FIG. 1.

Immunoblot of pyelonephritis isolates with antibodies against P pili. P pilus antibodies were raised against J96 P pili; thus, J96 and UTI89 were used as positive controls for P pilus production. Both isolates are positive for P pili due to a PapA-specific band at a molecular weight of 16,500 (16.5K). However, the P pilus antibody did not recognize the 16.5K protein for the four pyelonephritis isolates, confirming the lack of the pap operon seen with multiplex PCR. Thus, pyelo1, pyelo2, pyelo3, and pyelo4 do not contain the genes, nor do they produce protein associated with P pili, which are thought to be critical in kidney colonization.