Reacquisition of specific proteins confers virulence in Mycoplasma pneumoniae

Hemadsorbing revertants were isolated from spontaneous hemadsorption-negative, avirulent mutants of Mycoplasma pneumoniae. The revertants simultaneously reacquired specific proteins absent in their homologous mutants, along with neuraminidase-sensitive adherence to the respiratory epithelium and virulence. Peptide mapping and immunological analysis indicated no precursor-product relationships among certain of these proteins.