Occurrence, Location, and Linkages of KDO Residues in Bacterial Polysaccharides

Occurrence, Location, and Linkages of KDO Residues in Bacterial Polysaccharides 

Originally, the periodate -TBA assay was recommended by Warav-dekar and Saslaw10 for the determination of 2-deoxy sugars. In this ap- 

The TBA assay for 3-deoxyglyc-2-ulosonic acids, used by Weissbach and Hurwitz11 to determine 3-deoxy-D-arabino-2-heptulosonic acid, was subsequently applied by Warren13 and by Aminoff14 to the analysis ofN-acetylneuraminic acid (NeuAc, 5 see Fig. 4). The formation of the 3-formylpyruvate-derived chromophore 4 in the periodate 

Molar Extinction Coefficients of the TBA Chromophore (4) in Different Solvents 

Warren,13 the KDO moieties usually give a TBA response equivalent to that obtained after acid hydrolysis. Apparently, both the ketosidic and aglyconic linkages of KDO are cleaved during such treatment, so that KDO reacts essentially as the free 3-deoxyglyculosonic acid. Due to partial destruction of KDO by acid,23-25 the color yield is less than optimal (see Fig. 5b, d). 

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