Fig. 4

Proposed pathway for PET, BHET and terephthalic acid (TPA) degradation by Thioclava sp. BHET1 and Bacillus sp. BHET2 informed by proteomic and metabolomic analyses. The metabolomics data obtained from I. sakaiensis and community culture analyses were also included. Initial substrates are shown in black boxes with white text along with the chemical structures for all substrates and proposed intermediates. Pathways involving multiple steps are indicated in grey boxes. Substrates detected by metabolomics within each treatment (blue to green colour scale; treatments PET, BHET and terephthalic acid as indicated on the left of the box) are represented by their fold change between each bacterial strain (i.e. Thioclava sp. BHET1, ‘Thio’; Bacillus sp. BHET2, ‘Baci’, Ideonella sakaiensis, ‘Ideo’ and in community incubations, ‘Comm’) and negative controls (substrate incubated with no microbial inoculum). Bold values indicate changes that were significant (two independent samples T test; p < 0.05). Enzymes proposed to catalyse each step, and that were detected by high-throughput proteomics, are indicated with the fold change between each condition (PET, BHET and terephthalic acid) and the labile control (i.e. growth with fructose). Only enzymes from Thioclava sp. BHET1 are shown as the pathway used by Bacillus sp. BHET2 could not be determined. Proteomic analysis of I. sakaiensis was not performed