. Author manuscript; available in PMC: 2012 Sep 21.

Published in final edited form as: Bioconjug Chem. 2011 Aug 25;22(9):1811–1823. doi: 10.1021/bc2002117

Table 1. DMB-derivatization of sialic acids reveals that SiaDAz(2me) and SiaDAz(3me) effectively compete with endogenous sialic acid for incorporation into glycoconjugates.

Jurkat cells were cultured with the indicated compounds, harvested and fractionated. Sialic acids were derivatized by DMB and separated by reverse phase HPLC with fluorescence detection (see Figures S4–S6). Peaks were integrated to derive the percentages of Neu5Ac and other sialic acids. Multiple values indicate results from independent experiments. N.D. indicates that a peak corresponding to SiaDAz(4me) could not be identified.

compound added	fraction analyzed	% of total sialic acid
compound added	fraction analyzed	Neu5Ac	SiaDAz (2me, 3me, or 4me)
no added sugar	cytosol	100	0
no added sugar	membrane	100	0
Ac₄ManNAc	cytosol	100	0
Ac₄ManNAc	membrane	100	0
Ac₄ManNDAz(2me)	cytosol	15	85
Ac₄ManNDAz(2me)	membrane	26	74
Ac₄ManNDAz(3me)	cytosol	63, 70	37, 30
Ac₄ManNDAz(3me)	membrane	92, 96	8, 4
Ac₄ManNDAz(4me)	cytosol	100	N.D.
Ac₄ManNDAz(4me)	membrane	100	N.D.