Phylloquinone biosynthetic pathway

Semenov, A.Y., VassiHev, I.R., van der Est, A., Mamedov, M.D., Zybailov, B., Shen, G., Stehhk, D., Diner, B.A., Chitnis, P.R., and Golbeck, J.H., Recruitment of a foreign quinone into the Aj site of Photosystem I. Altered kinetics of electron transfer in phylloquinone biosynthetic pathway mutants studied by time-resolved optical, EPR and electrometric techniques, /. Biol. Chem., 275, 23,429, 2000. 

Johnson, T.W., Naithani, S., Zybailov, B., Jones, A.D., Golbeck, J.H., and Chitnis, P.R., The meriD and menE homologues code for 2-succinyl-6-hydroxyl-2,4-cyclohexadiene-l-carboxylate synthase and O-succinylbenzoic acid-CoA hgase in the phylloquinone biosynthetic pathway of Synechocystis sp. PCC 6803, Biochim. Biophys. Acta, 1557, 67, 2003. 

Johnson, T.W., Phylloquinone Biosynthetic Pathway, Ph.D. dissertation, Iowa State University,... 

Fig. 4. Branched biosynthetic pathways leading to phylloquinone (Vitamin Ki) and anthraquinones (e.g. lucidinprim-veroside).

The fact that phylloquinone and anthraquinone biosynthesis share a common biosynthetic pathway in the initial steps raises two questions how is the metabolic shift... 

FIGURE 119.2 Proposed biosynthetic pathway of phylloquinone in Synechocystis sp. PCC 6803. The genes responsible for the biosynthesis of menaquinone were initially described in E. colt. The homologs of these genes were identified in the genome sequence of Synechocystis sp. PCC 6803, and menA, menB, menD, menE, and menG were confirmed by experiment. 

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