Screening of Polyethylene-Degrading Bacteria from Rhyzopertha Dominica and Evaluation of Its Key Enzymes Degrading Polyethylene

Polyethylene (PE) is widely used, and it has caused serious environmental problems due to its difficult degradation. At present, the mechanism of PE degradation by microorganisms is not clear, and the related enzymes of PE degradation need to be further explored. In this study, Acinetobacter baumannii Rd-H2 was obtained from Rhizopertha dominica, which had certain degradation effect on PE plastic. The degradation performance of the strains was evaluated by weight loss rate, SEM, ATR/FTIR, WCA, and GPC. The multi-copper oxidase gene abMco, which may be one of the key genes for PE degradation, was analyzed and successfully expressed in E. coli. The laccase activity of the gene was determined, and the enzyme activity was up to 159.82 U/L. The optimum temperature and pH of the enzyme are 45 degrees C and 4.5 respectively. It shows good stability at 30-45 degrees C. Cu2+ can activate the enzyme. The abMCO was used to degrade polyethylene film, showing a good degradation effect, proving that the enzyme could be the key to degrading PE.

Automated summary

The study demonstrated that Acinetobacter baumannii Rd-H2 from Rhizopertha dominica has a certain degradation effect on polyethylene (PE), and its multi-copper oxidase gene abMco can activate the enzyme, showing good degradation effect on PE film, which may be key to solving the problem of difficult degradation of polyethylene.