1txe: Difference between revisions

Revision as of 16:18, 21 February 2008

Solution structure of the active-centre mutant Ile14Ala of the histidine-containing phosphocarrier protein (HPr) from Staphylococcus carnosus

OverviewOverview

High-pressure NMR experiments performed on the histidine-containing phosphocarrier protein (HPr) from Staphylococcus carnosus have shown that residue Ile14, which is located in the active-centre loop, exhibits a peculiarly small pressure response. In contrast, the rest of the loop shows strong pressure effects as is expected for typical protein interaction sites. To elucidate the structural role of this residue, the mutant protein HPr(I14A), in which Ile14 is replaced by Ala, was produced and studied by solution NMR spectroscopy. On the basis of 1406 structural restraints including 20 directly detected hydrogen bonds, 49 1H(N)-15N, and 25 1H(N)-1Halpha residual dipolar couplings, a well resolved three-dimensional structure could be determined. The overall fold of the protein is not influenced by the mutation but characteristic conformational changes are introduced into the active-centre loop. They lead to a displacement of the ring system of His15 and a distortion of the N-terminus of the first helix, which supports the histidine ring. In addition, the C-terminal helix is bent because the side chain of Leu86 located at the end of this helix partly fills the hydrophobic cavity created by the mutation. Xenon, which is known to occupy hydrophobic cavities, causes a partial reversal of the mutation-induced structural effects. The observed structural changes explain the reduced phosphocarrier activity of the mutant and agree well with the earlier suggestion that Ile14 represents an anchoring point stabilizing the active-centre loop in its correct conformation.

About this StructureAbout this Structure

1TXE is a Single protein structure of sequence from Staphylococcus carnosus. Full crystallographic information is available from OCA.

ReferenceReference

Solution structure of the active-centre mutant I14A of the histidine-containing phosphocarrier protein from Staphylococcus carnosus., Moglich A, Koch B, Gronwald W, Hengstenberg W, Brunner E, Kalbitzer HR, Eur J Biochem. 2004 Dec;271(23-24):4815-24. PMID:15606769

Page seeded by OCA on Thu Feb 21 15:18:20 2008

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OCA

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 '''Solution structure of the active-centre mutant Ile14Ala of the histidine-containing phosphocarrier protein (HPr) from Staphylococcus carnosus'''<br />
 ==Overview==
-High-pressure NMR experiments performed on the histidine-containing, phosphocarrier protein (HPr) from Staphylococcus carnosus have shown that, residue Ile14, which is located in the active-centre loop, exhibits a, peculiarly small pressure response. In contrast, the rest of the loop, shows strong pressure effects as is expected for typical protein, interaction sites. To elucidate the structural role of this residue, the, mutant protein HPr(I14A), in which Ile14 is replaced by Ala, was produced, and studied by solution NMR spectroscopy. On the basis of 1406 structural, restraints including 20 directly detected hydrogen bonds, 49 1H(N)-15N, and 25 1H(N)-1Halpha residual dipolar couplings, a well resolved, three-dimensional structure could be determined. The overall fold of the, protein is not influenced by the mutation but characteristic, conformational changes are introduced into the active-centre loop. They, lead to a displacement of the ring system of His15 and a distortion of the, N-terminus of the first helix, which supports the histidine ring. In, addition, the C-terminal helix is bent because the side chain of Leu86, located at the end of this helix partly fills the hydrophobic cavity, created by the mutation. Xenon, which is known to occupy hydrophobic, cavities, causes a partial reversal of the mutation-induced structural, effects. The observed structural changes explain the reduced, phosphocarrier activity of the mutant and agree well with the earlier, suggestion that Ile14 represents an anchoring point stabilizing the, active-centre loop in its correct conformation.
+High-pressure NMR experiments performed on the histidine-containing phosphocarrier protein (HPr) from Staphylococcus carnosus have shown that residue Ile14, which is located in the active-centre loop, exhibits a peculiarly small pressure response. In contrast, the rest of the loop shows strong pressure effects as is expected for typical protein interaction sites. To elucidate the structural role of this residue, the mutant protein HPr(I14A), in which Ile14 is replaced by Ala, was produced and studied by solution NMR spectroscopy. On the basis of 1406 structural restraints including 20 directly detected hydrogen bonds, 49 1H(N)-15N, and 25 1H(N)-1Halpha residual dipolar couplings, a well resolved three-dimensional structure could be determined. The overall fold of the protein is not influenced by the mutation but characteristic conformational changes are introduced into the active-centre loop. They lead to a displacement of the ring system of His15 and a distortion of the N-terminus of the first helix, which supports the histidine ring. In addition, the C-terminal helix is bent because the side chain of Leu86 located at the end of this helix partly fills the hydrophobic cavity created by the mutation. Xenon, which is known to occupy hydrophobic cavities, causes a partial reversal of the mutation-induced structural effects. The observed structural changes explain the reduced phosphocarrier activity of the mutant and agree well with the earlier suggestion that Ile14 represents an anchoring point stabilizing the active-centre loop in its correct conformation.
 ==About this Structure==
-TXE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_carnosus Staphylococcus carnosus]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1TXE OCA].
+TXE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_carnosus Staphylococcus carnosus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TXE OCA].
 ==Reference==
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 [[Category: Brunner, E.]]
 [[Category: Hengstenberg, W.]]
-[[Category: Kalbitzer, H.R.]]
+[[Category: Kalbitzer, H R.]]
 [[Category: Koch, B.]]
 [[Category: Moeglich, A.]]
-[[Category: SPINE, Structural.Proteomics.in.Europe.]]
+[[Category: SPINE, Structural Proteomics in Europe.]]
 [[Category: open-faced beta-sandwich]]
 [[Category: spine]]
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 [[Category: structural proteomics in europe]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 03:40:04 2007''
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