Table 2.

GC-MS analysis of TMS methyl glycoside sugar derivatives obtained from S. acidocaldarius S-layer glycoprotein. Note that for experimental reasons GlcNAc recoveries are always poor in sugar analysis experiments. We consider it likely that this is the reason for the GlcNAc:Mannose ratio being much lower than expected from the LC-ES/MS/MS data, although we cannot rule out the possibility that other mannose-containing polymers are present in the sample.

Elution time (min)	Characteristic fragment ions	Assignment	Relative amounts
12.85	204, 217, 305, 361	Man	1
14.62	204, 217, 305, 361	Glc	0.38
18.04	173, 259, 314	GlcNAc	0.22