Single molecule analysis with nanopores
Polymer translocation and sequencing
We have engineered many variants of the α-hemolysin protein pore for single molecule detection (stochastic sensing), which is effected by monitoring the modulation of an ionic current passing through a single pore. Stochastic sensing allows the analysis of a wide variety of analytes: metal cations, small organic molecules, nucleic acids, proteins, and chemicals. The spin-out company from the Bayley laboratory, Oxford Nanopore, has used this technology to sequence single molecules of DNA and RNA.
Following the success of Oxford Nanopore's MinION sequencer, we have redirected our efforts towards protein characterization, in particular the detection of post-translational modifications and alternative splicing. To pass through a nanopore, a protein must unfold so that the polypeptide chain can thread through the narrow lumen. Accordingly, this process is also revealing fundamental information about protein folding and the trafficking of proteins between compartments in cells. We are also investigating oligosaccharide transport and sequencing.
Rosen, C.B., Rodriguez-Larrea, D. and Bayley, H. Single-molecule site-specific detection of protein phosphorylation. Nature Biotechnology 32, 179 (2014). DOI: 10.1038/nnano.2013.22
Kong, L., Almond, A., Bayley, H. and Davis, B.G. Chemical polyglycosylation and nanolitre detection enables single-molecule recapitulation of bacterial sugar export. Nature Chemistry 8, 461 (2016). DOI: 10.1038/NCHEM.2487
Rosen, C.B., Bayley, H. and Rodriguez-Larrea, D. Free-energy landscapes of membrane co-translocational protein unfolding. Communications Biology 13, 160 (2020). DOI: 10.1038/s42003-020-0841-4
Bayley, H. Nanopore sequencing: from imagination to reality. Clinical Chemistry 61, 25 (2015). DOI:10.1373/clinchem.2014.223016