Creighton TE, 1993
Creighton presents a complete set of pK values in his text Proteins: structures and molecular properties (1). The data used to generate these values are from a variety of authors and span both model compound and short peptide data (2-4). Creighton does warn that the pK values of the α-carboxyl and α-amino groups are highly dependent on the identity of the terminal amino acid.
Amino acid pK values from Creighton TE, 1993 (1).