5YY4:
reference: Tyrosine Sulfation Restricts the Conformational Ensemble of a Flexible Peptide, Strengthening the Binding Affinity for an Antibody., Miyanabe K, Yamashita T, Abe Y, Akiba H, Takamatsu Y, Nakakido M, Hamakubo T, Ueda T, Caaveiro JMM, Tsumoto K, Biochemistry. 2018 Jul 17;57(28):4177-4185. doi: 10.1021/acs.biochem.8b00592., Epub 2018 Jul 5. PMID: 29936828

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