Molecular Identification and Phylogenetic Characterization of Heavy Metal Removing Bacteria Isolated from E-Waste Affected Soils
Keywords:
E-waste, 16S rRNA gene, Molecular identification, Phylogenetic analysis, Heavy metal resistance, BioremediationAbstract
The rapid accumulation of electronic waste (e-waste) has emerged as a major environmental concern due to the release of toxic heavy metals into surrounding soil ecosystems. This study aimed to perform molecular identification and phylogenetic characterization of heavy metal removing bacteria isolated from e-waste affected soils. Bacterial isolates exhibiting strong multi-metal resistance were subjected to genomic DNA extraction followed by PCR amplification of the 16S rRNA gene. The amplified products were sequenced and analyzed using BLAST to determine taxonomic affiliation, and phylogenetic relationships were inferred using standard tree-building methods. Molecular analysis revealed that the isolates belonged to diverse bacterial genera known for environmental adaptability and metal resistance. Phylogenetic clustering showed close evolutionary relationships with established metal-tolerant reference strains, indicating genetic adaptation to prolonged heavy metal stress. The findings provide molecular-level confirmation of the identity and evolutionary relationships of indigenous bacteria and support their potential application in sustainable bioremediation strategies for heavy metal contaminated environments associated with improper e-waste disposal.
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