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The Wittig-type carbonyl olefination reaction has no biocatalytic equivalent. To build complex molecular scaffolds, however, C−C bond-forming reactions are pivotal for biobased economy and synthetic biology. The heme-containing E. coli protein YfeX was found to catalyze carbonyl olefination by reaction of benzaldehyde with ethyl diazoacetate under aerobic conditions in the absence of a triphenylphosphine oxophile. The reaction was performed in whole cells and showed a product formation of 440 mg L−1 in 1 h. It was, moreover, shown that the reaction could be performed under Wittig-analogue conditions in the presence of triphenylphosphine or triphenylarsine. [ABSTRACT FROM AUTHOR]

The Cover shows an enzymatic carbonyl olefination reaction in E.coli where the corresponding enzyme—depicted as the clownfish nemo—has to be found in the organism which is represented by the ocean. In their paper, Weissenborn, Löw et al. present a method to find new enzyme activities by utilizing an entire cell lysate with its thousands of proteins as catalyst. Once they found that the cell lysate catalyzes a carbonyl olefination reaction they determined, isolated, and studied the corresponding protein. The results show the first enzymatic carbonyl olefination in absence of phosphines, as well as the feasibility of the performed general approach in cell lysates. More information can be found in the Communication by Weissenborn, Löw et al. on page 1636 in Issue 9, 2016 (DOI: 10.1002/cctc.201600227). [ABSTRACT FROM AUTHOR]