The sulfated polysaccharides are of study interest due to their high structural diversity and broad spectrum of biological activity including antitumor properties. In this paper, we report on the structural analysis of sulfated O-specific polysaccharide (OPS) and in vitro anticancer activity of O-deacylated lipopolysaccharide (DPS) of the marine-derived bacterium Poseidonocella sedimentorum KMM 9023T achieved by a multidisciplinary approach (chemical analysis, NMR, MS, and bioassay). The OPS is shown to include two rare monosaccharide derivatives: 3-deoxy-9-O-methyl-d-glycero-d-galacto-non-2-ulosonic acid (Kdn9Me) and 3-O-acetyl-2-O-sulfate-d-glucuronic acid (D-GlcA2S3Ac). The structure of polysaccharide moiety of a previously unknown carbohydrate-containing biopolymer is established: →4)-α-Kdnp9Me-(2→4)-α-d-GlcpA2S3Ac-(1→. From a biological point of view, we demonstrate that DPS of the P. sedimentorum KMM 9023T has no cytotoxicity and inhibits colony formation of human HT-29, MCF-7 and SK-MEL-5 cells in a dose-dependent manner. The investigated polysaccharide is the second glycan isolated from the bacteria of the genus Poseidonocella: previously we studied the OPS of P. pacifica KMM 9010T (Kokoulin et al., 2017). Both polysaccharides are sulfated and contain rare residues of ulosonic acids. Thus, obtained findings provide a new knowledge about kinds and antitumor properties of sulfated polysaccharides and can be a starting point for further investigations of mechanisms of anticancer action of carbohydrate-containing biopolymers from marine Gram-negative bacteria.

O-polysaccharide, Marine bacterium, anticancer activity, Poseidonocella sedimentorum, Sulfate 3-deoxy-d-glycero-d-galacto-non-2-ulosonic acid

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

[*]O[C@H]1C[C@](O[C@@H]2[C@@H](C(=O)O)O[C@H]([*])[C@H](OS(=O)(=O)O)[C@H]2OC(C)=O)(C(=O)O)O[C@@H]([C@H](O)[C@H](O)COC)[C@@H]1O

562.455 g/mol (C₁₈H₂₆R₂O₁₈S, R = next and previous repeats, not counted in mol weight)

The sulfated polysaccharides are of study interest due to their high structural diversity and broad spectrum of biological activity including antitumor properties. In this paper, we report on the structural analysis of sulfated O-specific polysaccharide (OPS) and in vitro anticancer activity of O-deacylated lipopolysaccharide (DPS) of the marine-derived bacterium Poseidonocella sedimentorum KMM 9023T achieved by a multidisciplinary approach (chemical analysis, NMR, MS, and bioassay). The OPS is shown to include two rare monosaccharide derivatives: 3-deoxy-9-O-methyl-d-glycero-d-galacto-non-2-ulosonic acid (Kdn9Me) and 3-O-acetyl-2-O-sulfate-d-glucuronic acid (D-GlcA2S3Ac). The structure of polysaccharide moiety of a previously unknown carbohydrate-containing biopolymer is established: →4)-α-Kdnp9Me-(2→4)-α-d-GlcpA2S3Ac-(1→. From a biological point of view, we demonstrate that DPS of the P. sedimentorum KMM 9023T has no cytotoxicity and inhibits colony formation of human HT-29, MCF-7 and SK-MEL-5 cells in a dose-dependent manner. The investigated polysaccharide is the second glycan isolated from the bacteria of the genus Poseidonocella: previously we studied the OPS of P. pacifica KMM 9010T (Kokoulin et al., 2017). Both polysaccharides are sulfated and contain rare residues of ulosonic acids. Thus, obtained findings provide a new knowledge about kinds and antitumor properties of sulfated polysaccharides and can be a starting point for further investigations of mechanisms of anticancer action of carbohydrate-containing biopolymers from marine Gram-negative bacteria.

O-polysaccharide, Marine bacterium, anticancer activity, Poseidonocella sedimentorum, Sulfate 3-deoxy-d-glycero-d-galacto-non-2-ulosonic acid

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6	C7	C8	C9
4,9	Me
4	aXKdnp	176.0	101.0	38.4	77.1	68.6	74.8	69.8	71.0	74.8
2	S
	aDGlcpA	94.6	78.2	71.3	75.3	74.1	177.0


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6	H7	H8	H9
4,9	Me
4	aXKdnp	-	-	1.60-2.78	3.63	3.64	3.64	3.71	4.10	3.64-3.78
2	S
	aDGlcpA	5.30	4.14	3.83	4.11	4.19	-


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6	C7/H7	C8/H8	C9/H9
4,9	Me
4	aXKdnp			38.4/1.60-2.78	77.1/3.63	68.6/3.64	74.8/3.64	69.8/3.71	71.0/4.10	74.8/3.64-3.78
2	S
	aDGlcpA	94.6/5.30	78.2/4.14	71.3/3.83	75.3/4.11	74.1/4.19	

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

[*]O[C@H]1C[C@](O[C@@H]2[C@@H](C(=O)O)O[C@H]([*])[C@H](OS(=O)(=O)O)[C@H]2O)(C(=O)O)O[C@@H]([C@H](O)[C@H](O)COC)[C@@H]1O

520.418 g/mol (C₁₆H₂₄R₂O₁₇S, R = next and previous repeats, not counted in mol weight)