The image below shows the structure of an enzyme in its tertiary form. Its active site contains Histidine and Aspartate residues that are essential for catalytic function. Answer the two questions below. a) Describe the forces that stabilise each secondary structure in this enzyme, as well as the types of residues that would make up the internal core of the protein. b) The codon that codes for the Histidine in the active site has undergone a mutation and now codes for a Tyrosine residue instead. Describe what type of catalytic role the Histidine and Aspartate residue normally play, and describe how the substitution of the Histidine for the Tyrosine residue would alter the enzyme's catalytic function.
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Forces that stabilize secondary structures in the enzyme: - Alpha-helices are stabilized by hydrogen bonds between the carbonyl oxygen of one amino acid residue and the amide hydrogen of another residue four positions away in the polypeptide chain. - Beta-sheets Show more…
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