Fig. 3: Metabolism of linear Ahx oligomers by engineered P. putida strains.
From: Upcycling of polyamides through chemical hydrolysis and engineered Pseudomonas putida
a–c, Strains were grown in MSM with 15 mM Ahx2 (a), Ahx3 (b) or a soluble PA6 fraction containing ε-caprolactam, Ahx and linear Ahx oligomers (c) as sole carbon and nitrogen source. The composition of the soluble PA6 fraction is shown in Extended Data Fig. 9. d, HPLC chromatogram showing the separation of ε-caprolactam (1) and cyclic Ahx oligomers (2–6). Peak numbers correspond to the size (n) of the Ahx oligomers. Compounds were detected with a diode array detector (DAD) at λ = 210 nm. e, HPLC chromatogram of Ahx (1) and linear Ahx oligomers (2–7). Terminal R-NH2 groups were pre-column derivatized using o-phthaldialdehyde (OPA). The derivatives were detected with a fluorescence detector (FLD) with excitation λ = 340 nm and emission λ = 450 nm. f,g, HPLC analysis of culture supernatants of P. putida NYLON-B (f, green) and its ∆PP_0411–4 mutant (g, red) cultivated with the soluble PA6 fraction as sole carbon and nitrogen source. The concentrations of ε-caprolactam and Ahx equivalents (Ahxeq) of Ahx and its linear oligomers are shown for indicated cultivation times. Mean ± s.d. (n = 3).
