Functional and Selective Bacterial Interfaces Using Cross-Scaffold Gold Binding Peptides

Abstract

We investigated the functional and selective activity of three phage-derived gold-binding peptides on the Escherichia coli (E. coli) bacterial cell surface display scaffold (eCPX) for the first time. Gold-binding peptides, p3-Au12 (LKAHLPPSRLPS), p8#9 (VSGSSPDS), and Midas-2 (TGTSVLIATPYV), were compared side-by-side through experiment and simulation. All exhibited strong binding to an evaporated gold film, with approximately a 4-log difference in binding between each peptide and the control sample. The increased affinity for gold was also confirmed by direct visualization of samples using Scanning Electron Microscopy (SEM). Peptide dynamics in solution were performed to analyze innate structure, and all three were found to have a high degree of flexibility. Preferential binding to gold over silicon for all three peptides was demonstrated, with up to four orders of magnitude selectivity exhibited by p3-Au12. The selectivity was also clearly evident through SEM analysis of the boundary between the gold film and silicon substrate. Functional activity of bound E. coli cells was further demonstrated by stimulating filamentation and all three peptides were characterized as prolific relative to control samples. This work shows great promise towards functional and active bacterial-hybrid gold surfaces and the potential to enable the next generation living material interfaces.

Influences of Adhesion Variability on the “Living” Dynamics of Filamentous Bacteria in Microfluidic Channels

“…Filamentous E. coli on uroepithelial cells in vivo have been previously reported to reach 80 μm in length and, presumably, use mannose contacts for strong adhesion [5,24]. Aztreonam-induced filaments, however, have only been reported to reach a maximum of 43 μm in length before lysing, except when surface-bound [29,67]. Thus, the glycoprotein-laden adhesive surface provided to filamenting E. coli in this work may offer a tissue-like substrate to facilitate filamenting behavior that is closely representative of natural mechanisms of E. coli persistence.…”

The next generation of biopanning: next gen sequencing improves analysis of bacterial display libraries

“…Assessing populations for binding enrichment on nonantigenic material surfaces using bacterial display libraries in the absence of fluorescence has depended on methods that require additional steps, such as SEM sputter coating for nonconductive surfaces or indirect binding assays [6,22]. Indirect binding assays require an additional growth step after material incubation to amplify individual binders, followed by serial dilution and replicated plating of library populations.…”

Study on Interfacial Science and Rheology

“…Adams, Harley & Jahnke [1] showed gold surface selective peptide interface is used for the selforganization of the cell. Also, the continuous cell elongation without division is future research for living material interfaces.…”