Fungal Enzymes and Metabolism in Plastic Degradation: From Polyester Hydrolases to Oxidative Systems

Plastics are persistent pollutants, and their accumulation in terrestrial, aquatic and waste environments is a growing concern. Fungi are promising agents for plastic biodegradation. They secrete a wide range of hydrolytic and oxidative enzymes, colonize hydrophobic surfaces and tolerate harsh conditions. Interest has grown in fungal polyester hydrolases, including cutinases, lipases and esterases, which can act on ester-bonded plastics such as PET, PBAT and PLA. Oxidative systems, including laccases, peroxidases and peroxygenases, are also being explored for plastics with carbon-carbon backbones, such as polyethylene and polystyrene.Despite this progress, key gaps remain. Unlike bacterial systems, the enzymes and genes behind plastic transformation in fungi are often poorly characterized. The regulation of enzyme production and secretion, and its links to fungal physiology and carbon metabolism, is not well understood. Many reports of fungal plastic degradation rely on weight loss, microscopy or spectroscopy alone, which makes it hard to separate true enzymatic depolymerization from surface colonization or abiotic effects. In addition, hydrolytic and oxidative strategies are rarely compared directly.This Research Topic will bring together research on the enzymes, metabolism and physiology that allow fungi to transform plastics. It will consider both hydrolytic and oxidative mechanisms. It also aims to promote rigorous evidence of degradation, including the identification of products, and to connect mechanistic insight with biotechnological and bioremediation applications.The scope covers fungal enzymes and fungal metabolism in plastic transformation, including enzyme discovery, characterization, regulation, engineering and application. Studies of bacterial or mixed microbial systems are welcome when they provide direct comparison with, or insight into, fungal mechanisms. Studies limited to polymer characterization without a microbial or enzymatic component are out of scope.We welcome articles addressing, but not limited to, the following themes:-Discovery and characterization of fungal polyester hydrolases (cutinases, lipases, esterases) and their activity on plastics such as PET, PBAT and PLA-Oxidative enzymes (laccases, peroxidases, peroxygenases and related systems) involved in the transformation of polyolefins and other plastics-Biochemical and structural characterization of plastic-active enzymes, including kinetics, substrate specificity and catalytic mechanisms-Regulation of enzyme expression and secretion, and links to fungal physiology and carbon metabolism-Genomic, transcriptomic, proteomic and secretomic approaches to identify plastic-active enzymes-Identification of degradation products and metabolic fate of plastic-derived compounds in fungal cells-Fungal colonization of plastic surfaces, including the roles of hydrophobins and biofilms-Heterologous production, protein engineering and synthetic biology of fungal plastic-active enzymes-Fungal consortia and fungal–bacterial interactions in plastic degradation-Effects of environmental conditions (temperature, pH, moisture, nutrients) on fungal plastic degradation-Bioremediation and composting applications, from lab to field scale-Methodological advances for demonstrating and quantifying plastic biodegradation Topic editors: Sandra Garrigues, Balasubramanian Velramar, Astrid Mueller Source: https://www.frontiersin.org/research-topics/87221/fungal-enzymes-and-metabolism-in-plastic-degradation-from-polyester-hydrolases-to-oxidative-systems