Absence of alterations in antigenic determinats inSalmonella typhimurium after mecillinam-induced morphological changes

Abstract

Oval forms ofSalmonella typhimurium resulting from exposure to mecillinam demonstrated electrophoretic differences in the intracellular soluble proteins as compared to the normal organisms. No differences were found, however, in the electrophoretic patterns of cell wall protein.Salmonella rods, or oval forms stained with specific fluorescein-coupled antibodies raised in rabbits against normal or mecillinam-induced abnormal forms, showed identical patterns of fluorescence. Identical lines of precipitins in Ouchterlony system were produced between any combination of antibodies and cytosol protein from normal or mecillinam-exposedSalmonella or with cell wall extracts of either forms. These results indicated that the induced ovoid transformation produced by mecillinam is not accompanied by any demonstrable alterations in the antigenic determinants ofS. typhimurium.