In silico approach for evaluating the degradation efficiency of plastic degrading enzyme mono(2-hydroxyethyl) terephthalic acid hydrolase (MHETase) of selected bacteria

Abstract

Plastics, which are complex polymers, have been a persistent problem due to their inherent non-biodegradability, despite their numerous applications. The huge piles of accumulated plastic are not only damaging to the environment, but also a major contributing factor to deteriorating human health. Over the years, plastic waste has been recycled and treated using conventional and advanced non-biodegradable waste treatment technologies such as incineration and landfilling, and pyrolysis and thermodegradation. However, these face their own set of challenges, and hence the use of microbial enzyme machineries to degrade plastic has recently garnered attention. We attempted to find the species that degrades mono(2-hydroxyethyl) terephthalic acid (MHET) with the highest efficiency in this study by using in silico screening of the enzyme mono(2-hydroxyethyl) terephthalic acid hydrolase (MHETase). Using the MHETase enzyme sequence of Ideonella sakaiensis as the query sequence, BLAST analysis was performed to identify the top 10 homologous sequences in other species. To identify the degrading efficiency, molecular docking using PatchDock between MHETase of different species with MHET as ligand was performed. The species Pigmentiphaga litoralis had the highest docking score of 3634, and this shows that this species degrades MHET most efficiently. The interaction studies showed that this docked molecule has 7 hydrophobic interactions and 1 hydrogen bonds. In the recent years, use of bioinformatics tools is unprecedented, growing fast and it became one of the important component in any biological research activity.