Biochemistry 2280A Lecture Notes - Lecture 7: Enzyme, Covalent Bond, Cyclohexane Conformation
28 Oct 2016
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Document Summary
Hydrolyzes a polysaccharide found in cell walls of some bacteria: breaks down cell wall by making it weak. An evolutionary older defense strategy found in plants, insects, fungi. Stabilized by 4 disulfide bounds: 2 critical side chains: glutamic and aspartic acid. 1909: laschtschenko discovered anti-bacterial properties of egg white. First enzyme for which detailed mechanism of catalysis was determined. First enzyme whose structure was determined by x-ray crystallography. Chain with repeating sugar units is cleaved. Enzyme forms reversible non-covalent interaction, then reaction occurs and polysaccharide chain is split and product dissociate from the enzyme. Each sugar units acquires a hydroxyl group. Substrate in the picture and comes and binds in active site of the enzyme. Enzyme has 2 acidic residues (asp 52 and glu 35) Glu 35 donates a proton to an oxygen and as a result, the o turns into a hydroxyl group.
