Structure of the O-polysaccharide of Proteus mirabilis O38 containing 2-acetamidoethyl phosphate and N-linked D-aspartic acid.
The O-antigen of Proteus mirabilis O38 was found to be unique among bacterial polysaccharides and to have the following structure: [carbohydrate structure in text] where D-Qui4N(Ac-D-Asp) is 4-(N-acetyl-D-aspart-4-ylamino)-4,6-dideoxy-D-glucose and AcEtnP is 2-acetamidoethyl phosphate. Neither of these entities have been hitherto found in natural polysaccharides. Structural studies were performed using 1D and 2D NMR spectroscopy, including experiments run in an H2O/D2O mixture to reveal correlations for NH protons. In addition, dephosphorylation, carboxyl reduction and selective cleavages were applied. Solvolysis of the polysaccharide with anhydrous HF gave an alpha-D-GlcNAc-(1-->3)-D-Qui4N(Ac-D-Asp) disaccharide. Solvolysis with trifluoromethanesulfonic (triflic) acid afforded D-GlcNAc6(AcEtnP), thus showing the suitability of this reagent for the preparation of phosphorylated sugar derivatives.
ND Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, Moscow 119991, Russia.
Anna N
AN
Kondakova
Sof'ya N
SN
Senchenkova
Andrei I
AI
Gremyakov
Alexander S
AS
Shashkov
Yuriy A
YA
Knirel
Rafal
R
Fudala
Wieslaw
W
Kaca
D000586:Amination; D001224:Aspartic Acid / Q000737:chemistry*; D002240:Carbohydrate Sequence; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010766:Phosphorylation; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D011513:Proteus mirabilis / Q000737:chemistry*; D013403:Sugar Phosphates / Q000032:analysis* / Q000737:chemistry
D011134:Polysaccharides; D013403:Sugar Phosphates; D001224:Aspartic Acid