Chromosomal Integration of
            <i>tcb</i>
            Chlorocatechol Degradation Pathway Genes as a Means of Expanding the Growth Substrate Range of Bacteria To Include Haloaromatics

Klemba, Michael; Jakobs, Barbara D.; Wittich, Rolf-Michael; Pieper, Dietmar H.

doi:10.1128/aem.66.8.3255-3261.2000

Cited by 31 publications

(24 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The transfer of single copies of chlorocatechol genes (tcbR and tcbCDEF) originating from Pseudomonas sp. strain P51 (48) into Pseudomonas putida KT2442 did not result in the expected 3CB-degrading derivatives; multiple chromosomal copies (at least two) were needed to achieve this phenotype (20). Similarly, the transfer of single copies of tfd I or tfd II genes into the chromosome of R. eutropha JMP222 did not result in a 3CB-degrading phenotype, in contrast to the situation where those genes were introduced on a medium-copy-number vector (34).…”

Section: Discussionmentioning

confidence: 87%

Importance of DifferenttfdGenes for Degradation of Chloroaromatics byRalstonia eutrophaJMP134

et al. 2002

View full text Add to dashboard Cite

The tfdC I D I E I F I, and tfdD II C II E II F II gene modules of plasmid pJP4 of Ralstonia eutropha JMP134 encode complete sets of functional enzymes for the transformation of chlorocatechols into 3-oxoadipate, which are all expressed during growth on 2,4-dichlorophenoxyacetate (2,4-D). However, activity of tfd I -encoded enzymes was usually higher than that of tfd II -encoded enzymes, both in the wild-type strain grown on 2,4-D and in 3-chlorobenzoate-grown derivatives harboring only one tfd gene module. The tfdD II -encoded chloromuconate cycloisomerase exhibited special kinetic properties, with high activity against 3-chloromuconate and poor activity against 2-chloromuconate and unsubstituted muconate, thus explaining the different phenotypic behaviors of R. eutropha strains containing different tfd gene modules. The enzyme catalyzes the formation of an equilibrium between 2-chloromuconate and 5-chloro-and 2-chloromuconolactone and very inefficiently catalyzes dehalogenation to form trans-dienelactone as the major product, thus differing from all (chloro)muconate cycloisomerases described thus far.

show abstract

Section: Discussionmentioning

confidence: 87%

Importance of DifferenttfdGenes for Degradation of Chloroaromatics byRalstonia eutrophaJMP134

et al. 2002

View full text Add to dashboard Cite

show abstract

“…strain B13 (31) and the tcbCDEF gene cluster of Pseudomonas sp. strain P51 (17). In the latter cases, no explanation was provided.…”

Section: Discussionmentioning

confidence: 99%

Efficient Turnover of Chlorocatechols Is Essential for Growth of Ralstonia eutropha JMP134(pJP4) in 3-Chlorobenzoic Acid

et al. 2003

View full text Add to dashboard Cite

Ralstonia eutropha JMP134(pJP4) degrades 3-chlorobenzoate (3-CB) by using two not completely isofunctional, pJP4-encoded chlorocatechol degradation gene clusters, tfdC I D I E I F I and tfdD II C II E II F II . Introduction of several copies of each gene cluster into R. eutropha JMP222, which lacks pJP4 and thus accumulates chlorocatechols from 3-CB, allows the derivatives to grow in this substrate. However, JMP222 derivatives containing one chromosomal copy of each cluster did not grow in 3-CB. The failure to grow in 3-CB was the result of accumulation of chlorocatechols due to the limiting activity of chlorocatechol 1,2-dioxygenase (TfdC), the first enzyme in the chlorocatechol degradation pathway. Micromolar concentrations of 3-and 4-chlorocatechol inhibited the growth of strains JMP134 and JMP222 in benzoate, and cells of strain JMP222 exposed to 3 mM 3-CB exhibited a 2-order-of-magnitude decrease in viability. This toxicity effect was not observed with strain JMP222 harboring multiple copies of the tfdC I gene, and the derivative of strain JMP222 containing tfdC I -D I E I F I plus multiple copies of the tfdC I gene could efficiently grow in 3-CB. In addition, tfdC I and tfdC II gene mutants of strain JMP134 exhibited no growth and impaired growth in 3-CB, respectively. The introduction into strain JMP134 of the xylS-xylXYZL genes, encoding a broad-substrate-range benzoate 1,2-dioxygenase system and thus increasing the transformation of 3-CB into chlorocatechols, resulted in derivatives that exhibited a sharp decrease in the ability to grow in 3-CB. These observations indicate that the dosage of chlorocatechol-transforming genes is critical for growth in 3-CB. This effect depends on a delicate balance between chlorocatechol-producing and chlorocatechol-consuming reactions.

show abstract

“…This hypothesis has been shown to be correct in several cases (e.g. Brinkmann & Reineke, 1992 ;Klemba et al, 2000 ;Ravatn et al, 1998 ;Reineke & Knackmuss, 1979, 1980Rojo et al, 1987) and has given some insight into how a catabolic pathway may evolve in chloroaromatic-degrading bacteria.…”

