Whole-Cell Biotransformation of Benzene to Phenol Catalysed by Intracellular Cytochrome P450BM3 Activated by External Additives

An Escherichia coli whole-cell biocatalyst for the direct hydroxylation of benzene to phenol has been developed. By adding amino acid derivatives as decoy molecules to the culture medium, wild-type cytochrome P450BM3 (P450BM3) expressed in E.coli can be activated and non-native substrates hydroxylated, without supplementing with NADPH. The yield of phenol reached 59% when N-heptyl-L-prolyl-L-phenylalanine (C7-Pro-Phe) was employed as the decoy molecule. It was shown that decoy molecules, especially those lacking fluorination, reached the cytosol of E. coli, thus imparting invivo catalytic activity for the oxyfunctionalisation of non-native substrates to intracellular P450BM3.