Having successfully developed nonheme radical azidases and thiocyanases from wt PpMPC, we questioned if our PpMPC variants could also enable the more challenging asymmetric radical isocyanation using NaOCN ( ) as the inexpensive and abundantly available isocyanating reagent. In contrast to biocatalytic azidation and thiocyanation with nonheme Fe enzymes, enantioselective isocyanation remains largely unexploited within the context of new-to-nature nonheme enzymology. The scarcity of nonheme Fe enzymecatalyzed isocyanation via a radical rebound mechanism is likely due to the slower lower radical rebound with Fe(III)-NCO as well as the reduced Fe binding affinity of OCN -. 19b