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Hydroquinone (HQ) is produced commercially from benzene by multi‐step Hock‐type processes with equivalent amounts of acetone as side‐product. We describe an efficient biocatalytic alternative using the cytochrome P450‐BM3 monooxygenase. Since the wildtype enzyme does not accept benzene, a semi‐rational protein engineering strategy was developed. Highly active mutants were obtained which transform benzene in a one‐pot sequence first into phenol and then regioselectively into HQ without any overoxidation. A computational study shows that the chemoselective oxidation of phenol by the P450‐BM3 variant A82F/A328F leads to the regioselective formation of an epoxide intermediate at the C3=C4 double bond, which departs from the binding pocket and then undergoes fragmentation in aqueous medium with exclusive formation of HQ. As a practical application, an E. coli designer cell system was constructed, which enables the cascade transformation of benzene into the natural product arbutin, which has anti‐inflammatory and anti‐bacterial activities. Unique enzymatic one‐pot dihydroxylation of benzene to hydroquinone: A mutant of a cytochrome P450 monooxygenase catalyzes this challenging transformation with no overoxidation, enabling, among other things, the cascade synthesis of biologically active arbutin. [ABSTRACT FROM AUTHOR]

Although the circulation of avian influenza viruses in humans is limited, they can be transmitted from Aves (birds) to humans, representing a great challenge. Herein, we suggest that influenza viruses from Aves might exist in a mineralized state owing to the high calcium concentrations in the avian intestine. Using two typical influenza viruses as examples, we demonstrate that these viruses can self-mineralize in simulated avian intestinal fluid, resulting in egg-like virus-mineral structured composites. The mineralized viruses are more robust, with enhanced infectivity and thermostability. More importantly, the mineral exterior of mineralized viruses can alter their cell internalization, expanding the possible tropisms. The discovery of a mineralized state of influenza viruses highlights the integration of nanomaterials and viruses in the environment, which provides a new understanding of avian influenza infection and its control. [ABSTRACT FROM AUTHOR]

The unique enzymatic one‐pot dihydroxylation of benzene to hydroquinone can be achieved as described by A. Li, M. T. Reetz et al. in their Communication on page 764 ff. A mutant of a cytochrome P450 monooxygenase obtained by a semirational protein engineering strategy catalyzes this challenging transformation with no overoxidation, enabling, among other things, the cascade synthesis of biologically active arbutin by a constructed Escherichia coli designer cell system. [ABSTRACT FROM AUTHOR]