Fig. 4: Experimental characterization of the highly active variant Bhr-NMT under industrial conditions.

a Comparison of PET depolymerization by Bhr-NMT and LCC-ICCG over a temperature range of 50 °C–80 °C. Reactions were conducted in triplicate, using 0.16% (w/w) amorphized Pc-PET powder and 1 mg_enzyme g_PET⁻¹ in 100 mM phosphate buffer (pH 8.0) for 8 h. b Time-course analysis of PET depolymerization by Bhr-NMT and LCC-ICCG at 68 °C over 12 h. Reactions were conducted in triplicate, using 0.16% (w/w) of amorphized Pc-PET powder and 1 mg_enzyme g_PET⁻¹ in 100 mM phosphate buffer (pH 8.0). Unpaired, one-tailed t-tests were implemented to statistically assess differences in enzymatic product yields between different PET hydrolases (“*”: P < 0.05, “**”: P < 0.01, “***”: P < 0.001, “ns”: the group not statistically significant (P ≥ 0.05); exact P values are provided in the Supplementary Data File 1). The error bars represent the standard deviation of all products for each enzyme. c, d Comparison of PET depolymerization by Bhr-NMT and LCC-ICCG under high PET substrate concentrations in a bioreactor. The reaction system had a total volume of 50 ml, containing 16.5% (w/v) amorphized Pc-PET powder and 0.5 mg_enzyme g_PET⁻¹ (or 0.3 mg_enzyme g_PET⁻¹) in 100 mM phosphate buffer at pH 8.0. The circles represent the conversion measured by the consumption of NaOH, while the crosses indicate the conversion calculated by HPLC analyses. The detailed data were provided in Table S10.