3VHF:
reference: Atomic structure of the sweet-tasting protein thaumatin I at pH 8.0 reveals the large disulfide-rich region in domain II to be sensitive to a pH change., Masuda T, Ohta K, Mikami B, Kitabatake N, Tani F, Biochem Biophys Res Commun. 2012 Mar 2;419(1):72-6. Epub 2012 Feb 3. PMID: 22326916

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