Functional Display of a Heterologous Protein on the Surface of Lactococcus lactis by Means of the Cell Wall Anchor of Staphylococcus aureus Protein A

Abstract

ABSTRACT In this study, we showed that the cell wall anchor of protein A from Staphylococcus aureus is functional in the food-grade organism Lactococcus lactis . A fusion protein composed of the lactococcal Usp45 secretion signal peptide, streptavidin monomer, and the S. aureus protein A anchor became covalently attached to the peptidoglycan when expressed in L. lactis . The streptavidin moiety of the fusion protein was functionally exposed at the cellular surface. L. lactis cells expressing the anchored fusion polypeptide could be specifically immobilized on a biotinylated alkaline phosphatase-coated polystyrene support.