The O-polysaccharide (O-antigen) was released by mild acid hydrolysis of the lipopolysaccharide of Cronobacter sakazakii ATCC 29544(T) (serotype O1) and studied by composition analysis and Smith degradation, in addition to 1D and 2D (1)H and (13)C NMR spectroscopy. The following structure of the pentasaccharide repeating unit of the O-polysaccharide was established: [Formula: see text] where d-Qui3NAcyl stands for 3-(N-acetyl-l-alanyl)amino-3,6-dideoxy-d-glucose. The same composition but a different structure has been reported earlier for the O-polysaccharide of C. sakazakii 3290 [MacLean, L. L.; Pagotto, F.; Farber, J. M.; Perry, M. B. Biochem. Cell Biol.2009, 87, 459-465].

Lipopolysaccharide, O-antigen, 6-dideoxy-d-glucose, bacterial polysaccharide structure, 3-amino-3, Cronobacter sakazakii

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
1,2,2	Ac	175.1	23.3
1,2	aDGalpN	96.2	50.8	68.9	69.9	72.7	62.9
1,3,2	Ac
1,3	xLAla?	177.7	51.2	18.6
1	bDQuip3N	105.4	73.7	57.4	74.4	74.6	18.2
	x?Ery-ol	72.5	71.9	73.5	64.0


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
1,2,2	Ac	-	2.03
1,2	aDGalpN	5.53	4.19	3.72	3.97	3.77	3.73-3.80
1,3,2	Ac
1,3	xLAla?	-	4.42	1.38
1	bDQuip3N	4.67	3.58	3.96	3.29	3.56	1.32
	x?Ery-ol	3.68-4.03	3.79	3.65	3.64-3.76


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
1,2,2	Ac		23.3/2.03
1,2	aDGalpN	96.2/5.53	50.8/4.19	68.9/3.72	69.9/3.97	72.7/3.77	62.9/3.73-3.80
1,3,2	Ac
1,3	xLAla?		51.2/4.42	18.6/1.38
1	bDQuip3N	105.4/4.67	73.7/3.58	57.4/3.96	74.4/3.29	74.6/3.56	18.2/1.32
	x?Ery-ol	72.5/3.68-4.03	71.9/3.79	73.5/3.65	64.0/3.64-3.76

There are 2 chemically distinct structures. Please, select:
Ac(1-2)aDGalpN(1-2)[Ac(1-2)xLAla?(1-3)]bDQuip3N(1-1)xDEry-ol Ac(1-2)aDGalpN(1-2)[Ac(1-2)xLAla?(1-3)]bDQuip3N(1-1)xLEry-ol

SVGMWSMILES3D molIonize

 

CC(=O)N[C@@H](C)C(=O)N[C@H]1[C@H](O)[C@@H](C)O[C@@H](OC[C@H](O)[C@H](O)CO)[C@@H]1O[C@H]1O[C@H](CO)[C@H](O)[C@H](O)[C@H]1NC(C)=O

583.588 g/mol (C₂₃H₄₁N₃O₁₄)