What is the pKa value of the R-group of Tyrosine?

The pKa value of the R-group of Tyrosine is approximately 10. This specific pKa is significant as it reflects the ability of the hydroxyl group (-OH) on the aromatic side chain of Tyrosine to donate a proton (H+). At physiological pH (around 7.4), the R-group is primarily in its uncharged form, which means it can participate in hydrogen bonding and contribute to the overall structure and function of proteins.

Understanding the pKa value is crucial because it helps predict the behavior of Tyrosine under different pH conditions. When the pH of the environment approaches the pKa value, the balance between protonated and deprotonated forms shifts, which can have important implications for enzyme activity, protein structure, and interactions with other molecules. Therefore, the pKa of 10 indicates that Tyrosine can play a role in various biochemical processes, especially in active sites of enzymes or in binding interactions where charge and polarity are important.