Table 2.

Mass spectrometric analysis of the O- and N-deacylated core-LA carbohydrate backbone of Pst DC3000 ΔwbpL. Summary of calculated monoisotopic neutral masses and observed molecular masses [Da] in the OS-HyKOH preparation, the corresponding MS spectrum is depicted in Figure 3a. Accuracy of the measurement is stated as Δppm; anh = anhydro.

Molecule	Composition	Calculated Mass [Da]	Observed Mass [Da]	Error [ppm]	HPAEC *
4	Kdo2Hep2Hex16dHex1HexN3P5	2033.403	2033.403	0.0	pool 4
5	Kdo2Hep2Hex2HexN3P5	2049.398	2049.397	−0.5	pool 3
6	Kdo1Hep2Hex26dHex1HexN4P5	2136.466	2136.466	0.0	pool 1
3	Kdo2Hep2Hex26dHex1HexN3P5	2195.456	2195.455	−0.5	pool 4
7	Kdo2Hep2Hex2HexN4P5	2210.467	2210.466	−0.5	pool 3
8	Kdo2Hep2Hex26dHex1HexN3P6	2275.422	2275.422	0.0	pool 6
1	Kdo2Hep2Hex26dHex1HexN4P5	2356.524	2356.525	0.4	pool 2/3
10anh	Kdo2Hep2Hex26dHex1HexN3P5[12:0(3-OH)]–H2O	2375.607	2375.606	−0.4	**
10	Kdo2Hep2Hex26dHex1HexN3P5[12:0(3-OH)]	2393.618	2393.617	−0.4	**
9	Kdo3Hep2Hex2HexN4P5	2430.525	2430.523	−0.8	pool 4
2	Kdo2Hep2Hex26dHex1HexN4P6	2436.491	2436.490	−0.4	pool 5
11anh	Kdo2Hep2Hex26dHex1HexN4P5[12:0(3-OH)]–H2O	2536.676	2536.679	1.2	**
11	Kdo2Hep2Hex26dHex1HexN4P5[12:0(3-OH)]	2554.686	2554.689	1.2	**
12anh	Kdo2Hep2Hex26dHex1HexN4P6[12:0(3-OH)]–H2O	2616.642	2616.644	0.8	**
12	Kdo2Hep2Hex26dHex1HexN4P6[12:0(3-OH)]	2634.653	2634.654	0.4	**

* see Figure S1, ** these monoacylated molecules elute at later retention times, and pools were of minor yield.