The enzyme, together with EC 1.1.1.396, bacteriochlorophyllide-a dehydrogenase, and EC 4.2.1.165, chlorophyllide a 31-hydratase, is involved in the conversion of chlorophyllide a to bacteriochlorophyllide a. These enzymes can act in multiple orders, resulting in the formation of different intermediates, but the final product of the cumulative action of the three enzymes is always bacteriochlorophyllide a. This enzyme catalyses a trans-reduction of the B-ring; the product has the (7R,8R)-configuration. In addition, the enzyme has a latent activity of EC 1.3.7.13, 3,8-divinyl protochlorophyllide a 8-vinyl-reductase (ferredoxin) [4]. The enzyme contains a [4Fe-4S] cluster, and structurally resembles the Fe protein/MoFe protein complex of nitrogenase (EC 1.18.6.1), which catalyses an ATP-driven reduction.
Cofactor
iron-sulfur
History
Reactions
(1) 3-deacetyl-3-vinylbacteriochlorophyllide a + 2 oxidized ferredoxin [iron-sulfur] cluster + Adp + phosphate = chlorophyllide a + 2 reduced ferredoxin [iron-sulfur] cluster + Atp + H(2)O + 2 H(+). (2) Bacteriochlorophyllide a + 2 oxidized ferredoxin [iron-sulfur] cluster + Adp + phosphate = 3-acetyl-3-devinylchlorophyllide a + 2 reduced ferredoxin [iron-sulfur] cluster + Atp + H(2)O + 2 H(+). (3) 3-deacetyl-3-(1-hydroxyethyl)bacteriochlorophyllide a + 2 oxidized ferredoxin [iron-sulfur] cluster + Adp + phosphate = 3-devinyl-3- (1-hydroxyethyl)chlorophyllide a + 2 reduced ferredoxin [iron-sulfur] cluster + Atp + H(2)O + 2 H(+).
