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9lyz
From Proteopedia
(New page: 200px<br /><applet load="9lyz" size="350" color="white" frame="true" align="right" spinBox="true" caption="9lyz, resolution 2.5Å" /> '''X-RAY CRYSTALLOGRAPHY...) |
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==Overview== | ==Overview== | ||
| - | Hen egg white lysozyme was the first enzyme whose structure was determined | + | Hen egg white lysozyme was the first enzyme whose structure was determined by X-ray crystallography. The proposed mechanism based on this structure involves the distortion of the saccharide residue (2-acetamido-2-deoxy-D-muramic acid, NAM) in the natural substrate (an alternating beta (1 leads to 4) linked oligomer of 2-acetamido-2-deoxy-D-glucose (NAG) and NAM residues) bound to site D in the binding cleft. The importance of substrate distortion has prompted numerous enzymatic, chemical, theoretical, and physical studies, but there is little direct crystallographic evidence on the conformation of a NAM residue bound at site D. We now present the X-ray structure of the non-hydrolysed trisaccharide NAM-NAG-NAM bound in subsites B, C, D. Our interpretation of the 2.5-A resolution difference map does not involve distortion of this residue in site D. Comparison with the structure of the delta-lactone derived from tetra N-acetylchitotetraose (NAG)3NAL) bound to lysozyme suggests we may be looking at a Michaelis complex. |
==About this Structure== | ==About this Structure== | ||
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X-ray crystallography of the binding of the bacterial cell wall trisaccharide NAM-NAG-NAM to lysozyme., Kelly JA, Sielecki AR, Sykes BD, James MN, Phillips DC, Nature. 1979 Dec 20-27;282(5741):875-8. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=514367 514367] | X-ray crystallography of the binding of the bacterial cell wall trisaccharide NAM-NAG-NAM to lysozyme., Kelly JA, Sielecki AR, Sykes BD, James MN, Phillips DC, Nature. 1979 Dec 20-27;282(5741):875-8. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=514367 514367] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: James, M | + | [[Category: James, M N.G.]] |
| - | [[Category: Kelly, J | + | [[Category: Kelly, J A.]] |
[[Category: hydrolase (o-glycosyl)]] | [[Category: hydrolase (o-glycosyl)]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:18:52 2008'' |
Revision as of 17:18, 21 February 2008
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X-RAY CRYSTALLOGRAPHY OF THE BINDING OF THE BACTERIAL CELL WALL TRISACCHARIDE NAM-NAG-NAM TO LYSOZYME
Overview
Hen egg white lysozyme was the first enzyme whose structure was determined by X-ray crystallography. The proposed mechanism based on this structure involves the distortion of the saccharide residue (2-acetamido-2-deoxy-D-muramic acid, NAM) in the natural substrate (an alternating beta (1 leads to 4) linked oligomer of 2-acetamido-2-deoxy-D-glucose (NAG) and NAM residues) bound to site D in the binding cleft. The importance of substrate distortion has prompted numerous enzymatic, chemical, theoretical, and physical studies, but there is little direct crystallographic evidence on the conformation of a NAM residue bound at site D. We now present the X-ray structure of the non-hydrolysed trisaccharide NAM-NAG-NAM bound in subsites B, C, D. Our interpretation of the 2.5-A resolution difference map does not involve distortion of this residue in site D. Comparison with the structure of the delta-lactone derived from tetra N-acetylchitotetraose (NAG)3NAL) bound to lysozyme suggests we may be looking at a Michaelis complex.
About this Structure
9LYZ is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
X-ray crystallography of the binding of the bacterial cell wall trisaccharide NAM-NAG-NAM to lysozyme., Kelly JA, Sielecki AR, Sykes BD, James MN, Phillips DC, Nature. 1979 Dec 20-27;282(5741):875-8. PMID:514367
Page seeded by OCA on Thu Feb 21 19:18:52 2008
