FIG 3.
PspA binds to LDH-A via NPB. (A) Interaction of PspA with LDH-A or LDH-B was analyzed by ELISA under different PspAWU2 concentrations. (B) Diagram of PspAWU2 fragments (F-1 to F-5) used in the pulldown experiments, the corresponding truncated mutants created for testing of PspA binding to LDH-A and PRDs (see Fig. S3A in the supplemental material). (C) Different versions of PRD from designated Spn strains were tested for their ability to bind LDH-A in pulldown experiments (Fig. S3B). (D) Spn WU2, its isogenic pspA deletion mutant (WU2ΔpspA), and a isogenic NPB deletion mutant of PspA (WU2ΔNPB) were incubated with FITC-conjugated rabbit LDH-A. The LDH-A binding to pneumococci was measured by flow cytometry. Data are geometric means (means and standard errors shown) of the log fluorescence intensity measured on a flow cytometer (n = 3).