FIGURE 6.

SDS-PAGE separated LOS from 7946 and its Δlst and ΔlgtB mutants compared with LOS from 8026 and 1291wt, 1291a, 1291c, and 1291d. LOS were electrophoresed through 27 cm of 13.1% polyacrylamide gel and visualized with silver stain. 7946 and 8026 both make two LOS; the slower migrating molecule (upper band) is the sialylated LOS, and this glycoform is absent from 7946Δlst, which has the same electrophoretic mobility as 1291wt. 7946ΔlgtB has the same electrophoretic mobility as 1291a and migrates more slowly than 1291c.