Figure 1.

Comparison of cloned plasmids produced from an equimolar mixture of three DNA fragments of different sizes by RC and LC. Plasmids retrieved from transformants generated by RC and LC were digested with BglII (A) or BsrGI (B), and then run on 0.7 or 1.2% agarose gels, respectively. Plasmids were linearized by BglII digestion, and inserts were excised from the vector (pSP73) by BsrGI digestion. Because the resultant clones by RC contained recombination site sequences in the vector portion, the size of the RC plasmid became slightly larger than that of the LC plasmid even when it carried the same insert. In (B), contaminating E.coli chromosomal DNA appeared as the uppermost band in both lanes and the excised βGal fragment, which should run slightly slower than the vectors, was not seen in either lane.