DNA fingerprinting of Arsenite Resistant Bacterial Isolates: PCR based

The disposal of toxic heavy metals such as arsenic posed high risk to the environment. Arsenite [As(III)], a reduced form of arsenic, is more toxic and mobile than arsenate [As(V)]. The aim of this work was to isolate arsenic-tolerant bacteria from contaminated soil collected from various industrial landfills of Gujarat, India. This study explores the potential of the amplified ribosomal DNA restriction analysis (ARDRA) for intra and interspecies identification of the Bacillus sp. A set of primers was used to amplify part of the 16S rDNA as well as the 16S spacer from isolates belonging to different bacillus species. Restriction analysis was carried out with nine different restriction enzymes, namely Alu I, Hae III, Hpa II, Sau 3AI , Taq I, RsaI, Cac8I, Bst NI and Bsa JI. Homologous sequence obtained by standard nucleotide- nucleotide BLAST (BLASTn) were aligned with the isolate sequence using CLUSTAL program. The phylogenetic tree showed that the isolates falls under evolutionary clustal comprising members of bacillus group. This PCR-RFLP method provides a rapid tool for the identification of arsenite resistant bacterial isolates and the detection of new taxa.