1bmg
From Proteopedia
(New page: 200px<br /><applet load="1bmg" size="450" color="white" frame="true" align="right" spinBox="true" caption="1bmg, resolution 2.50Å" /> '''CRYSTAL STRUCTURE OF...) |
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| - | [[Image:1bmg.jpg|left|200px]]<br /><applet load="1bmg" size=" | + | [[Image:1bmg.jpg|left|200px]]<br /><applet load="1bmg" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1bmg, resolution 2.50Å" /> | caption="1bmg, resolution 2.50Å" /> | ||
'''CRYSTAL STRUCTURE OF BOVINE BETA2-MICROGLOBULIN'''<br /> | '''CRYSTAL STRUCTURE OF BOVINE BETA2-MICROGLOBULIN'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The three-dimensional structure of beta 2-microglobulin, the light chain | + | The three-dimensional structure of beta 2-microglobulin, the light chain of the major histocompatibility complex class I antigens, has been determined by x-ray crystallography. An electron density map of the bovine protein was calculated at a nominal resolution of 2.9 A by using the methods of multiple isomorphous replacement and electron density modification refinement. The molecule is approximately 45 X 25 X 20 A in size. Almost half of the amino acid residues participate in two large beta structures, one of four strands and the other of three, linked by a central disulfide bond. The molecule thus strongly resembles Ig constant domains in polypeptide chain folding and overall tertiary structure. Amino acid residues that are the same in the sequences of beta 2-microglobulin and Ig constant domains are predominantly in the interior of the molecule, whereas residues conserved among beta 2-microglobulins from different species are both in the interior and on the molecular surface. In the crystals studied, the molecule is clearly monomeric, consistent with the observation that beta 2-microglobulin, unlike Ig constant domains, apparently does not form dimers in vivo but associates with the heavy chains of major histocompatibility complex antigens. Our results demonstrate that, at the level of detailed three-dimensional structure, the light chain of the major histocompatibility class I antigens belongs to a superfamily of structures related to the Ig constant domains. |
==About this Structure== | ==About this Structure== | ||
| - | 1BMG is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. Full crystallographic information is available from [http:// | + | 1BMG is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BMG OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Bos taurus]] | [[Category: Bos taurus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Becker, J | + | [[Category: Becker, J W.]] |
| - | [[Category: Junior, G | + | [[Category: Junior, G N.Reeke.]] |
[[Category: lactollin]] | [[Category: lactollin]] | ||
[[Category: light chain]] | [[Category: light chain]] | ||
[[Category: mhc-i histocompatibility antigen]] | [[Category: mhc-i histocompatibility antigen]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:56:50 2008'' |
Revision as of 09:56, 21 February 2008
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CRYSTAL STRUCTURE OF BOVINE BETA2-MICROGLOBULIN
Overview
The three-dimensional structure of beta 2-microglobulin, the light chain of the major histocompatibility complex class I antigens, has been determined by x-ray crystallography. An electron density map of the bovine protein was calculated at a nominal resolution of 2.9 A by using the methods of multiple isomorphous replacement and electron density modification refinement. The molecule is approximately 45 X 25 X 20 A in size. Almost half of the amino acid residues participate in two large beta structures, one of four strands and the other of three, linked by a central disulfide bond. The molecule thus strongly resembles Ig constant domains in polypeptide chain folding and overall tertiary structure. Amino acid residues that are the same in the sequences of beta 2-microglobulin and Ig constant domains are predominantly in the interior of the molecule, whereas residues conserved among beta 2-microglobulins from different species are both in the interior and on the molecular surface. In the crystals studied, the molecule is clearly monomeric, consistent with the observation that beta 2-microglobulin, unlike Ig constant domains, apparently does not form dimers in vivo but associates with the heavy chains of major histocompatibility complex antigens. Our results demonstrate that, at the level of detailed three-dimensional structure, the light chain of the major histocompatibility class I antigens belongs to a superfamily of structures related to the Ig constant domains.
About this Structure
1BMG is a Single protein structure of sequence from Bos taurus. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of beta 2-microglobulin., Becker JW, Reeke GN Jr, Proc Natl Acad Sci U S A. 1985 Jun;82(12):4225-9. PMID:3889925
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