CHE 4341 Lecture Notes - Lecture 11: Hydrolysis, Oxyanion, Antigen
Document Summary
Destroys polysaccharide chains of bacterial cell walls. Hydrolyzes the glycosidic bond b/t c-1 of n-acetyl muramic. Lysozyme acid (nam) and c-4 of n-acetyl glucosamine (nag) D. c. phillips hew lysozyme w/a bound nag6 substrate. Bc lysozyme breaks a glycosidic bond, it is a glycosidase. Observed distortion of d sugar in active site to half chair. Determined lysozyme binds 6 carbohydrate residues in its active site. Saw important asp (asp 52) & glu (glu 35) in active site. Lysozyme employs ts state stabilization / preferential binding of strained. Ts in its catalytic mech: correct position to stabilize developing carbocation. D residue has to be distorted to 1/2 chair to orient o lone pair in. Lysozyme stabilizes distorted 1/2 chair (ts stabilization) Ts stabilization (of residue d in distorted 1/2 chair) Stable analogs that resemble ts conformation of a rxn. Bind very tightly to the active site of enzyme. Evidence for enzyme preferentially binding & stabilizing ts.
