Exploring the Polyethylene Degradation Efficiency of Bacillus vallismortis SK070

Abstract

In the rapid growing world, plastic consumption increased on a large scale, intensifying environmental pollution. As conventional waste management approaches prove inadequate, microbial degradation emerges as a promising and innovative solution. This study investigates the microbial communities in soil contaminated with plastic waste from a dump yard in Jawahar Nagar, Hyderabad, Telangana. A composite soil sample, SKP007, was analysed using 16S V3-V4 region metagenomic sequencing on the Illumina MiSeq platform. Phylum-level analysis revealed predominant groups including Proteobacteria, Chloroflexi, Actinobacteria, Acidobacteria and Firmicutes, with Bacillus, Rubrobacter, Streptomyces, and Steroidobacter as dominant genera. Following a 14-day enrichment period, six bacterial isolates were screened for plastic degradation. Isolate SK070 exhibited the highest plastic degradation efficiency, with a clearance zone diameter of 4.2 ± 0.3 mm and a degradation rate of 3.95 ± 0.06%. Morphological characterization of SK070 revealed rod-shaped bacteria with blunt ends. Molecular analysis through 16S rRNA sequencing identified SK070 as Bacillus vallismortis, showing 99.99% similarity. Phylogenetic analysis confirmed its close relationship with Bacillus subtilis. This study highlights Bacillus vallismortis SK070 as a promising candidate for plastic bioremediation, warranting further investigation into its optimization and genomic features.