Relative abundance of phosphorus, glycerol and glucosamines in S. hygroscopicus LTA as determined by biochemical and NMR analyses.

aRelative quantification of P and amino sugars (i.e. GlcN+GlcNAc) was performed by colorimetric assays, the amount of P being fixed to 1. The ratio Gro/amino sugars was determined by GC but is overestimated because of partial amino sugar degradation during strong acid hydrolysis.bRelative quantification of the different Gro derivatives was performed by integration of the corresponding H-2/C-2 cross peak on 1H-13C HMQC spectrum (Figure 3G).cThese values perfectly fit with the GlcN/GlcNAc ratio of 3.7/1 as determined by integration of the corresponding anomeric signals (Figure 3D).Gro, glycerol; GlcNAc, N-acetyl-glucosamine; GlcN, glucosamine; P, phosphate; P-1-Gro-3-P, P-2-Gro-3-P, 1,3- and 2,3-diphospho-glycerol units respectively.

a 采用比色法对磷酸盐（phosphate，P）与氨基糖（即葡萄糖胺glucosamine，GlcN+N-乙酰葡糖胺N-acetyl-glucosamine，GlcNAc）进行相对定量，实验中固定磷酸盐的相对含量为1。通过气相色谱法（Gas Chromatography，GC）测定甘油（glycerol，Gro）与氨基糖的比值，但该比值存在高估，原因是强酸水解过程中部分氨基糖发生降解。
b 对各类甘油（Gro）衍生物的相对定量，通过积分1H-13C 异核多量子相干谱（Heteronuclear Multiple Quantum Coherence，HMQC）中对应的H-2/C-2交叉峰完成，对应图谱见图3G。
c 该数值与通过积分对应异头信号（对应图谱见图3D）测得的GlcN/GlcNAc比值3.7/1完全吻合。
注：Gro即甘油（glycerol）；GlcNAc即N-乙酰葡糖胺（N-acetyl-glucosamine）；GlcN即葡萄糖胺（glucosamine）；P即磷酸盐（phosphate）；P-1-Gro-3-P、P-2-Gro-3-P分别对应1,3-二磷酸甘油基与2,3-二磷酸甘油基单元。