DNA interpolyelectrolyte complexes as a tool for efficient cell transformation

Abstract

A tool was developed for enhancement of plasmid penetration into an intact cell, based on increasing DNA hydrophobicity via inclusion into a soluble interpolyelectrolyte complex (IPC) with polycations. The characteristics of formation of DNA IPC with synthetic polycations [poly(N‐ethyl‐4‐vinylpyridinium)bromide (PVP) and PVP modified with 3% of N‐cetyl‐4‐vinylpyridinium units (PVP‐C)] were studied using ultracentrifugation and polyacrylamide gel electrophoresis methods. The conditions were established under which the mixing of DNA and polycation aqueous solutions results in the selfassembly of soluble IPC species. Incorporation of DNA into IPC results in the enhancement of DNA binding with isolated Bacillus subtilis membranes. A considerable increase in the efficiency of transformation of B. subtilis cells with pBC16 plasmid resulted from incorporation of the plasmid into the IPC with PVP and CVP. Copyright © 1991 John Wiley & Sons, Inc.