The enzyme, characterized from the bacterium Acetobacterium woodii, contains two [4Fe-4S] clusters and FAD. The enzyme couples the endergonic ferredoxin reduction with NADH as reductant to the exergonic reduction of caffeoyl-CoA with the same reductant. It uses the mechanism of electron bifurcation to overcome the steep energy barrier in ferredoxin reduction. It also reduces 4-coumaroyl-CoA and feruloyl-CoA.
