ANALYSIS OF MAJOR SURFACE POLYPEPTIDES OF RICKETTSIA-JAPONICA

Major surface polypeptides of Rickettsia japonica migrated to the posi tion of 120, 135, and 145 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, when the organisms were solubilized at room temp erature. Two major bands at the position of 135 and 185 kDa were seen, when the organisms were solubilized by heating before electrophoresis . Heat-denaturation of the 120- and 145-kDa polypeptides in excised ge l bands changed their mobility and caused them to migrate to 135- and 185-kDa positions, respectively. Two polypeptides at the 120-kDa posit ion were demonstrated: one is a major heat-modifiable polypeptide and the other a minor heat-stable. Peptide mapping was performed to determ ine the identity between native and denatured polypeptides.