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: 4-chlorosalicylate degradation, 5-chlorosalicylate degradation
|Superclasses:||Degradation/Utilization/Assimilation → Aromatic Compounds Degradation → Chloroaromatic Compounds Degradation|
|Degradation/Utilization/Assimilation → Chlorinated Compounds Degradation → Chloroaromatic Compounds Degradation|
Expected Taxonomic Range:
Pseudomonas reinekei is the most abundant organism in a four-member community that was isolated by continuous culture enrichment based on the ability to grow on 4-chlorosalicylate as a sole carbon source [Pelz99]. When grown in monocultures, the organism can use salicylate, 4-chlorosalicylate and 5-chlorosalicylate as the sole source of carbon and energy. During growth on chlorosalicylates there is no expression of enzymes of the chlorocatechol pathway, but the strains shows a high level of trans-dienelactone hydrolase [Pelz99].
The pathway for degradation of chlorosalicylates by this strain comprises an interesting patchwork of enzymes known to be involved in the 3-oxoadipate pathway and in the chlorocatechol pathway, as well as trans-dienelactone hydrolase [Nikodem03].
Chlorosalicylates are transformed by a salicylate 1-hydroxylase into 4-chlorocatechol, which is subject to ring cleavage by 4-methylcatechol 1,2-dioxygenase [multifunctional] to yield 3-chloro-cis,cis-muconate. The next enzyme in the pathway is muconate cycloisomerase I. This enzyme catalyzes the transformation of 3-chloro-cis,cis-muconate to protoanemonin, a dead-end metabolite that is rather toxic. However, this reaction proceeds via an intermediate - (+)-4-chloromuconolactone. The enzyme trans-dienelactone hydrolase acts on this intermediate, converting it to 2-maleylacetate in high efficiency, and preventing protoanemonin formation. 2-maleylacetate is reduced to 3-oxoadipate by maleylacetate reductase [Nikodem03], and the later is converted to TCA cycle intermediates (see 3-oxoadipate degradation).
The genes encoding the first three enzymes of this pathway were found in a single gene cluster that is expressed during growth on salicylate and chlorosalicylate [Camara07]. Three three genes were cloned, and their products were purified and characterized. These enzymes proved to be highly adapted towards 4-methylsalicylate transformation, having the highest affinities to intermediates of methylsalicylate degradation [Camara07]. The gene encoding trans-dienelactone hydrolase was discovered in a different part of the chromosome, and the purified protein was characterized as well [Camara08].
In a different study of the degradation of two monochlorodibenzofurans by a bacterial consortium, it was found that one organism degraded the monochlorodibenzofurans to chlorosalicylates, which were excreted, while another organism, identified as Pseudomonas moorei, mineralized the released chlorosalicylates by a pathway that included 4-chlorocatechol and protoanemonin [Wittich99]. Since no enzyme that can degraded protoanemonin is known, it is possible that it was only a byproduct, and that the degradation proceeded via the pathway described here [Nikodem03].
Camara07: Camara B, Bielecki P, Kaminski F, dos Santos VM, Plumeier I, Nikodem P, Pieper DH (2007). "A gene cluster involved in degradation of substituted salicylates via ortho cleavage in Pseudomonas sp. strain MT1 encodes enzymes specifically adapted for transformation of 4-methylcatechol and 3-methylmuconate." J Bacteriol 189(5);1664-74. PMID: 17172348
Camara08: Camara B, Marin M, Schlomann M, Hecht HJ, Junca H, Pieper DH (2008). "trans-Dienelactone hydrolase from Pseudomonas reinekei MT1, a novel zinc-dependent hydrolase." Biochem Biophys Res Commun 376(2);423-8. PMID: 18789896
Nikodem03: Nikodem P, Hecht V, Schlomann M, Pieper DH (2003). "New bacterial pathway for 4- and 5-chlorosalicylate degradation via 4-chlorocatechol and maleylacetate in Pseudomonas sp. strain MT1." J Bacteriol 185(23);6790-800. PMID: 14617643
Pelz99: Pelz O, Tesar M, Wittich RM, Moore ER, Timmis KN, Abraham WR (1999). "Towards elucidation of microbial community metabolic pathways: unravelling the network of carbon sharing in a pollutant-degrading bacterial consortium by immunocapture and isotopic ratio mass spectrometry." Environ Microbiol 1(2);167-74. PMID: 11207732
