*5.3.3 Restriction fragment length polymorphism (RFLP)/amplified ribosomal DNA restriction analysis (ARDRA)*

It is another tool used to study microbial diversity that relies on DNA polymorphisms. PCR amplified rDNA is digested with a 4-base pair cutting restriction enzyme. Different fragment lengths are detected using agarose or non-denaturing polyacrylamide gel electrophoresis in the case of community analysis. RFLP fingerprint can be used to measure bacterial community structure. ARDRA is a DNA fingerprinting technique based on PCR amplification of 16S ribosomal DNA using primers for conserved regions, followed by restriction enzyme digestions and agarose gel electrophoresis. ARDRA was used successfully to study and compare the microbial diversity in copper contaminated soils [31]. Sklarz and his associates evaluated the use of amplified rDNA restriction analysis assay for identification of bacterial communities and concluded that ARDRA based dendrograms may not mirror 16S rDNA sequence based phylogenetic trees [32].
