Peptides and antibodies can be used as new handles and anchors for single-molecule cut and paste (SMC&P), as reported by Hermann Gaub and co-workers, University of Munich, Germany. According to the authors, their most recent results are an important step towards the assembly of all-protein molecular devices.

SMC&P can be applied to select individual molecular building blocks, such as enzymes, and place them at a chosen position on a construction site. It combines the Ångstrom positioning precision of the atomic force microscope (AFM) with the selectivity of molecular recognition.

Up to now, researchers had only used DNA oligomers as general molecular handles and anchors. But to make SMC&P widely applicable, an all-protein approach is required. Gaub and colleagues have employed a novel handle system based on a short peptide on the molecular building blocks, which is recognized by a specific antibody at the AFM tip. “We could unambiguously demonstrate that molecular arrangements can be assembled one by one with a precision much better than the resolution limit of the light microscope”, the authors say.

_{Image: © Wiley-VCH}

• Peptide–Antibody Complex as Handle for Single-Molecule Cut & Paste,
  M. Strackharn, S. W. Stahl, P. M. D. Severin, T. Nicolaus, H. E. Gaub,
  ChemPhysChem 2012, 13.
  DOI: 10.1002/cphc.201100765