A two primers random amplified polymorphic DNA procedure to obtain polymerase chain reaction fingerprints of bacterial species

Polymerase chain reation (PCR) fingerprints are used to characterize and re cognize bacteria and are generally obtained using universal primers that ge nerate an array of DNA amplicons, which can be separated by electrophoresis . Universal primers 8F and 1491R have been used to amplify specifically 16S rDNA. We have used these primers at an annealing temperature of 50 degrees C. Agarose gel electrophoresis of PCR products revealed several bands. The band pattern of each bacterial species was different and the strains belong ing to the same species shared an identical pattern. The patterns obtained did not show variations with plasmid DNA content or the growth stage of the bacteria. The peculiarity of the randomly amplified polymorphic DNA (RAPD) described in this work lies in the use of two large primers (proximately 2 0 nt) to obtain the pattern, since normally a only smaller primer is used, and in the new application for the primers used to amplify 16S rDNA. This n ew procedure, called two primers (TP)-RAPD fingerprinting, is thus rapid, s ensitive, reliable, highly reproducible and suitable for experiments with a large number of microorganisms, and can be applied to bacterial taxonomy, ecological studies and for the detection of new bacterial species.