Moleculer Surgery of DNA Using Enzyme-Immobilized Particles

Abstract

This paper proposes, and experimentally demonstrates, a novel method of 'molecular surgery' of DNA, where a enzyme-labeled particle or probe is pressed against DNA, which is immobilized on the substrate with known conformation and orientation, to make chemical modifications at arbitrary positions of the DNA molecule. In the method presented in this paper, DNA is subjected to high-intensity high-frequency electric field (≥1MV/m, ≈1MHz) created in micro-fabricated electrodes, so that it is 1) stretched to a straight conformation parallel to the field by the electrostatic orientation effect, and 2) positioned onto a substrate by the dielectrophoresis. Once DNA is thus stretch-and-positioned, one has access to arbitrary position of any one of aligned molecules. A latex particle, 2.8μm in diameter, is labeled with DNA-cutting enzyme, DNaseII, and is laser-manipulated and contacted with DNA. It is observed that DNA is instantaneously cut at the contact point. This result is considered to be the first demonstration of space-resolved biochemical modification.