Palladium-Mediated Cell-Surface Labeling

Benign C-C bond formation at various sites in cell-surface channels has been achieved through Suzuki-Miyaura coupling of genetically positioned unnatural amino acids containing aryl halide side chains. This enabled site-selective cell surface manipulation of Escherichia coli; the phosphine-free catalyst caused no cell death at required Pd loadings, suggesting future in vivo application of catalytic metal-mediated bond formation in more complex organisms.