Section: Abbreviationsmentioning

confidence: 99%

“…This is consistent with two recent observations from our laboratory -(i) that a JMP134 derivative harbouring a chromosomal integration of pJP4 is unable to grow on 3-CB and (ii) that the wild-type strain harbours five copies of pJP4 per genome (Trefault et al, 2002). The copy number of the clc genes and the tcb genes, which encode chlorocatechol pathways similar to that encoded by the tfd genes, has also been shown to be a limiting factor for growth of bacteria on chloroaromatic compounds (Klemba et al, 2000 ;Ravatn et al, 1998).…”

Section: T Ledger and Othersmentioning

confidence: 99%

Novel insights into the interplay between peripheral reactions encoded by xyl genes and the chlorocatechol pathway encoded by tfd genes for the degradation of chlorobenzoates by Ralstonia eutropha JMP134

et al. 2002

View full text Add to dashboard Cite

Many bacteria can grow on chloroaromatic pollutants because they can transform them into chlorocatechols, which are further degraded by enzymes of a specialized ortho-cleavage pathway. Ralstonia eutropha JMP134 is able to grow on 3-chlorobenzoate by using two pJP4-encoded, ortho-cleavage chlorocatechol degradation gene clusters (tfdC I D I E I F I and tfdD II C II E II F II ). Very little is known about the acquisition of new catabolic genes encoding enzymes that lead to the formation of chlorocatechols in R. eutropha JMP134. The effect on the catabolic properties of an R. eutropha JMP134 derivative that received the xylS-xylXYZL gene module, encoding the xylS-regulated expression of the broad-substrate-range toluate 1,2-dioxygenase (xylXYZ) and the 1,2-dihydro-1,2-dihydroxytoluate dehydrogenase (xylL) from pWW0, which allows the transformation of 4-chlorobenzoate into 4-chlorocatechol, was studied. Such a derivative could efficiently grow on 4-chlorobenzoate. Unexpectedly, this derivative also grew on 3,5-dichlorobenzoate, a substrate for XylXYZL but not an inducer of the XylS regulatory protein. The ability to grow on 4-chlorobenzoate or 3,5-dichlorobenzoate was also observed in derivatives of strain JMP134 containing the xyl gene module but lacking xylS, indicating the presence of an xylS-like element in R. eutropha with an inducer profile different from that of the pWW0-encoded regulator. Growth on 4-chlorobenzoate was also observed after introduction of the xyl gene module into strain JMP222, a JMP134 derivative lacking pJP4, but only if multiple copies of tfdC I D I E I F I or tfdD II C II E II F II were present. However, only the derivative containing multiple copies of tfdD II C II E II F II was able to grow on 3,5-dichlorobenzoate. These observations indicate that although the acquisition of new catabolic genes actually enhances the catabolic abilities of R. eutropha JMP134, these new properties are strongly influenced by the dosage of the tfd genes, the presence of a chromosomal xylS-like regulatory element and the different contributions of the tfd gene clusters. the chlorocatechol pathway allow bacteria to grow on chloroaromatic compounds. Therefore, it has been proposed that a wise combination of peripheral reactions with a chlorocatechol pathway should produce new or expanded catabolic properties in bacteria (Reineke, 1998). This hypothesis has been shown to be correct in several cases (e.g. Brinkmann & Reineke, 1992 ;Klemba et al., 2000 ; Ravatn et al., 1998 ;Reineke & Knackmuss, 1979, 1980Rojo et al., 1987) and has given some insight into how a catabolic pathway may evolve in chloroaromatic-degrading bacteria. KeywordsRalstonia eutropha JMP134 is well known for its catabolic properties toward chloroaromatic compounds. This bacterium grows on 2,4-dichlorophenoxyacetate (2,4-D) and 3-chlorobenzoate (3-CB), as well as other chloroaromatic pollutants (Cle! ment et al., 1995 ;Don & Pemberton, 1981 ; Pieper et al., 1988). The key catabolic abilities of R. eutropha JMP134 are encoded on the plasmid pJP...

show abstract

Chromosomal Integration of tcb Chlorocatechol Degradation Pathway Genes as a Means of Expanding the Growth Substrate Range of Bacteria To Include Haloaromatics

Cited by 31 publications

References 46 publications

Importance of DifferenttfdGenes for Degradation of Chloroaromatics byRalstonia eutrophaJMP134

Importance of DifferenttfdGenes for Degradation of Chloroaromatics byRalstonia eutrophaJMP134

Efficient Turnover of Chlorocatechols Is Essential for Growth of Ralstonia eutropha JMP134(pJP4) in 3-Chlorobenzoic Acid

Novel insights into the interplay between peripheral reactions encoded by xyl genes and the chlorocatechol pathway encoded by tfd genes for the degradation of chlorobenzoates by Ralstonia eutropha JMP134

Contact Info

Product

Resources

About