This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
|Superclasses:||Biosynthesis → Cofactors, Prosthetic Groups, Electron Carriers Biosynthesis → Polyprenyl Biosynthesis|
Some taxa known to possess this pathway include : Allochromatium vinosum , Bacillus alcalophilus , Bacillus amyloliquefaciens , Bacillus badius , Bacillus cereus , Bacillus circulans , Bacillus coagulans , Bacillus firmus , Bacillus licheniformis , Bacillus megaterium , Bacillus psychrosaccharolyticus , Bacillus pumilus , Bacillus racemilacticus , Bacillus subtilis , Bacillus thuringiensis , Brochothrix thermosphacta , Chlorobaculum thiosulfatiphilum , Desulfotomaculum nigrificans , Desulfuromonas acetoxidans , Exiguobacterium acetylicum , Flexibacter elegans , Geobacillus stearothermophilus , Listeria grayi , Pimelobacter simplex , Psychrobacillus insolitus , Sporolactobacillus inulinus , Sporosarcina ureae , Staphylococcus aureus , Staphylococcus capitis , Staphylococcus cohnii , Staphylococcus epidermidis , Staphylococcus haemolyticus , Staphylococcus hominis , Staphylococcus saprophyticus , Staphylococcus simulans , Staphylococcus warneri , Thermoplasma acidophilum , [Bacillus] aminovorans , [Brevibacterium] halotolerans
In this pathway multiple units of isopentenyl diphosphate (IPP) undergo a series of polymerizations to form a polyisoprenoid chain.
Additional isoprenoid units are added to a maximal length that is determined by the specific enzyme. Most organisms generate polyprenyl chains of predominantly one length. Once completed, the polyprenyl chain is incorporated into other molecules, such as quinones. The enzyme that attaches the polyprenyl chain to the quinone precursor molecule does not have a preference towards a particular length. Thus, the length of the polyprenyl chain in the mature quinone molecule is determined by the predominant polyprenyl diphosphate synthase enzyme of the organism.
In most organisms there is one type of a predominant quinone, with a specific polyprenyl chain length. However, most organisms also have minor amounts of quinones with a different polyprenyl chain length.
Organisms whose main quinone contains a chain of 7 isoprenyl units include some Gram-negative bacteria (for example, the gliding bacterium Flexibacter elegans and the phototroph Allochromatium vinosum strain D), but mostly Gram-positive bacteria, such as many members of the Bacillus
Superpathways: superpathway of menaquinol-7 biosynthesis
Zhang98e: Zhang YW, Koyama T, Marecak DM, Prestwich GD, Maki Y, Ogura K (1998). "Two subunits of heptaprenyl diphosphate synthase of Bacillus subtilis form a catalytically active complex." Biochemistry 37(38);13411-20. PMID: 9748348
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