This pathway was completed by Jingfeng Feng, and updated by Lynda Ellis and Yingxu Liu, University of Minnesota.
Benzoate is a colorless or light yellow transparent liquid with very faint floral odor. It is an excellent solvent of synthetic musks and vanillin, and a fixative in bouguet perfumes. Benzoate is a common intermediate in the anaerobic metabolism of aromatic compounds, documented elsewhere in the UMBBD.
Two branches for aerobic benzoate metabolism are dioxygenation to form catechol, found in some bacteria (Harayama et al., 1991), and monooxygenation to form protocatechuate, used mostly by fungi (Sahasrabudhe et al., 1985).
Azoarcus evansii and some other bacteria use a third branch, starting with ligation with CoA to form benzoyl-CoA, and its monooxygenation to form the 2,3-epoxy compound. This is followed by hydrolysis of the epoxide, possibly with transient oxepin formation, to form 2,4-dehydroadipyl-CoA semialdehyde, and oxidation of this to 3,4-dehydroadipyl-CoA. This last compound is metabolized to succinyl-CoA and acetyl-CoA in several uncharacterized steps. This branch occurs in 4.5% of 649 bacteria whose genomes have been sequenced, compared to the 7% that contain the dioxygenase branch (Rather et al., 2010).
2-Chlorobenzoate and saccharin biodegradation is also included on this pathway map. 2-Chlorobenzene is used as a preservative for glues and paints and an intermediate in the manufacture of fungicides, dyes, pharmaceuticals and other organic chemicals. Saccharin, o-Benzosulfimide, is used as a flavoring agent and non-nutritive sweetener.
The following is a text-format benzoate degradation pathway map. Organisms which can initiate the pathway are given, but other organisms may also carry out later steps. Follow the links for more information on compounds or reactions.
Graphical Map (17k) | Graphical Map (13k) from the Benzonitrile Pathway Toluene Pathway Biphenyl Pathway Dichlobenil Pathway | | +---------------+---------------+-----------------------------------------+ | | | v v v Benzoate Benzoate Benzoate Pseudomonas putida Aspergillus niger Azoarcus evansii | Rhodotorula graminis | | | | | benzoate | benzoate | benzoate--CoA | dioxygenase | 4-monooxygenase | ligase | | | v v to the v cis-1,6-Dihydroxy-2,4- 4-Hydroxybenzoate ---> Vanillin Benzoyl-CoA cyclohexadiene-1- Pathway | carboxylic acid | Saccharin | | Sphingomonas xenophaga | benzoate cis-diol from the | benzoyl-CoA SKN | dehydrogenase Dichlobenil Pathway | monooxygenase | | | | | v | v +---------------> Catechol <------------------------ 2-Chlorobenzoate <---+ 2,3-Epoxybenzoyl-CoA saccharin | 2-chlorobenzoate Burkholderia cepacia 2CBS | dioxygenase | 1,2-dioxygenase Pseudomonas aeruginosa | 2,3-expoxy- | Aspergillus niger | benzoyl-CoA v Pseudomonas sp. CPE2 | hydrolase to the | Nitrobenzene Pathway v [3,4-Dehydroadipyl-] [CoA semialdehyde] | | 3,4-dehydroadipyl- | CoA semialdehyde | dehydrogenase | v 3,4-Dehydroadipyl-CoA | v A | +-------------+------------+ | | v v Succinyl-CoA Acetyl-CoA | | | | v v Intermediary Intermediary Metabolism Metabolism (KEGG) (KEGG)
Page Author(s): Jingfeng Feng, Lynda EllisContact Us
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