🤓 Based on our data, we think this question is relevant for Professor Ravi's class at LEHMAN-CUNY.
Recall that if pH > pKa, the group will be deprotonated and
if pH < pKa, group gets protonated
For histidine, pKa of -COOH is 1.82 while -NH2 is 9.17
An amino acid backbone is drawn below. Draw the histidine side chain structure for the predominant ionization state of histidine at pH 8.0.
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