| 1VWJ: Streptavidin-Cyclo-[5-S-Valeramide-Hpqgppc]K-Nh2, Ph 2.5, I2 reference: In crystals of complexes of streptavidin with peptide ligands containing the HPQ sequence the pKa of the peptide histidine is less than 3.0., Katz BA, Cass RT, J Biol Chem 1997 May 16;272(20):13220-8. PMID: 9148939 |
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