Figure 2. The T-tract length alters sLex-receptor binding activity by affecting sabA mRNA levels in H. pylori.

A) SabA protein expression analysis in variants of SMI109 harboring different T-tract lengths. Image shows one representative immunoblot with α-SabA antibodies used for the quantification. Expression levels were normalized to expression of the AlpB protein before comparison (Fig. S10B). Data are presented in the bar diagram, as described in Fig. 1A, with the expression in the T₁₃ (wt) variant set to 1. Stars indicate significant differences from T₁₃-variant, * p<0.05, ** p<0.01, ns = non significant. B) Binding to soluble ¹²⁵I-sLex-receptor conjugates of the same set of T-variants as in Fig. 2A. The data are presented as in Fig. 1A, with the binding of the T₁₃-variant set to 1. Stars mark significant differences from T₁₃-variant, see Fig. 2A. C) RT-qPCR analysis of sabA mRNA levels in T-variants of SMI109. Data are presented as in Fig. 1B, with the mRNA levels in the T₁₃-variant (wt) set to 1. The upper images show result from one semi-quantitative PCR analysis using primers for sabA-1 and rrnA-2. D) Binding of FITC-labeled SMI109 T-variants (T₉, T₁₃ and T₁₈) to human gastric tissue sections. SMI109 ΔsabA mutant was included as a negative control. Images were taken with 100× magnification. For all analyses in Fig. 2, bacteria were grown on plate prior to the experiment, as described in Materials and Methods.