Structural Analysis of the Extracellular Polysaccharide Produced bySphaerotilus natans

Abstract

An extracellular polysaccharide (EPS) was recovered and puriˆed from the culture ‰uid of a sheathed bacterium, Sphaerotilus natans. Glucose, rhamnose, and aldobiouronic acid were detected in the acid hydrolysate of EPS by thin-layer chromatography (TLC). The aldobiouronic acid was found to be composed of glucuronic acid and rhamnose by TLC and gas-liquid chromatography analyses of the corresponding neutral disaccharide. The structure of EPS was identiˆed by methylation linkage analysis and nuclear magnetic resonance. Additionally, partial acid hydrolysates of EPS were prepared and put through fast atom bombardment-mass spectrometry to determine the sugar sequence of EPS. The resulting data showed that EPS produced by S. natans is a new gellan-like polysaccharide constructed from a tetrasaccharide repeating unit, as shown below.

Structural analysis of the sheath of a sheathed bacterium, Leptothrix cholodnii

“…The m-hydroxylbiphenyl reaction was carried out for the qualitative analysis of uronic acid according to a previously described method [23,24]. Prior to the reaction, 1 mg of a sample was hydrolyzed in 1 ml of 2.0 M TFA at 100 • C for 2 h. The amounts of the amino and neutral sugars were measured by gas liquid chromatography (GLC).…”

“…The sample for the GLC analysis was hydrolyzed in the manner described above. The hydrolysate was derivatized to alditol acetate and injected into the GLC instrument (GC-14B, Shimadzu) as described in our previous papers [15,23]. The enantiomeric configurations of the sugars were identified by the formation of the (-)-2-butylglycosides according to the method of Gerwig et al [25,26].…”

“…The enantiomeric configurations of the sugars were identified by the formation of the (-)-2-butylglycosides according to the method of Gerwig et al [25,26]. The methylation analysis was done by the previously described method [15,23].…”

Sugar composition and FT-IR analysis of exopolysaccharides produced by microbial isolates from paper mill slime deposits

“…The few detailed EPS structures currently known are the ones produced by Brevundimonas vesicularis (Verhoef et al, 2002), Raoultella terrigena (Dutton and Mackie, 1978), Methylobacterium sp. (Verhoef et al, 2003), and Sphearothilus natans (Takeda et al, 2002).…”

Paenibacillus hodogayensis sp. nov., capable of degrading the polysaccharide produced by Sphaerotilus natans

“…S. natans forms a sheath (Eikelboom, 1975;Takeda et al, 1998Takeda et al, , 2003van Veen et al, 1978) and a slimy extracellular polysaccharide (EPS) (Gaudy & Wolfe, 1962). The EPS is a straight-chain acidic polysaccharide (Takeda et al, 2002c) and is tightly associated with the sheath (Gaudy & Wolfe, 1962;Takeda et al, 2002b). The bulking effects of S. natans may due to the production of the sheath and the EPS.…”