Rapid generation of random mutant libraries

A simple and efficient method utilizing in vivo recombination to create recombinant libraries incorporating the products of PCR amplification is described. This will be especially useful for generating large pools of randomly mutagenized clones after error-prone PCR mutagenesis. Here we investigate various parameters to optimize this approach and we demonstrate that as little as 1 pmole of PCR fragment can generate a library with greater than 10⁴ clones in a single transformation without ligation.