9lyz

From Proteopedia

Revision as of 19:54, 29 January 2008 by OCA (Talk | contribs)

(diff) ←Older revision | Current revision (diff) | Newer revision→ (diff)

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 Tue Jan 29 21:54:13 2008