FIGURE 6.

Heparin binding is not changed after mutation of most candidate lysine residues identified via selective labeling. A, linear mode MALDI-TOF mass spectra of WT, selectively acetylated, and biotinylated vaspin. Shown and labeled are the [M + H]⁺ peaks. The mass differences indicate acetylation of ∼31 lysine residues and biotinylation of ∼8 lysine residues. B and C, heparin affinity chromatography of T365R in combination with lysine residues identified using the selective labeling experiment. Elution via a NaCl gradient (black dotted line) was monitored at 220 nm.