Structural basis of terephthalate recognition by solute binding protein TphC

• Published in: Nature communications Vol. 12; no. 1; p. 6244
• Main Authors: Gautom, Trishnamoni, Dheeman, Dharmendra, Levy, Colin, Butterfield, Thomas, Alvarez Gonzalez, Guadalupe, Le Roy, Philip, Caiger, Lewis, Fisher, Karl, Johannissen, Linus, Dixon, Neil
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 29.10.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 631/92/577; 639/638/45/56; 82/80; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Bacterial Proteins - isolation & purification; Bacterial Proteins - metabolism; Biodegradation; Bioremediation; Calorimetry; Comamonas - chemistry; Comamonas - genetics; Comamonas - metabolism; Crystallography, X-Ray; Ethylene glycol; Fluorometry - methods; Genomic analysis; Homology; Humanities and Social Sciences; Ligands; Metabolic engineering; Metabolism; Models, Molecular; Molecular Docking Simulation; Monomers; multidisciplinary; Mutation; Operon; Operons; Phthalic Acids - metabolism; Phylogeny; Plastics; Polyethylene; Polyethylene terephthalate; Protein Conformation; Proteins; Science; Science (multidisciplinary); Structural analysis; Xenobiotics - metabolism
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-26508-0

Biological degradation of Polyethylene terephthalate (PET) plastic and assimilation of the corresponding monomers ethylene glycol and terephthalate (TPA) into central metabolism offers an attractive route for bio-based molecular recycling and bioremediation applications. A key step is the cellular uptake of the non-permeable TPA into bacterial cells which has been shown to be dependent upon the presence of the key tphC gene. However, little is known from a biochemical and structural perspective about the encoded solute binding protein, TphC. Here, we report the biochemical and structural characterisation of TphC in both open and TPA-bound closed conformations. This analysis demonstrates the narrow ligand specificity of TphC towards aromatic para-substituted dicarboxylates, such as TPA and closely related analogues. Further phylogenetic and genomic context analysis of the tph genes reveals homologous operons as a genetic resource for future biotechnological and metabolic engineering efforts towards circular plastic bio-economy solutions. The presence of the gene encoding the solute binding protein TphC has been shown to permit the uptake of terephthalate (TPA), which is the breakdown product of Polyethylene terephthalate (PET) plastic. Here the authors present a structural characterization of TphC in both open and TPA-bound closed conformations.