A polysaccharide containing D-Gal, D-GalNAc, 3-(L-2-acetoxypropionamido)-3,6-dideoxy-D-galactose (approximately 80%) and 3-(L-2-hydroxypropionamido)-3,6-dideoxy-D-galactose (approximately 20%) was isolated by mild acid hydrolysis, followed by gel-permeation chromatography, from the phenol-soluble lipopolysaccharide (phenol/water extracted) derived from Acinetobacter strain 94. The polysaccharide, characterised by means of monosaccharide analyses, partial acid hydrolysis, and NMR studies, consisted of a branched tetrasaccharide repeating unit, as depicted below, in which Fucp3Nacyl represents 3-(L-2-hydroxypropionamido)-3,6-dideoxy-D-galactose, in which approximately 80% of the acyl residues are O-acetylated. These Fucp3N derivatives and an O-acetylated acyl group are therefore constituents of bacterial LPS, but to our knowledge are not present in any other natural carbohydrates. [sturcture: see text]

Lipopolysaccharide, LPS, DNA, strain, structural, polysaccharide, O-antigen, group, O-antigenic, O-antigenic polysaccharide, acid, Acinetobacter, 6-dideoxy-D-galactose, polysaccharides, structural studies, 3-amino-3, 2-acetoxypropionyl, amide-linked, phenol soluble

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
3,4,4,3,2	80%Ac	?	20.48
3,4,4,3	lSLac	?	68.19	19.97
3,4,4	aDFucp3N	100.26	66.61	51.35	71.43	67.78	15.37
3,4,2	Ac
3,4	bDGalpN	102.49	52.89	70.88	77.48	75.45	60.75
3	aDGalp	95.63	67.16	80.39	76.90	70.76	60.93
2	Ac
	bDGalpN	103.68	51.23	76.05	64.30	75.03	61.49


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
3,4,4,3,2	80%Ac	-	2.22
3,4,4,3	lSLac	-	5.18	1.53
3,4,4	aDFucp3N	5.00	3.93	4.34	3.87	4.51	1.21
3,4,2	Ac
3,4	bDGalpN	5.02	4.09	3.88	4.09	3.81	3.90-3.93
3	aDGalp	5.15	3.84	3.91	4.43	3.87	3.76-3.84
2	Ac
	bDGalpN	4.70	4.23	3.89	4.23	3.78	3.86-3.86


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
3,4,4,3,2	80%Ac		20.48/2.22
3,4,4,3	lSLac		68.19/5.18	19.97/1.53
3,4,4	aDFucp3N	100.26/5.00	66.61/3.93	51.35/4.34	71.43/3.87	67.78/4.51	15.37/1.21
3,4,2	Ac
3,4	bDGalpN	102.49/5.02	52.89/4.09	70.88/3.88	77.48/4.09	75.45/3.81	60.75/3.90-3.93
3	aDGalp	95.63/5.15	67.16/3.84	80.39/3.91	76.90/4.43	70.76/3.87	60.93/3.76-3.84
2	Ac
	bDGalpN	103.68/4.70	51.23/4.23	76.05/3.89	64.30/4.23	75.03/3.78	61.49/3.86-3.86

The spectrum also has 2 signals at unknown positions (not plotted).

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

*O[C@@H]1[C@@H](O)[C@@H](O[C@@H]2[C@@H](NC(C)=O)[C@H](*)O[C@H](CO)[C@@H]2O)O[C@H](CO)[C@@H]1O[C@@H]1O[C@H](CO)[C@H](O[C@H]2O[C@H](C)[C@H](O)[C@H](NC(=O)[C@H](C)OC(C)=O)[C@H]2O)[C@H](O)[C@H]1NC(C)=O

827.787 g/mol (C₃₃H₅₃R₂N₃O₂₁, R = next and previous repeats, not counted in mol weight)