[Pyoverdin from Pseudomonas fluorescens: binding to the globulin fraction of serum and its effect on serological reaction titers].

Pseudomonas fluorescens grows and produces pigment in refrigerated human blood at 4 degrees C. Saline precipitation of plasma showed that globulin and albumin fractions retained pyoverdin at different concentrations. By dialysis it was possible to determine that the pigment attached or aggregated to the protein in total plasma as well as in the fraction obtained by saline precipitation. A greater binding was observed at the globulin fraction. Gamma-globulin immunological activity was reduced due to the interaction with pyoverdin, as much in agglutination reaction (VDRL) as in neutralization (Streptolysin O).