands~~. While this structure matches up fairly well with previous X-Ray crystallography structures of RNase 1, important differences in residue positioning can be seen in the 3D NMR structure which are not apparent in X-Ray crystallography. Specifically, certain residues with more flexibility undergo a conformational change when bound to certain substrates, such as the human ribonuclease inhibitor (HcrI) (residues R4, K6, ~~R32~~, ~~R39~~, and ~~K102)~~.

A 3D NMR structure was obtained with a backbone RMSD of 1.07Å. The obtained model shows a similar tertiary structure to the kidney bean shaped RNase A and is stabilized by four <scene name='Sandbox_Reserved_199/2k11_disulfide_bonds/1'>disulfide bonds</scene>. The structure shows three <scene name='Sandbox_Reserved_199/2k11_alpha_helix/2'>α-helices</scene> and seven <scene name='Sandbox_Reserved_199/2k11_beta_sheets/1'>β-sheets</scene>. While this structure matches up fairly well with previous X-Ray crystallography structures of RNase 1, important differences in residue positioning can be seen in the <scene name='Sandbox_Reserved_199/2k11_all_models/3'>3D NMR structure</scene> which are not apparent in X-Ray crystallography. Specifically, certain residues with more flexibility undergo a significant conformational change when bound to certain substrates, such as the human ribonuclease inhibitor (HcrI). These residues include: <scene name='Sandbox_Reserved_199/2k11_flexible_residues/1'>Arg 4, Lys 6, Arg 32, Arg 39, and Lys 102</scene>.

This data suggests an “induced-fit” model of substrate binding and may prove vital to fully understanding RNase 1’s binding specificity for Hcrl; although two residues, P42 and V43, show much more rigidity and possibly contribute some “lock-and-key” binding interaction.

Sandbox Reserved 199: Difference between revisions

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@@ Line 91: / Line 91: @@
 ===Data and Results===
-A 3D NMR structure was obtained with a backbone RMSD of 1.07Å. The obtained model shows a similar tertiary structure to the kidney bean shaped RNase A and is stabilized by four <scene name='Sandbox_Reserved_199/2k11_disulfide_bonds/1'>disulfide bonds</scene>. The structure shows three α-helices and seven β-strands.  While this structure matches up fairly well with previous X-Ray crystallography structures of RNase 1, important differences in residue positioning can be seen in the 3D NMR structure which are not apparent in X-Ray crystallography. Specifically, certain residues with more flexibility undergo a conformational change when bound to certain substrates, such as the human ribonuclease inhibitor (HcrI) (residues R4, K6, R32, R39, and K102).
+A 3D NMR structure was obtained with a backbone RMSD of 1.07Å. The obtained model shows a similar tertiary structure to the kidney bean shaped RNase A and is stabilized by four <scene name='Sandbox_Reserved_199/2k11_disulfide_bonds/1'>disulfide bonds</scene>. The structure shows three <scene name='Sandbox_Reserved_199/2k11_alpha_helix/2'>α-helices</scene> and seven <scene name='Sandbox_Reserved_199/2k11_beta_sheets/1'>β-sheets</scene>.  While this structure matches up fairly well with previous X-Ray crystallography structures of RNase 1, important differences in residue positioning can be seen in the <scene name='Sandbox_Reserved_199/2k11_all_models/3'>3D NMR structure</scene> which are not apparent in X-Ray crystallography. Specifically, certain residues with more flexibility undergo a significant conformational change when bound to certain substrates, such as the human ribonuclease inhibitor (HcrI).  These residues include: <scene name='Sandbox_Reserved_199/2k11_flexible_residues/1'>Arg 4, Lys 6, Arg 32, Arg 39, and Lys 102</scene>.
 	This data suggests an “induced-fit” model of substrate binding and may prove vital to fully understanding RNase 1’s binding specificity for Hcrl; although two residues, P42 and V43, show much more rigidity and possibly contribute some “lock-and-key” binding interaction.