NEW YORK (GenomeWeb New) – Oxford Nanopore announced today that it has published a paper demonstrating that it can detect unlabelled DNA bases and methylated cytosine using a protein nanopore covalently attached to an adapter molecule.
The research, which appeared online yesterday in Nature Nanotechnology, validated the feasibility and accuracy of the nanopore sensing component of Oxford Nanopore's sequencing system — illustrating that the nanopore can accurately identify the four standard DNA bases as well as methylated cytosine. As such, the work represents a step toward the company's goal of developing the first label-free, single-molecule DNA sequencing technology.
Each of the DNA bases causes a characteristic current disruption as it moves through the nanopore. That allows continuous sequencing without fluorescent labeling. Oxford Nanopore's BASE technology relies on a protein nanopore coupled to a processive exonuclease enzyme that cleaves DNA bases from the overall DNA strand and places them in the nanopore.
"We have engineered a nanopore with a covalently attached adapter that is capable of continuous nucleoside monophosphate detection without the need for labeling," senior author Hagan Bayley, Oxford Nanopore founder and a researcher at the University of Oxford, and his colleagues concluded. "The nanopore shows accurate discrimination of the four standard dNMPs, reading raw bases with over 99 percent confidence under optimal operating conditions."