4.3.1.30 4Fe-4S-center a radical S-adenosyl-L-methionine-dependent enzyme. Dependence on a [4Fe-4S] cluster and S-adenosyl-L-methionine for DesII activity 715304 4.3.1.30 4Fe-4S-center [4Fe-4S]1+ is the catalytically active form of all radical S-adenosyl-L-methionine-dependent enzymes. Dependence on a [4Fe-4S] cluster and S-adenosyl-L-methionine for DesII activity 715254, 715276 4.3.1.30 additional information in the experiment, the [4Fe-4S]2+ of DesII is reduced to [4Fe-4S]1+ by stepwise electron transfer from NADPH through flavodoxin and flavodoxin reductase. Accordingly, a system consisting of flavodoxin/flavodoxin reductase-NADPH or its equivalent from the cellular pool may serve as the in vivo reducing system for the DesII-catalyzed reaction 715254 4.3.1.30 S-adenosyl-L-methionine a radical S-adenosyl-L-methionine-dependent enzyme. Dependence on a [4Fe-4S] cluster and S-adenosyl-L-methionine for DesII activity 715254, 715304 4.3.1.30 S-adenosyl-L-methionine a radical S-adenosyl-L-methionine-dependent enzyme. Dependence on a [4Fe-4S] cluster and S-adenosyl-L-methionine for DesII activity. Radical S-adenosyl-L-methionine enzymes are an important class of biological catalysts involved in radical mediated transformations in both primary and secondary metabolic pathways. All of these enzymes contain a [4Fe-4S] cluster in the active-site and are S-adenosyl-L-methionine dependent. The reactions are initiated by a single electron transfer from the reduced [4Fe-4S]1+ cluster to SAM to induce the homolytic cleavage of the C5'-S bond in -adenosyl-L-methionine, which yields a reactive 5'-deoxyadenosyl radical along with L-methionine. The 5'-deoxyadenosyl radical is used to generate a substrate radical intermediate that is subsequently converted to product 715276