Single Molecule Spectroscopy of Amino Acids and Peptides by Recognition

When: Thursday, September 26, 2013 at 4:00 pm
Where: DA 114
Speaker: Stuart Lindsay
Organization: Arizona State University
Sponsor: Physics Colloquium

Alternative RNA splicing and post-translational modifications result in millions of tissue and disease dependent protein variants, frequently present in minute concentrations.  There is no “polymerase chain reaction” for amplifying protein, so single molecule protein sequencing is a critical enabling technology in the quest for disease-related biomarkers. Accurately identifying individual amino acid molecules is a significant step towards this goal.  Here we show how Recognition Tunneling (RT) can be used to identify naturally occurring amino acids, including enantiomers, modified amino acids, isobaric isomers and short peptides. The RT electronic “fingerprints” of amino acid molecules can be characterized, and subsequently automatically identified, with a machine-learning algorithm. Thus single molecule, direct electronic protein sequencing may prove possible, either by measuring the products of precessive exo-peptidase digestion, or by using a molecular motor to pull proteins through a tunnel junction incorporating a nanopore.

Host: Assistant Professor Meni Wanunu