Metabolic Modeling Tutorial
discounted EARLY registration ends Dec 31, 2014
Metabolic Modeling Tutorial
discounted EARLY registration ends Dec 31, 2014
Metabolic Modeling Tutorial
discounted EARLY registration ends Dec 31, 2014
Metabolic Modeling Tutorial
discounted EARLY registration ends Dec 31, 2014
Metabolic Modeling Tutorial
discounted EARLY registration ends Dec 31, 2014

MetaCyc Pathway: rhodoquinone-10 biosynthesis

Enzyme View:

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 Quinol and Quinone Biosynthesis Rhodoquinone Biosynthesis

Some taxa known to possess this pathway include ? : Arenicola marina , Crassostrea gigas , Fasciola hepatica , Lymnaea stagnalis , Mytilus edulis , Rhodospirillum rubrum

Expected Taxonomic Range: Bivalvia , Gastropoda , Ostreoida , Platyhelminthes , Polychaeta , Rhodospirillales

General Background

Rhodoquinone (RQ) is a modified ubiquinone, where the methoxyl group in position 3 is replaced by an amino group. The compound was originally isolated from Rhodospirillum rubrum [Glover62, Moore65, Parson65], where is it used for the reduction of fumarate to succinate under anaerobic conditions.

Rhodoquinone is not limited to prokaryotes. It was soon discovered that some eukaryotic parasites such as the nematodes Ascaris suum and Ascaris lumbricoides [Ozawa69, Kassner75], as well as parasitic helminths [Allen73] also contain rhodoquinone, which is essential for fumarate reduction under anaerobic conditions [Kita88]. Later it was shown that rhodoquinone is present in all eukaryotes that reduce fumarate during anoxia, including freshwater snails, mussels, lugworms, and oysters [Van95b].

It has been suggested that rhodoquinone is synthesized from ubiquinone [Parson65, Moore65]. However, the enzyme(s) that catalyze this conversion have not been described.

About This Pathway

The original rhodoquinone isolated from Rhodospirillum rubrum was rhodoquinone-10, with a side chain containing 10 prenyl units (as reported in [Moore65]). rhodoquinone-10 was also detected in several eukaryotes that are subjected to anaerobic conditions, including the liver fluke Fasciola hepatica [Van96a], the mussel Mytilus edulis, the lugworm Arenicola marina, the oyster Crassostrea gigas, and the snail Lymnaea stagnalis [Van95b].

Created 24-Apr-2008 by Caspi R , SRI International


Allen73: Allen PC (1973). "Helminths: comparison of their rhodoquinone." Exp Parasitol 34(2);211-9. PMID: 4795616

Glover62: Glover, J., Threlfall, D. R. (1962). "A new quinone (rhodoquinone) related to ubiquinone in the photosynthetic bacterium Rhodospirillum rubrum." Biochem. J. 85:149.

Kassner75: Kassner EG, Klotz DH (1975). "Cholecystitis and calculi in a diverticulum of the gallbladder." J Pediatr Surg 10(6);967-8. PMID: 811785

Kita88: Kita K, Takamiya S, Furushima R, Ma YC, Suzuki H, Ozawa T, Oya H (1988). "Electron-transfer complexes of Ascaris suum muscle mitochondria. III. Composition and fumarate reductase activity of complex II." Biochim Biophys Acta 935(2);130-40. PMID: 2843227

Moore65: Moore HW, Folkers K (1965). "Coenzyme Q. LXII. Structure and synthesis of rhodoquinone, a natural aminoquinone of the coenzyme Q group." J Am Chem Soc 87;1409-10. PMID: 14293762

Ozawa69: Ozawa H, Sato M, Natori S, Ogawa H (1969). "Occurrence of rhodoquinone-9 in the muscle of Ascaris lumbricolides var. suis." Experientia 25(5);484-5. PMID: 5796154

Parson65: Parson WW, Rudney H (1965). "The biosynthesis of ubiquinone and rhodoquinone from p-hydroxybenzoate and p-hydroxybenzaldehyde in Rhodospirillum rubrum." J Biol Chem 240;1855-63. PMID: 14285535

Van95b: Van Hellemond JJ, Klockiewicz M, Gaasenbeek CP, Roos MH, Tielens AG (1995). "Rhodoquinone and complex II of the electron transport chain in anaerobically functioning eukaryotes." J Biol Chem 270(52);31065-70. PMID: 8537365

Van96a: Van Hellemond JJ, Luijten M, Flesch FM, Gaasenbeek CP, Tielens AG (1996). "Rhodoquinone is synthesized de novo by Fasciola hepatica." Mol Biochem Parasitol 82(2);217-26. PMID: 8946387

Other References Related to Enzymes, Genes, Subpathways, and Substrates of this Pathway

Latendresse13: Latendresse M. (2013). "Computing Gibbs Free Energy of Compounds and Reactions in MetaCyc."

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by SRI International Pathway Tools version 18.5 on Thu Nov 27, 2014, BIOCYC14B.