Dissolved organic carbon in soils can repress flavonoid bioavailability and disrupt plant nodulation.

Coiled-coil assembly of substrate peptides with dirhodium metallopeptide catalysts enables side-chain modification on the basis of molecular shape. A wide range of amino acids are effectively modified, including the first examples of carboxamide (glutamine and asparagine) modification. The method is used to achieve covalent modification of the c-Fos bZip domain at different residues, depending on the metallopeptide structure. By combining promiscuous catalytic reactivity with specific molecular recognition, this work establishes a general strategy for protein modification on the basis of molecular shape. A broad range of peptide–protein interactions are potentially amenable to this approach.