FIG 2.

Effect of flow on mode of adhesion. (A) The results of the experiments described for Fig. 1 were further analyzed to classify movements of bound bacteria. The positions of individual GspB+ bacteria binding to ecGPIbα at 1.4 dyn/cm² are shown over a 25-s period to illustrate how bacteria switch between stationary and rolling modes of adhesion. The “X” indicates where a bacterium detached. Each track is assigned a number to facilitate the description of these data in the text. (B to D) The fraction of stationary bacteria (defined as bacteria that do not move within 1 s) is shown for the indicated streptococcal strains binding to surfaces coated with platelets (B), ecGPIbα (C), and sTa (D) at the indicated levels of fluidic shear stress. Each data point shows the average and standard deviation of data taken on two (B) or three (C and D) days.