Table 2.

Agglutination phenotypes associated with PapG variants and S fimbriae

AdhesinaAgglutination intensityHA inhibition (A1P1RBC)cNeuraminidase sensitivity of HAc
A1P1, OP1, or pig RBCbSheep RBCPk1 RBCP beadsPigeon egg whiteFetuinA1P1 RBCOP1RBCSheep RBC
PapG III+++++++YesNoNoVardNo
PapG II+++++++++++++YesNoNoVarNo
PapG I + III+++++++++++++++YesNoNoVarNo
PapG I+++++++++YesNoNoVarNAe
PapG I′++++++++++++YesNoNoYesNo
S fimbriae++++++++NoYesYesNofYes
  • a Strains used included BOS080, BOS060, and P678-54/pJFK102 (PapG III), IA2 and HB101/pDC1 (PapG II), J96 (PapG I + III), P678-54/pRHU845 (PapG I), L31 (PapG I′), and HU968-298 (S fimbriae).

  • b RBC, erythrocytes. A1P1, OP1, and Pk1 RBC are from human donors.

  • c HA, hemagglutination. Inhibition and sensitivity defined as at least a two-level decrease in agglutination intensity (strongest to weakest, ++++ to −) in the presence of inhibitor or after neuraminidase digestion, respectively.

  • d var., variable between experiments.

  • e NA, not applicable (no HA of sheep RBC).

  • f HA intensity decreased by one intensity level with neuraminidase digestion in both of two trials.