Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2052101 | FEBS Letters | 2006 | 4 Pages |
Dark-operative protochlorophyllide reductase (DPOR) in bacteriochlorophyll biosynthesis is a nitrogenase-like enzyme consisting of L-protein (BchL-dimer) as a reductase component and NB-protein (BchN–BchB-heterotetramer) as a catalytic component. Metallocenters of DPOR have not been identified. Here we report that L-protein has an oxygen-sensitive [4Fe–4S] cluster similar to nitrogenase Fe protein. Purified L-protein from Rhodobacter capsulatus showed absorption spectra and an electron paramagnetic resonance signal indicative of a [4Fe–4S] cluster. The activity quickly disappeared upon exposure to air with a half-life of 20 s. These results suggest that the electron transfer mechanism is conserved in nitrogenase Fe protein and DPOR L-protein.