FIGURE 4.

Mass spectra of the Hyp-linked arabinogalactan of Amb a 4. A, MALDI spectrum with mainly [M+Na]⁺ ions. [M+K]⁺ and [M+H]⁺ ions are not annotated. (B) Fragment spectrum obtained by ESI-MSMS of the [M+H]⁺ ion of the Ara₇-Gal-Hyp glycopeptide.