A Review of Microbial Degradation of Plastic: Enzymes and Organisms

Abstract

This review synthesizes research on systematic analysis of microbial applications in degrading plastic and microplastic waste, focusing on bacteria, fungi, actinomycetes, and enzymes such as PETase, cutinase, and laccase to address persistent plastic pollution and remediation challenges. The review aimed to evaluate microbial taxa involved in biodegradation, benchmark enzymatic activities, identify consortia strategies, elucidate metabolic pathways, and assess environmental influences on degradation efficiency. Literature was selected based on comprehensive inclusion of experimental, metagenomic, enzymatic, and biotechnological studies spanning global environmental microbiology and synthetic biology, analyzed through comparative and critical frameworks. Findings reveal diverse microbial communities, including key bacterial and fungal genera, with consortia exhibiting synergistic enzymatic cooperation that enhances polymer breakdown. Enzymatic mechanisms of PETase, cutinase, and laccase demonstrate variable catalytic efficiencies, improved by protein engineering and immobilization, though challenges remain for non-PET plastics. Metabolic pathways for monomer assimilation and gene regulation are partially elucidated, with environmental factors such as temperature and pH critically modulating microbial and enzymatic performance. Integration of multi-omics and synthetic biology advances supports enhanced biodegradation but highlights scalability and methodological standardization gaps. These findings collectively underscore the potential of microbial and enzymatic systems for sustainable plastic waste remediation while emphasizing the need for integrative approaches to optimize efficacy and application in diverse environmental contexts.