CBMs within BgaA directly bind epithelial cells.

<p>(A) Binding of D562 cells to immobilized recombinant CBM71-1. A range of concentrations (2.5–20 µg ml⁻¹) of CBM71-1 were immobilized on the bottom of a 96 well plate. D562 cells pretreated with 0.002 Unit ml⁻¹<i>C. perfringens</i> sialidase (<i>Cp</i>Sia) with or without 0.054 µM <i>Sp</i>BgaA146-990 (<i>Sp</i>BgaA) were allowed to adhere to the plate. Adherence to control wells coated with 1 mg ml⁻¹ of BSA was subtracted from the data (maximum 22 cells per well). Asterisks indicate significant differences in the number of adherent D562 cells following pretreatment with sialidase and sialidase plus <i>Sp</i>BgaA146-990. (B) Binding of D562 cells to immobilized recombinant CBM71-2. As in (A) except using CBM71-2. (C) Adherence of <i>S. pneumoniae</i> strain R6 and R6BgaAW1514A,W1864A to D562 cells. Asterisks indicate significant differences in adherence of R6 and R6BgaAW1514A,W1864A. Data are the mean ± SD of three independent experiments each performed in triplicate. Statistically significant differences were assessed using a two-tailed Student's <i>t</i>-test. * p≤0.04, ** p≤2.00×10⁻⁷.