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Titration Curves: Titration of Tyrosine

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1) Plot the pH titration of tyrosine, whose structure is shown attached at pH = 7.0. Show:
a) The pH value at each equivalence points and each 1/2 equivalence point
b) The charge at each equivalence and 1/2 equivalence point
c) The isoelectric point of the amino acid and give its value
d) The approximate shape of the titration curve

2) Draw the structure of tyrosine at pH = 9.59.

Look at the diagrams in the document.

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The pH titration of tyrosine is plotted and its structure is drawn.

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1. If the active site of a dipeptidase contains a glutamic acid residue (pKa 3.3) and a histidine residue (pKa 6.7), both of which must be charged for the substrate to bind, what is the optimal pH for substrate binding?

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