Acid dissociation constants of glycopeptides.

  title={Acid dissociation constants of glycopeptides.},
  author={Brian M. Austen and Richard D Marshall},
  journal={The Biochemical journal},
  volume={163 1},
Glycopeptides containing mainly four amino acid residues in the sequence Asn-Leu-Thr-Ser, with small amounts of additional amino acid residues, were isolated from enzymic hydrolysates of hen's-egg albumin. Heterogeneity of the carbohydrate moiety was confirmed. Acid-base titrations showed that the alpha-amino group has a pKa value of 6.43 at 25 degrees C. The standard free engery and entropy changes associated with the ionization at 25 degrees C were 37.2kJ-mol-1 and -0.014kJ-mol-1- K-1… CONTINUE READING