Processive Incorporation of Deoxynucleoside Triphosphate Analogs by Single-Molecule DNA Polymerase I (Klenow Fragment) Nanocircuits.

ABSTRACT: DNA polymerases exhibit a surprising tolerance for analogs of deoxyribonucleoside triphosphates (dNTPs), despite the enzymes' highly evolved mechanisms for the specific recognition and discrimination of native dNTPs. Here, individual DNA polymerase I Klenow fragment (KF) molecules were tethered to a single-walled carbon nanotube field-effect transistor (SWCNT-FET) to investigate accommodation of dNTP analogs with single-molecule resolution. Each base incorporation accompanied a change in current with its duration defined by τclosed. Under Vmax conditions, the average time of τclosed was similar for all analog and native dNTPs (0.2 to 0.4 ms), indicating no kinetic impact on this step due to analog structure. Accordingly, the average rates of dNTP analog incorporation were largely determine

SUBMITTER: Pugliese KM 

PROVIDER: S-EPMC4925316 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature