| Record |
Author  |
Marin, M.; Perez-Pantoja, D.; Donoso, R.; Wray, V.; Gonzalez, B.; Pieper, D.H. |
| Title |
Modified 3-Oxoadipate Pathway for the Biodegradation of Methylaromatics in Pseudomonas reinekei MT1 |
Type |
|
| Year |
2010 |
Publication |
Journal Of Bacteriology |
Abbreviated Journal |
J. Bacteriol. |
| Volume |
192 |
Issue |
6 |
Pages |
1543-1552 |
| Keywords |
|
| Abstract |
Catechols are central intermediates in the metabolism of aromatic compounds. Degradation of 4-methyl-catechol via intradiol cleavage usually leads to the formation of 4-methylmuconolactone (4-ML) as a dead-end metabolite. Only a few microorganisms are known to mineralize 4-ML. The mml gene cluster of Pseudomonas reinekei MT1, which encodes enzymes involved in the metabolism of 4-ML, is shown here to encode 10 genes found in a 9.4-kb chromosomal region. Reverse transcription assays revealed that these genes form a single operon, where their expression is controlled by two promoters. Promoter fusion assays identified 4-methyl-3-oxoadipate as an inducer. Mineralization of 4-ML is initiated by the 4-methylmuconolactone methylisomerase encoded by mmlI. This reaction produces 3-ML and is followed by a rearrangement of the double bond catalyzed by the methylmuconolactone isomerase encoded by mmlJ. Deletion of mmlL, encoding a protein of the metallo-beta-lactamase superfamily, resulted in a loss of the capability of the strain MT1 to open the lactone ring, suggesting its function as a 4-methyl-3-oxoadipate enol-lactone hydrolase. Further metabolism can be assumed to occur by analogy with reactions known from the 3-oxoadipate pathway. mmlF and mmlG probably encode a 4-methyl-3-oxoadipyl-coenzyme A (CoA) transferase, and the mmlC gene product functions as a thiolase, transforming 4-methyl-3-oxoadipyl-CoA into methylsuccinyl-CoA and acetyl-CoA, as indicated by the accumulation of 4-methyl-3-oxoadipate in the respective deletion mutant. Accumulation of methylsuccinate by an mmlK deletion mutant indicates that the encoded acetyl-CoA hydrolase/transferase is crucial for channeling methylsuccinate into the central metabolism. |
| Address |
[Marin, Macarena; Pieper, Dietmar H.] Helmholtz Zentrum Infekt Forsch, Dept Microbial Pathogenesis, D-38124 Braunschweig, Germany, Email: dpi@helmholtz-hzi.de |
| Corporate Author |
|
Thesis |
|
| Publisher |
Amer Soc Microbiology |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-9193 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000274891300009 |
Approved |
|
| Call Number |
UAI @ eduardo.moreno @ |
Serial |
84 |
| Permanent link to this record |
