DARPins Complex Characterization

One strategy to minimize bacteriophage infections is to competitively block phage adsorption by adding a protein specifically binding to the phage Receptor Binding Proteins (RBPs, BppL trimer). In this application note, we selected three Designed Ankyrin Repeat Proteins (DARPins) and binded to the baseplate of the TP901-1 lactococcal phage. As a part of a structure/function study, we characterized both mass and stoichiometry of each DARPin in complex with either the RBP alone or a multi-protein complex, constituting part of the TP901-1 baseplate and formed by the RBP and the BppU protein.