Isolation of high molecular weight DNA from soil for cloning into BAC vectors

Isolation of high molecular weight DNA fragments from soil, in excess of 1 Mb, and of sufficient quality for cloning into an Escherichia coli-streptomycete artificial chromosome vector is described. The combination of indirect extraction of cells, using a nycodenz extraction technique, followed by lysis of biomass immobilised in agarose plugs, allowed fragments in excess of 1 Mb to be purified. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.