Optimization, reconstruction and heterologous expression of the gene cluster encoding toluene/<i>o</i>-xylene monooxygenase from <i>Pseudomonas stutzeri</i> in <i>Escherichia coli</i> and its successive hydroxylation of toluene and benzene

Biological treatment is a cost-effective and environmentally friendly technique for treating toluene. However, this process limited by the type quantity of toluene degraders that can be applied to different environments methods. It feasible solution constructing new genetic engineering organisms degradation through biotechnology. To facilitate manipulation improve gene expression, toluene/o-xylene monooxygenase locus from Pseudomonas stutzeri was reconstructed artificially synthesized. All six genes were optimized driven with monocistronic transcriptional pattern T7 promoter terminator expressed at high level. The engineered bacteria hydroxylate mixture o-, m- p-cresol, which are then further oxidized 3- 4-methylcatechol. Benzene also phenol, catechol pyrogallol successively. negative effects removed via proteomics analysis. Overall, artificial clusters established in study used construct benzene bioremediation.Supplemental data article available online https://doi.org/10.1080/13102818.2021.1996267 .