Author
BASSET, GILLES - University Of Florida | |
LATIMER, SCOTT - University Of Florida | |
FATIHI, ABDELHAK - Institut Jean-Pierre Bourgin (IJPB) | |
SOUBEYRAND, ERIC - University Of Florida | |
Block, Anna |
Submitted to: Mini-Reviews in Medicinal Chemistry
Publication Type: Review Article Publication Acceptance Date: 6/21/2016 Publication Date: 7/11/2017 Citation: Basset, G.J., Latimer, S., Fatihi, A., Soubeyrand, E., Block, A.K. 2017. Phylloquinone (vitamin K1): occurrence, biosynthesis and functions. Mini-Reviews in Medicinal Chemistry. 17(12):1028-1038. Interpretive Summary: Technical Abstract: Phylloquinone is a prenylated naphthoquinone that is synthesized exclusively by plants, green algae, and some species of cyanobacteria, where it serves as a vital electron carrier in photosystem I and as an electron acceptor for the formation of protein disulfide bonds. In humans and other vertebrates, phylloquinone plays the role of a vitamin (vitamin K1) that is required for blood coagulation and bone and vascular metabolism. Phylloquinone from green leafy vegetables and vegetable oil represents the major dietary source of vitamin K for humans. In recent years, reverse genetics and biochemical approaches using the model plant Arabidopsis thaliana have shown that phylloquinone biosynthesis in plants involves paralogous and multifunctional enzymes, a compartmentation of the corresponding pathway in plastids and peroxisomes, and trafficking of some biosynthetic intermediates within plastids themselves. Furthermore, phylloquinone biosynthetic intermediates create crucial metabolic branch-points with other plastid-synthesized metabolites such as chlorophylls, tocopherols and salicylate. This review presents an update on recent studies of the central role of plastids in the biosynthesis of phylloquinone, in particular on the discovery of novel enzymatic steps that are likely paradigms for phylloquinone and menaquinone (vitamin K2)-synthesizing organisms alike. |