Structural analysis of capsular polysaccharides expressed by Burkholderia mallei and Burkholderia pseudomallei

摘要

Capsular polysaccharides (CPSs) were isolated from O-polysaccharide deficient strains of Burkholderia mallei and Burkholderia pseudomallei using a modified hot phenol/water extraction procedure. Glycosyl composition, methylation, MALDI-TOF MS analyses as well as ~1H NMR spectroscopy including COSY, TOCSY, NOESY, HMBC and HSQC experiments identified the presence of two distinct CPS antigens in the samples exhibiting the following structures: This study confirms the ability of B. mallei to express a 6-deoxy-heptan CPS and represents the first report of a mannan CPS being expressed by these bacterial pathogens.