LC-MS spectra. (A) 15N-Galectin-3 C251-CRD (MW ∼15,852 Da) in phosphate buffer (75 mM KH2PO4, 75 mMNaCl, 2 mM EDTA, 5 mM NaN3, 1 mM DTT, 4 mM β-mecaptoethanol at pH 7.4). (B) 15N-Galectin-3 S-propyl-C251-CRD (MW ∼15,926 Da) in phosphate buffer (75 mM KH2PO4, 75mM NaCl, 2 mM EDTA, 5 mM NaN3, no DTT or β-mecaptoethanol at pH 7.4).