Fig 7. Agglutination inhibition assay to test specificity of CV-IIL directly in E. coli cytosol.

Hemagglutination (upper panel) and yeast agglutination inhibition assays (lower panel) with 128× and 2× diluted cytoplasmic extract of E. coli expressing cv-2l gene, respectively. Diluted cytosol was mixed with the monosaccharide in a 1: 1 ratio and incubated for 1 minute at room temperature. 10 μl of the solution was mixed with 10 μl of 5% RBC_0⁺ or 5% yeast suspension and incubated at room temperature for an additional 5 (HI) or 10 (YAI) minutes, mixed again, applied to a glass slide and observed under a Levenhuk microscope. Pictures were taken with a DEM135 camera (Levenhuk).