Tuning a bi-enzymatic cascade reaction in Escherichia coli to facilitate NADPH regeneration for ε-caprolactone production

Abstract ε-Caprolactone is a monomer of poly(ε-caprolactone) which has been widely used in tissue engineering due to its biodegradability and biocompatibility. To meet the massive demand for this monomer, an efficient whole-cell biocatalytic approach was constructed boost ε-caprolactone production using cyclohexanol as substrate. Combining alcohol dehydrogenase (ADH) with cyclohexanone monooxygenase (CHMO) Escherichia coli , self-sufficient NADPH-cofactor regeneration system obtained. Furthermore, some improved variants better substrate tolerance higher catalytic ability were designed by regulating ribosome binding sites. The best mutant strain exhibited yield 0.80 mol/mol 60 mM substrate, while starting only got conversion 0.38 when 20 supplemented. engineered biocatalyst four sequential batches achieve 126 high molar 0.78 mol/mol.