Alanine scan of 11 amino acid long novel linear epitope from C. jejuni cj0669 protein

A short sequence of 11 amino acids belonging to the cj0669 protein from Campylobacter jejuni NCTC 11168, which was previously identified as potentially immunogenic, was analyzed via alanine scanning to narrow down the significant amino acid residues within the sequence. Twelve peptides, one representing the original sequence and eleven peptides with each residue replaced by alanine in turn, were synthesized on microarrays by JPTs Pepstar Technology. For each microarray, nine replicates for each peptide were spotted. The microarray was separated into three incubation chambers by the ProPlate 3-well module (Grace Biolabs) to allow for incubation with different antibodies in parallel. For specific interactions, rabbit polyclonal IgG to C. jejuni was used, while unspecific binding to the epitope sequence was checked using rabbit polyclonal IgG to Salmonella enterica.