Western immunoassay of T. denticola parent and mutant strains. Equal amounts of whole-cell extracts of T. denticola 35405 (405) and P0760 were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to membranes, and probed with antibodies raised against recombinant FlaA, PrcA2, PrtP, or Msp polypetides. All samples were heated at 100°C for 5 min prior to electrophoresis, with the exception of Msp-U, which was held at 4°C.