HAdV-52 short fiber knob binds to sialic acid and long fiber knob binds to CAR.

<p>(A) HAdV-52 long fiber knob (52LFK) and (B) HAdV-52 short fiber knob (52SFK) binding to CHO-cells lacking human CAR (all cells except CHO-CAR), lacking sialic acid (only Lec2) and expressing human CAR (CHO-CAR). (C) 52SFK and 52LFK binding to A549 cells pretreated with <i>V</i>. <i>cholerae</i> neuraminidase. (D) ELISA analysis of 52SFK and 52LFK (in solution) binding to immobilized, sialylated fetuin and asialofetuin type I (chemically prepared) and II (enzymatically prepared). Relative absorbance is shown. (E) Surface plasmon resonance analysis of 52LFK (in solution) binding to CAR (immobilized). A twofold dilution series of 52LFK is shown, ranging from 2 μM to 8 nM. Results are shown as response units (RU). (F) ³⁵S-labeled HAdV-52 virion binding to A549 cells pretreated with <i>V</i>. <i>cholerae</i> neuraminidase (removes α2,3-, α2,6- and α2,8-linked sialic acid) or α2,3-specific neuraminidase at indicated concentrations. All experiments were performed three times with duplicate samples in each experiment. Figure E show one representative set of results. Error bars represent mean ± SD, n.s = not significant, * P of < 0.05, ** P of < 0.01 and *** P of < 0.001 versus control.