What value do we expect for the pKa of a protein's C-terminal carboxylate? pKa values for free amino acids are quite low (2-3), but it seems to me that this may have something to do with the proximity of a free amine group; I'd expect a higher value (4-ish?) for the peptide's C-terminus.

A quick & lazy search using the term "pka" was stymied by a gazillion references to protein kinase A...

Thanks,

Pat

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Patrick J. Loll, Ph. D.

Professor of Biochemistry & Molecular Biology

Director, Biochemistry Graduate Program

Drexel University College of Medicine

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