A new catalytic mechanism of bacterial ferredoxin-NADP reductases due to a particular NADP binding mode.

Ferredoxin-NADP reductases (FNRs) are ubiquitous flavoenzymes involved in redox metabolisms. FNRs catalyze the reversible electron transfer between NADP(H) and ferredoxin or flavodoxin. They are classified as plant- and mitochondrial-type FNR.

A bacterial 2[4Fe4S] ferredoxin as redox partner of the plastidic-type ferredoxin-NADP reductase from Leptospira interrogans.

Background: Ferredoxins are small iron-sulfur proteins that participate as electron donors in various metabolic pathways. They are recognized substrates of ferredoxin-NADP reductases (FNR) in redox metabolisms in mitochondria, plastids, and bacteria. We previously found a plastidic-type FNR in Leptospira interrogans (LepFNR), a parasitic bacterium of animals and humans.