The $\mathrm{p}K_{\mathrm{a}}$ of the functional groups in L-glutamic acid (shown below on the right) from left to right are $4.1$, $9.5$, and $2.1$. Predict the $\mathrm{p}K_{\mathrm{a}}$ values of B-glutamic acid (below on the left).

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I am not sure on the answer and I am just guessing here.

The $\mathrm{p}K_{\mathrm{a}}$ value for the $\ce{COOH}$ group on the right will increase at it won't be stabilised by the amino group any more. The $\mathrm{p}K_{\mathrm{a}}$ of the $\ce{COOH}$ on the left won't really change.I am guessing that the $\mathrm{p}K_{\mathrm{a}}$ of the amino group will decrease. That is a complete guess.

Can anyone please explain how exactly the amino group effects the stability of the $\ce{COO-}$ group and also how the $\ce{COOH}$ group effects the stability of the $\ce{NH3+}$ group.


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