Amino acid sequence and antigenicity of the amino-terminus of the 168 kDa adherence protein of Mycoplasma pneumoniae.

The amino-terminal end of the 168 kDa adherence protein from the membrane of Mycoplasma pneumoniae was sequenced up to 12 amino acids. A synthetic peptide containing nine amino acids of this sequence was used to study the antigenicity of the amino-terminus of the 168 kDa protein and the involvement of the homologous sequence of the protein in the adherence process. The synthetic peptide when coupled to ovalbumin was immunogenic in rabbits. Antibodies against this peptide epitope could be demonstrated in sera taken during natural M. pneumoniae infection in humans. The structural domain of the 168 kDa protein homologous with the synthetic peptide did not appear to be involved in adherence, as the synthetic peptide or its homologous antibody failed to inhibit adherence of M. pneumoniae.