Binding of phage-display-selected peptides to the periplasmic chaperone protein SurA mimics binding of unfolded outer membrane proteins.
SurA is a periplasmic chaperone protein that facilitates maturation of integral outer membrane proteins (OMPs). Short peptides that bind SurA have previously been characterized. In this work, an enzyme-linked immunoabsorbent assay-based competition assay is utilized to demonstrate that binding of such peptides, presented by peptide-tagged phage, mimics binding of biological substrates. Two representative unfolded OMPs, OmpF and OmpG, bind SurA and a core structural fragment thereof in competition with peptide-tagged phage, and with the same order-of-magnitude affinity as the peptides. Additionally, unfolded OmpF and OmpG bind SurA more tightly than an unfolded water-soluble protein, while folded proteins have no measurable affinity, demonstrating a specificity of SurA for OMP polypeptides.
Bitto
Eduard
E
Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
McKay
David B
DB
D001435:Bacteriophages / Q000235:genetics*; D002352:Carrier Proteins / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D010455:Peptides / Q000235:genetics / Q000378:metabolism*; D019696:Peptidylprolyl Isomerase / Q000378:metabolism*; D011485:Protein Binding; D011994:Recombinant Proteins / Q000378:metabolism
D002352:Carrier Proteins; D010455:Peptides; D011994:Recombinant Proteins; C098640:periplasmic peptidylprolyl cis-trans isomerase; D019696:Peptidylprolyl Isomerase