Different rhamnose-rich polysaccharides (RRP) were identified in the cell envelope of the Gram-positive bovine mastitis isolate Streptococcus dysgalactiae 2023. Structural investigations of the 1D and 2D nuclear magnetic resonance experiments as well as chemical analyses identified as main components l-Rha and d-GalNAc. Two main RRP were characterized, namely 1 being composed of the repeating unit {→3)-α-L-Rhap-(1→2)-[α-D-GalpNAc-(1→3)-β-D-GalpNAc-(1→3)-]α-l-Rhap-(1} and 2 possessing the repeat [→2)-α-L-Rhap-(1→3)-α-L-Rhap-(1→].

isolate, structural, polysaccharide, Streptococcus, repeating unit, cell, Research, chemical, polysaccharides, biochemistry, medicine, nuclear, nuclear magnetic resonance, resonance, component, NMR analysis, cell envelope, Gram-positive, rhamnan, bovine, lung, envelope, mastitis, Streptococcus dysgalactiae, allergy, Asthma

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
2	aLRhap	102.39	70.90	78.13	72.67	70.10	17.80
3,3,2	Ac	175.69	?
3,3	aDGalpN	94.58	50.50	68.83	69.57	70.89	62.34
3,2	Ac	175.29	?
3	bDGalpN	103.88	52.09	75.86	70.77	75.89	62.13
	aLRhap	102.14	77.69	80.98	72.93	70.43	17.94


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
2	aLRhap	5.21	4.09	3.86	3.56	3.73	1.26
3,3,2	Ac	-	2.04
3,3	aDGalpN	5.07	4.20	3.78	4.00	4.10	3.77-3.77
3,2	Ac	-	2.02
3	bDGalpN	4.74	4.08	3.79	4.11	3.83	3.83-3.85
	aLRhap	5.10	4.30	4.00	3.54	3.85	1.32


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
2	aLRhap	102.39/5.21	70.90/4.09	78.13/3.86	72.67/3.56	70.10/3.73	17.80/1.26
3,3,2	Ac		?/2.04
3,3	aDGalpN	94.58/5.07	50.50/4.20	68.83/3.78	69.57/4.00	70.89/4.10	62.34/3.77-3.77
3,2	Ac		?/2.02
3	bDGalpN	103.88/4.74	52.09/4.08	75.86/3.79	70.77/4.11	75.89/3.83	62.13/3.83-3.85
	aLRhap	102.14/5.10	77.69/4.30	80.98/4.00	72.93/3.54	70.43/3.85	17.94/1.32

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](C)O[C@@H](O[C@H]2[C@H](*)O[C@@H](C)[C@H](O)[C@H]2O[C@@H]2O[C@H](CO)[C@H](O)[C@H](O[C@H]3O[C@H](CO)[C@H](O)[C@H](O)[C@H]3NC(C)=O)[C@H]2NC(C)=O)[C@@H]1O

698.672 g/mol (C₂₈H₄₆R₂N₂O₁₈, R = next and previous repeats, not counted in mol weight)

Different rhamnose-rich polysaccharides (RRP) were identified in the cell envelope of the Gram-positive bovine mastitis isolate Streptococcus dysgalactiae 2023. Structural investigations of the 1D and 2D nuclear magnetic resonance experiments as well as chemical analyses identified as main components l-Rha and d-GalNAc. Two main RRP were characterized, namely 1 being composed of the repeating unit {→3)-α-L-Rhap-(1→2)-[α-D-GalpNAc-(1→3)-β-D-GalpNAc-(1→3)-]α-l-Rhap-(1} and 2 possessing the repeat [→2)-α-L-Rhap-(1→3)-α-L-Rhap-(1→].

isolate, structural, polysaccharide, Streptococcus, repeating unit, cell, Research, chemical, polysaccharides, biochemistry, medicine, nuclear, nuclear magnetic resonance, resonance, component, NMR analysis, cell envelope, Gram-positive, rhamnan, bovine, lung, envelope, mastitis, Streptococcus dysgalactiae, allergy, Asthma

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
2	aLRhap	103.44	70.98	78.49	74.66	70.39	17.80
	aLRhap	101.87	79.20	71.10	73.30	70.34	18.03


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
2	aLRhap	4.96	4.17	3.85	3.55	3.76	1.27
	aLRhap	5.19	4.07	3.95	3.52	3.83	1.32


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
2	aLRhap	103.44/4.96	70.98/4.17	78.49/3.85	74.66/3.55	70.39/3.76	17.80/1.27
	aLRhap	101.87/5.19	79.20/4.07	71.10/3.95	73.30/3.52	70.34/3.83	18.03/1.32

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

*O[C@@H]1[C@@H](O)[C@H](C)O[C@@H](O[C@H]2[C@H](*)O[C@@H](C)[C@H](O)[C@H]2O)[C@@H]1O

292.284 g/mol (C₁₂H₂₀R₂O₈, R = next and previous repeats, not counted in mol weight)