Designer Outer Membrane Protein Facilitates Uptake of Decoy Molecules into a Cytochrome P450BM3-Based Whole-Cell Biocatalyst.

Abstract

We report an OmpF loop deletion mutant, which improves the cellular uptake of external additives into an Escherichia coli whole-cell biocatalyst. Through co-expression of the OmpF mutant with wild-type P450BM3 in the presence of decoy molecules, the yield of the whole-cell biotransformation of benzene could be considerably improved. Notably, with C7AM-Pip-Phe the yield duodecupled from 5.7% to 70%, with 80% phenol selectivity. The benzylic hydroxylation of alkyl- and cycloalkylbenzenes was also examined, and with the aid of decoy molecules, propylbenzene and tetralin were converted to 1-hydroxylated products with 78% yield and 94% ( R ) ee for propylbenzene and 92% yield and 94% ( S ) ee for tetralin. Our results suggest that both the decoy molecule and substrate traverse the artificial channel, synergistically boosting whole-cell bioconversions.