Peptide M is a 50 aa synthetic peptide derived from a streptococcal M protein containing an additional C-terminal cysteine residue.
Peptide M binds monomeric and dimeric human IgA of both subclasses (IgA1 and IgA2) with high specificity and affinity.
It also binds bovine IgA but not murine IgA. Peptide M binding occurs at a site in IgA-Fc conserved in human IgA1 and IgA2 and bovine IgA but not in mouse IgA.
Peptide M can be used for single-step affinity purification of IgA and for specific detection of antigen-bound IgA.
- Sandin C. et al., 2002. Isolation and detection of human IgA using a streptococcal IgA binding peptide. J Immunol. 169(3):1357-64.