Wittich99: Wittich RM, Strompl C, Moore ER, Blasco R, Timmis KN (1999). "Interaction of Sphingomonas and Pseudomonas strains in the degradation of chlorinated dibenzofurans." J Ind Microbiol Biotechnol 23(4-5);353-358. PMID: 11423955
Blasco95: Blasco R, Wittich RM, Mallavarapu M, Timmis KN, Pieper DH (1995). "From xenobiotic to antibiotic, formation of protoanemonin from 4-chlorocatechol by enzymes of the 3-oxoadipate pathway." J Biol Chem 270(49);29229-35. PMID: 7493952
Broderick91: Broderick JB, O'Halloran TV (1991). "Overproduction, purification, and characterization of chlorocatechol dioxygenase, a non-heme iron dioxygenase with broad substrate tolerance." Biochemistry 30(29);7349-58. PMID: 1649626
Daubaras96: Daubaras DL, Saido K, Chakrabarty AM (1996). "Purification of hydroxyquinol 1,2-dioxygenase and maleylacetate reductase: the lower pathway of 2,4,5-trichlorophenoxyacetic acid metabolism by Burkholderia cepacia AC1100." Appl Environ Microbiol 62(11);4276-9. PMID: 8900023
Don85: Don RH, Weightman AJ, Knackmuss HJ, Timmis KN (1985). "Transposon mutagenesis and cloning analysis of the pathways for degradation of 2,4-dichlorophenoxyacetic acid and 3-chlorobenzoate in Alcaligenes eutrophus JMP134(pJP4)." J Bacteriol 161(1);85-90. PMID: 2981813
Endo05: Endo R, Kamakura M, Miyauchi K, Fukuda M, Ohtsubo Y, Tsuda M, Nagata Y (2005). "Identification and characterization of genes involved in the downstream degradation pathway of gamma-hexachlorocyclohexane in Sphingomonas paucimobilis UT26." J Bacteriol 187(3);847-53. PMID: 15659662
Halak07: Halak S, Basta T, Burger S, Contzen M, Wray V, Pieper DH, Stolz A (2007). "4-sulfomuconolactone hydrolases from Hydrogenophaga intermedia S1 and Agrobacterium radiobacter S2." J Bacteriol 189(19);6998-7006. PMID: 17660282
Kasberg95: Kasberg T, Daubaras DL, Chakrabarty AM, Kinzelt D, Reineke W (1995). "Evidence that operons tcb, tfd, and clc encode maleylacetate reductase, the fourth enzyme of the modified ortho pathway." J Bacteriol 177(13);3885-9. PMID: 7601858
Kasberg97: Kasberg T, Seibert V, Schlomann M, Reineke W (1997). "Cloning, characterization, and sequence analysis of the clcE gene encoding the maleylacetate reductase of Pseudomonas sp. strain B13." J Bacteriol 179(11);3801-3. PMID: 9171435
Kaschabek92: Kaschabek SR, Reineke W (1992). "Maleylacetate reductase of Pseudomonas sp. strain B13: dechlorination of chloromaleylacetates, metabolites in the degradation of chloroaromatic compounds." Arch Microbiol 158(6);412-7. PMID: 1482270
Kaschabek93: Kaschabek SR, Reineke W (1993). "Degradation of chloroaromatics: purification and characterization of maleylacetate reductase from Pseudomonas sp. strain B13." J Bacteriol 175(19);6075-81. PMID: 8407778
Matus03: Matus V, Sanchez MA, Martinez M, Gonzalez B (2003). "Efficient degradation of 2,4,6-Trichlorophenol requires a set of catabolic genes related to tcp genes from Ralstonia eutropha JMP134(pJP4)." Appl Environ Microbiol 69(12);7108-15. PMID: 14660355
Seibert93: Seibert V, Stadler-Fritzsche K, Schlomann M (1993). "Purification and characterization of maleylacetate reductase from Alcaligenes eutrophus JMP134(pJP4)." J Bacteriol 175(21);6745-54. PMID: 8226615
Seibert98: Seibert V, Kourbatova EM, Golovleva LA, Schlomann M (1998). "Characterization of the maleylacetate reductase MacA of Rhodococcus opacus 1CP and evidence for the presence of an isofunctional enzyme." J Bacteriol 180(14);3503-8. PMID: 9657989
vanderMeer91: van der Meer JR, Eggen RI, Zehnder AJ, de Vos WM (1991). "Sequence analysis of the Pseudomonas sp. strain P51 tcb gene cluster, which encodes metabolism of chlorinated catechols: evidence for specialization of catechol 1,2-dioxygenases for chlorinated substrates." J Bacteriol 173(8);2425-34. PMID: 2013566
Zylstra00: Zylstra, G. J., Bang, S.W., Newman, L.M., Perry, L.L. (2000). "Microbial degradation of mononitrophenols and mononitrobenzoates." p. 145-160. In J. C. Spain, J. B. Hughes, and H.-J. Knackmuss (ed.), Biodegradation of nitroaromatic compounds and explosives. Lewis Publishers, Boca Raton, Fla.
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