| Abstract [eng] |
Due to insufficient plastic waste management, plastic pollution has become one of the greatest challenges of the 21st century. Microplastics and nanoplastics formed from larger plastic parts are even more problematic due to the resistance to natural degradation, increased surface area and ubiq-uity. Their detrimental effects on aquatic and terrestrial ecosystems as well as human health have been proven. Due to the variability of microbial metabolism, microorganisms have begun to modify their metabolism to degrade plastic to use it as a carbon source. Large scale application of these en-zymes could be a sustainable solution to mitigate global plastic pollution due to environmental friendliness. However, sufficient fundamental knowledge has not yet been accumulated. The aim of this study is to explore different both natural and artificial sources for microorgan-ismal genes that encode enzymes that are associated with degrading various types of (micro)plastics. For that, metagenomic DNA was isolated from 47 environmental samples and subjected to PCR analysis. Samples from water bodies showed a low amplification rate, thus were excluded from further testing. After PCR analysis of 34 samples for the genes that encode alkane hydroxylas-es, styrene monooxygenases, PET-active cutinases, urethanase and PUR-active lipase, 134 ampli-cons were subjected to sequencing. Sequencing revealed that the microbiome of the waste treatment plant is capable of depoly-merising PET and PUR, degrading of urethane and styrene, as well as degrading of pretreated PE. The microbiota from the closed landfill harbors genes for enzymes active on PET, pretreated PE, and styrene. A potential for the degradation of pretreated PE was identified in samples from the active landfill. Surprisingly, samples of soil collected from the garden showed potential for the deg-radation of pretreated PE and styrene, as well as for surface modification of PET. These results prove that prolonged contact of microbiome with contaminants may increase the prevalence and diversity of genes associated with plastic biodegradation but also suggest that it may be reasonable to broaden the focus of search to different environments to find new enzymes. |
