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MetaCyc Pathway: 4-hydroxybenzoate biosynthesis IV
Inferred from experiment

Enzyme View:

Pathway diagram: 4-hydroxybenzoate biosynthesis IV

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.

Synonyms: p-hydroxybenzoate biosynthesis IV

Superclasses: BiosynthesisAromatic Compounds Biosynthesis4-Hydroxybenzoate Biosynthesis

Some taxa known to possess this pathway include : Daucus carota, Lithospermum erythrorhizon, Solanum tuberosum

Expected Taxonomic Range: Viridiplantae

General Background

4-hydroxybenzoate (p-hydroxybenzoate) is widespread in plants. It is one of the major cell wall-bound phenolic acids that play a major role in plant defense against pathogens. It has also been identified as an important dietary anti-oxidant. In addition, 4-hydroxybenzoate is a key intermediate in the biosynthesis of ubiquinone-9 and several plant secondary metabolites, such as shikonin.

There are at least two biosynthetic routes leading to 4-hydroxybenzoate that have been proposed in plants: 1) the beta-oxidation route that converts 4-coumarate to 4- hydroxybenzoate via 4-coumaroyl-CoA; and 2) the non-beta oxidative pathway that converts 4-coumarate to 4- hydroxybenzoate via 4- hydroxybenzaldehyde. In plants, 4- hydorxybenzoate has an origin from phenylalanine where 4-coumarate is an intermediate and cleavage of two carbons from the 4-coumarate side-chain is required [Sircar08, Yazaki91, Loscher94]. In the beta-oxidation pathway, the side-chain shortening is analogous to fatty acid β-oxidation II (peroxisome) via CoA esters. In the non-oxidative pathway, the side-chain shortening is achieved through a lyase reaction that does not require CoA as a cofactor.

About This Pathway

The existence of the non-beta oxidation pathway has been reported in a number of plant species including, but not limited to, Lithospermum erythrorhizon and Daucus carota. In carrot, the accumulation of p-hydroxybenzoate in hairy root culture was dramatically increased by methyl jasmonate (MeJA) treatment. The enzymatic activities of the first and last enzymes of the biosynthetic pathway, phenylalanine ammonia-lyase (PAL) and 4-hydroxybenzaldehyde dehydrogenase (HBD) were coordinately increased by MeJA treatment [Sircar08].

Variants: 4-hydroxybenzoate biosynthesis I (eukaryotes), 4-hydroxybenzoate biosynthesis II (microbes), 4-hydroxybenzoate biosynthesis V, superpathway of 4-hydroxybenzoate biosynthesis (yeast)

Created 11-Feb-2010 by Zhang P, TAIR


Loscher94: Loscher R, Heide L (1994). "Biosynthesis of p-Hydroxybenzoate from p-Coumarate and p-Coumaroyl-Coenzyme A in Cell-Free Extracts of Lithospermum erythrorhizon Cell Cultures." Plant Physiol 106(1);271-279. PMID: 12232327

Sircar08: Sircar D, Mitra A (2008). "Evidence for p-hydroxybenzoate formation involving enzymatic phenylpropanoid side-chain cleavage in hairy roots of Daucus carota." J Plant Physiol 165(4);407-14. PMID: 17658659

Yazaki91: Yazaki, Kazufumi, Heide, Lutz, Tabata, Mamoru (1991). "Formation of p-hydroxybenzoic acid from p-coumaric acid by cell free extract of Lithospermum erythrorhizon cell cultures." Phytochemistry, 30(7):2233-2236.

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

Gunsalus53: Gunsalus CF, Stanier RY, Gunsalus IC (1953). "The enzymatic conversion of mandelic acid to benzoic acid. III. Fractionation and properties of the soluble enzymes." J Bacteriol 66(5);548-53. PMID: 13108854

Gunter53: Gunter SE (1953). "The enzymatic oxidation of p-hydroxymandelic acid to p-hydroxybenzoic acid." J Bacteriol 66(3);341-6. PMID: 13096484

Hegeman66: Hegeman GD (1966). "Synthesis of the enzymes of the mandelate pathway by Pseudomonas putida. I. Synthesis of enzymes by the wild type." J Bacteriol 91(3);1140-54. PMID: 5929747

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

Podstolski02: Podstolski A, Havkin-Frenkel D, Malinowski J, Blount JW, Kourteva G, Dixon RA (2002). "Unusual 4-hydroxybenzaldehyde synthase activity from tissue cultures of the vanilla orchid Vanilla planifolia." Phytochemistry 61(6);611-20. PMID: 12423881

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 Pathway Tools version 19.5 (software by SRI International) on Mon May 2, 2016, biocyc14.