Fig 3. Specificity of antibodies raised against recombinant proteins AdcA_fm (square grid) and PsaA_fm (vertical stripes).

Sera were used at final dilution of 1:50 and the strain tested was E. faecium E155. Purified recombinant proteins were used as inhibitors at a final concentration of 100μg/mL, 10μg/mL and 1μg/mL. BSA at final concentration of 100μg/mL was used as negative control. The mixtures serum-protein were pre-incubated 1 hour at 4°C prior to OPA. Opsonic killing of the target strain with non-absorbed antibodies was used to assess the reduction of opsonic killing produced by each inhibitor. The corresponding dilutions of antibodies and inhibitor used in the OPA are indicated in the abscissa and the % killing in the ordinate. Bars represent the mean of data and the error bars represent the standard error of the mean.