Rapid procedure for isolation and detection of Salmonella plasmids

A rapid procedure is described for the isolation of high quality and quanti ty plasmid DNA from Salmonella. Plasmids of molecular mass ranging from 10 kbp to 147 kbp were isolated. The method yielded enough DNA from the low co py number virulence plasmids of various Salmonella serovars for visualizati on on an agarose gel. The method is based on the classic alkaline lysis met hods, employing the same reagents, but without any incubation steps. Isolat ion of plasmid DNA was also attempted with the use of rapid DNA isolation k its, but without success. It was reasoned that endonucleases, present in th e resin, might have degraded the plasmids.