Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1099/mic.0.26774-0
Title (Primary) Regulation of catabolic enzymes during long-term exposure of Delftia acidovorans MC1 to chlorophenoxy herbicides
Author Benndorf, D.; Davidson, I.; Babel, W.
Source Titel Microbiology-SGM
Year 2004
Department UMB; PROTEOM
Volume 150
Issue 4
Page From 1005
Page To 1014
Language englisch
Abstract Delftia acidovorans MC1 is able to grow on chlorophenoxy herbicides such as 2,4-dichlorophenoxypropionic acid (2,4-DCPP) and 2,4-dichlorophenoxyacetic acid as sole sources of carbon and energy. High concentrations of the potentially toxic organics inhibit the productive degradation and poison the organism. To discover the target of chlorophenoxy herbicides in D. acidovorans MC1 and to recognize adaptation mechanisms, the response to chlorophenoxy acids at the level of proteins was analysed. The comparison of protein patterns after chemostatic growth on pyruvate and 2,4-DCPP facilitated the discovery of several proteins induced and repressed due to the substrate shifts. Many of the induced enzymes, for example two chlorocatechol 1,2-dioxygenases, are involved in the metabolism of 2,4-DCPP. A stronger induction of some catabolic enzymes (chlorocatechol 1,2-dioxygenase TfdCII, chloromuconate cycloisomerase TfdD) caused by an instant increase in the concentration of 2,4-DCPP resulted in increased rates of productive detoxification and finally in resistance of the cells. Nevertheless, the decrease of the (S)-2,4-DCPP-specific 2-oxoglutarate-dependent dioxygenase in 2D gels reveals a potential bottleneck in 2,4-DCPP degradation. Well-known heat-shock proteins and oxidative-stress proteins play a minor role in adaptation, because apart from DnaK only a weak or no induction of the proteins GroEL, AhpC and SodA was observed. Moreover, the modification of elongation factor Tu (TufA), a strong decrease of asparaginase and the induction of the hypothetical periplasmic protein YceI point to additional resistance mechanisms against chlorophenoxy herbicides.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=3971
Benndorf, D., Davidson, I., Babel, W. (2004):
Regulation of catabolic enzymes during long-term exposure of Delftia acidovorans MC1 to chlorophenoxy herbicides
Microbiology-(UK) 150 (4), 1005 - 1014