1mcw
From Proteopedia
(New page: 200px<br /><applet load="1mcw" size="450" color="white" frame="true" align="right" spinBox="true" caption="1mcw, resolution 3.5Å" /> '''THREE-DIMENSIONAL STR...) |
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| - | [[Image:1mcw.jpg|left|200px]]<br /><applet load="1mcw" size=" | + | [[Image:1mcw.jpg|left|200px]]<br /><applet load="1mcw" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1mcw, resolution 3.5Å" /> | caption="1mcw, resolution 3.5Å" /> | ||
'''THREE-DIMENSIONAL STRUCTURE OF A HYBRID LIGHT CHAIN DIMER. PROTEIN ENGINEERING OF A BINDING CAVITY'''<br /> | '''THREE-DIMENSIONAL STRUCTURE OF A HYBRID LIGHT CHAIN DIMER. PROTEIN ENGINEERING OF A BINDING CAVITY'''<br /> | ||
==Overview== | ==Overview== | ||
| - | An attempt was made to engineer a binding site and check its structure by | + | An attempt was made to engineer a binding site and check its structure by X-ray analysis. Two human light chains (Mcg and Weir), with "variable" domain sequences differing in 36 positions, were hybridized into a heterologous dimer and crystallized in ammonium sulfate by the same procedure used for the trigonal form of the Mcg dimer. The three-dimensional structure of the hybrid was determined at 3.5-A resolution by difference Fourier analysis, interactive model building with computer graphics and crystallographic refinement. In the heterologous dimer, the Weir protein behaved as the structural analog of the heavy chain in an antigen binding fragment, while the Mcg protein assumed the role of the light chain component. The hybrid and the Mcg dimer were closely similar in overall structure, an observation probably correlated with the deliberate cleavage of the intrachain disulfide bond in the variable domain of the Weir protein during the hybridization procedure. Examination of the crystal structure of the hybrid suggested that the cleavage resulted in the relaxation of restraints which might otherwise have interfered with the formation of an Mcg-like dimer. There were six substitutions among the residues lining the binding cavities of the hybrid and Mcg dimer. These substitutions significantly affected the sizes, shapes and binding properties of the two cavities. |
==About this Structure== | ==About this Structure== | ||
| - | 1MCW is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http:// | + | 1MCW is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MCW OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Edmundson, A | + | [[Category: Edmundson, A B.]] |
| - | [[Category: Ely, K | + | [[Category: Ely, K R.]] |
| - | [[Category: Herron, J | + | [[Category: Herron, J N.]] |
[[Category: immunoglobulin]] | [[Category: immunoglobulin]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:53:59 2008'' |
Revision as of 11:54, 21 February 2008
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THREE-DIMENSIONAL STRUCTURE OF A HYBRID LIGHT CHAIN DIMER. PROTEIN ENGINEERING OF A BINDING CAVITY
Overview
An attempt was made to engineer a binding site and check its structure by X-ray analysis. Two human light chains (Mcg and Weir), with "variable" domain sequences differing in 36 positions, were hybridized into a heterologous dimer and crystallized in ammonium sulfate by the same procedure used for the trigonal form of the Mcg dimer. The three-dimensional structure of the hybrid was determined at 3.5-A resolution by difference Fourier analysis, interactive model building with computer graphics and crystallographic refinement. In the heterologous dimer, the Weir protein behaved as the structural analog of the heavy chain in an antigen binding fragment, while the Mcg protein assumed the role of the light chain component. The hybrid and the Mcg dimer were closely similar in overall structure, an observation probably correlated with the deliberate cleavage of the intrachain disulfide bond in the variable domain of the Weir protein during the hybridization procedure. Examination of the crystal structure of the hybrid suggested that the cleavage resulted in the relaxation of restraints which might otherwise have interfered with the formation of an Mcg-like dimer. There were six substitutions among the residues lining the binding cavities of the hybrid and Mcg dimer. These substitutions significantly affected the sizes, shapes and binding properties of the two cavities.
About this Structure
1MCW is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of a hybrid light chain dimer: protein engineering of a binding cavity., Ely KR, Herron JN, Edmundson AB, Mol Immunol. 1990 Feb;27(2):101-14. PMID:2108322
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