The urgent need to develop revolutionary technologies, for sequencing large DNA molecules quickly and economically, has led to many experimental strategies. Chief among these are the nanopore-based electrophoretic experiments. In these experiments, translocation of single molecules of DNA is monitored as they pass through protein channels and solid-state nanopores under an external electric field. While the results from such experiments are extremely promising towards reaching $1000 genome target, there are many puzzles and the physics of these nanoscopic systems needs to be understood from a fundamental scientific point of view. The proposed research deals with a fundamental understanding of the behavior of DNA in nanopore environments under the influence of electrical and hydrodynamic forces. We will investigate the challenges underlying several key system components in the goal of reducing the cost of sequencing mammalian-sized genomes to $1000. The major challenges deal with the predictability of capture of the target molecule at the nanopore, efficient threading into the pore, and slowing down the translocating molecule through the pore. We will use a combination of statistical mechanics theory, computer simulations, and numerical computation of coupled nonlinear equations to address polymer statistics and dynamics, electrostatics, and hydrodynamics in the phenomena of DNA translocation. The proposed research, while being generally relevant to all nanopore-based experiments, will be hinged specifically on: (a) role of hybridization in translocation through a-hemolysin, MspA, and solid-state pores, (b) enzyme-modulated DNA translocation through channels, and (c) control of capture rate and successful translocation rate of DNA in protein channels and solid-state nanopores.
Availability of low-cost technologies for DNA sequencing is vital in identifying the origins of diseases and maintenance of public health. The proposed research addresses the challenges in several key system components in the development of genome sequencing technologies at the cost of $1000 per a mammalian-sized genome.
Showing the most recent 10 out of 57 publications