Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1goe
From Proteopedia
(New page: 200px<br /><applet load="1goe" size="450" color="white" frame="true" align="right" spinBox="true" caption="1goe" /> '''MONITORING THE STRUCTURAL CONSEQUENCES OF PH...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1goe.gif|left|200px]]<br /><applet load="1goe" size=" | + | [[Image:1goe.gif|left|200px]]<br /><applet load="1goe" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1goe" /> | caption="1goe" /> | ||
'''MONITORING THE STRUCTURAL CONSEQUENCES OF PHE12-->D-PHE12 AND LEU15-->AIB15 SUBSTITUTION IN H/R CORTICOTROPIN RELEASING HORMONE: IMPLICATIONS FOR DESIGN OF CRH ANTAGONISTS.'''<br /> | '''MONITORING THE STRUCTURAL CONSEQUENCES OF PHE12-->D-PHE12 AND LEU15-->AIB15 SUBSTITUTION IN H/R CORTICOTROPIN RELEASING HORMONE: IMPLICATIONS FOR DESIGN OF CRH ANTAGONISTS.'''<br /> | ||
==Overview== | ==Overview== | ||
| - | A new human/rat CRH analogue has been synthesized using the Fmoc/tBu | + | A new human/rat CRH analogue has been synthesized using the Fmoc/tBu solid-phase synthetic protocol. The sequence of the new peptide differs from the original in two positions, 12 and 15, at which the native amino acids l-phenylalanine 12 and l-leucine 15 have been replaced by the nonprotein amino acids d-phenylalanine and alpha-aminoisobutyric acid (Aib), respectively. The high resolution three-dimensional solution structure of [d-Phe12, Aib15]CRH has been determined by 688 distance constraints (656 meaningful NOE and 32 H-bonds distance limits) and 21 angle constraints. A family of 40 energy-minimized conformers was obtained with average rmsd of 0.39 +/- 0.16 A and 0.99 +/- 0.13 A for backbone and heavy atoms, respectively, and distance penalty functions of 0.42 +/- 0.03 A2. The NMR data acquired in a solvent system of water/trifluoroethanol (34%/66%, v/v) revealed that this 41-polypeptide adopts an almost linear helical structure in solution with helical content which reaches an 84% of the residues. Structural analysis confirmed the existence of two helical peptide fragments. The first was comprised of residues Ile6-Arg16 and the second of residues Glu20-Ile40, forming an angle of 34.2 degrees. The structural differences with respect to the native peptide have been identified in the region d-Phe12-Glu20 where double substitution at positions 12 and 15 seems to perturb the elements of the native 35-residue helix. These structural rearrangements promote non-native intramolecular interactions in the region of the molecule between either the hydrophobic side-chains of d-Phe12, Aib15 and Leu18, or the charged groups of the residue pairs Arg16-Glu20 and His13-Glu17 being responsible for changes in hormonal functionality. This CRH analogue currently exhibits lack of any activity. |
==About this Structure== | ==About this Structure== | ||
| - | 1GOE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ] with NH2 as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1GOE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ] with <scene name='pdbligand=NH2:'>NH2</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GOE OCA]. |
==Reference== | ==Reference== | ||
| Line 15: | Line 15: | ||
[[Category: Pairas, G.]] | [[Category: Pairas, G.]] | ||
[[Category: Papazacharias, S.]] | [[Category: Papazacharias, S.]] | ||
| - | [[Category: Spyroulias, G | + | [[Category: Spyroulias, G A.]] |
[[Category: NH2]] | [[Category: NH2]] | ||
[[Category: corticotropin releasing hormone]] | [[Category: corticotropin releasing hormone]] | ||
| Line 23: | Line 23: | ||
[[Category: synthetic analogues]] | [[Category: synthetic analogues]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:52:15 2008'' |
Revision as of 10:52, 21 February 2008
|
MONITORING THE STRUCTURAL CONSEQUENCES OF PHE12-->D-PHE12 AND LEU15-->AIB15 SUBSTITUTION IN H/R CORTICOTROPIN RELEASING HORMONE: IMPLICATIONS FOR DESIGN OF CRH ANTAGONISTS.
Overview
A new human/rat CRH analogue has been synthesized using the Fmoc/tBu solid-phase synthetic protocol. The sequence of the new peptide differs from the original in two positions, 12 and 15, at which the native amino acids l-phenylalanine 12 and l-leucine 15 have been replaced by the nonprotein amino acids d-phenylalanine and alpha-aminoisobutyric acid (Aib), respectively. The high resolution three-dimensional solution structure of [d-Phe12, Aib15]CRH has been determined by 688 distance constraints (656 meaningful NOE and 32 H-bonds distance limits) and 21 angle constraints. A family of 40 energy-minimized conformers was obtained with average rmsd of 0.39 +/- 0.16 A and 0.99 +/- 0.13 A for backbone and heavy atoms, respectively, and distance penalty functions of 0.42 +/- 0.03 A2. The NMR data acquired in a solvent system of water/trifluoroethanol (34%/66%, v/v) revealed that this 41-polypeptide adopts an almost linear helical structure in solution with helical content which reaches an 84% of the residues. Structural analysis confirmed the existence of two helical peptide fragments. The first was comprised of residues Ile6-Arg16 and the second of residues Glu20-Ile40, forming an angle of 34.2 degrees. The structural differences with respect to the native peptide have been identified in the region d-Phe12-Glu20 where double substitution at positions 12 and 15 seems to perturb the elements of the native 35-residue helix. These structural rearrangements promote non-native intramolecular interactions in the region of the molecule between either the hydrophobic side-chains of d-Phe12, Aib15 and Leu18, or the charged groups of the residue pairs Arg16-Glu20 and His13-Glu17 being responsible for changes in hormonal functionality. This CRH analogue currently exhibits lack of any activity.
About this Structure
1GOE is a Single protein structure of sequence from [1] with as ligand. Full crystallographic information is available from OCA.
Reference
Monitoring the structural consequences of Phe12-->D-Phe and Leu15-->Aib substitution in human/rat corticotropin releasing hormone. Implications for design of CRH antagonists., Spyroulias GA, Papazacharias S, Pairas G, Cordopatis P, Eur J Biochem. 2002 Dec;269(24):6009-19. PMID:12473096
Page seeded by OCA on Thu Feb 21 12:52:15 2008
