Fig 7. SDS-PAGE of S. marcescens CPS and LPS from five KL clades.

Total cell-associated polysaccharides were isolated from S. marcescens strains following overnight culture. (A) Purified polysaccharides were resolved on 7.5% SDS-PAGE gels and visualized by Alcian Blue staining. The molecular weights (kDa) of pre-stained protein standards (MW standard) are indicated. (B) Total cell-associated polysaccharides were also electrophoresed on 4–20% gradient SDS-PAGE gels. LPS was visualized using the Pro-Q Emerald 300 Liposaccharide Gel Stain Kit with purified LPS from E. coli serving as a positive control. The region containing the characteristic O-antigen laddering pattern is indicated.