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Purification and Visualization of Lipopolysaccharide from Gram-negative Bacteria by Hot Aqueous-phenol Extraction
Published on: May 28, 2012
Glycerolphosphate-containing cell wall polysaccharides from Streptococcus sanguis
Journal of Bacteriology
|November 1, 1974
Summary
Six unique cell wall polysaccharides from Streptococcus sanguis were purified and characterized. Formamide extraction appears to break phosphodiester bonds, yielding varied polysaccharide structures from a common precursor.
Area of Science:
- Microbiology
- Biochemistry
- Glycobiology
Background:
- Streptococcus sanguis possesses complex cell wall structures.
- Understanding bacterial cell wall composition is crucial for antimicrobial development.
Purpose of the Study:
- To purify and characterize novel glycerolphosphate-containing tetraheteroglycans from Streptococcus sanguis.
- To investigate the structural integrity and origin of these polysaccharides.
Main Methods:
- Purification using alcohol/acetone precipitation and Sephadex G-75/DEAE-cellulose chromatography.
- Purity assessment via analytical disc gel electrophoresis and immune double diffusion.
- Structural analysis including polyacrylamide gel electrophoresis and formamide treatment.
Main Results:
- Six pure tetraheteroglycans (a, b-1 to b-5) were isolated.
- Polysaccharides shared similar molar ratios of l-rhamnose, d-glucose, and N-acetyl d-glucosamine but differed in glycerol and phosphate content.
- Formamide treatment induced changes in polysaccharide mobility, suggesting phosphodiester bond breakage.
Conclusions:
- The isolated polysaccharides represent fragments of a common cell wall polysaccharide.
- Formamide extraction at high temperatures can lead to artifactual degradation via phosphodiester bond cleavage.
- Preliminary data suggest l-rhamnose as the terminal sugar and glycerol linked via a phosphodiester bond.
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