Growth on Phenol at Chemostress Levels Amplifies the Expression of the Phenol Degradation Pathway in Acinetobacter calcoaceticus

Abstract

Bacteria often use pollutants as sole carbon and energy sources. However, if they are toxic and the concentrations are high these compounds inhibit growth, and eventually poison the biocatalysts. In order to identify mechanisms contributing to stability, the protein patterns of Acinetobacter calcoaceticus during growth on potentially toxic phenol were analysed using two-dimensional gel electrophoresis. Enzymes involved in the catabolism or assimilation of phenol, such as phenol monooxygenase and catechol 1,2-dioxygenase, were induced at a more than twofold level in response to long-term exposure to high concentrations of the compound serving as the sole carbon and energy source. This would have clear adaptive benefits, since increased rates of consumption of phenol would reduce the susceptibility of Acinetobacter calcoaceticus to phenol poisoning. In contrast, transient induction of only one heat shock protein and one oxidative stress protein was detected during long-term exposure to high concentrations of phenol.

Acinetobacter calcoaceticus CSY-P13 Mitigates Stress of Ferulic and p-Hydroxybenzoic Acids in Cucumber by Affecting Antioxidant Enzyme Activity and Soil Bacterial Community

“…CAT in a phenol-degrading strain of A. calcoaceticus plays a role in short-term adaptation of this strain to stress induced by phenol ( Benndorf et al, 2004 ). In CSY-P13 exposed to FA and PHBA, the activities of SOD, CAT, APX, and DHAR were elevated.…”

Phenol degradation by Aureobasidium pullulans FE13 isolated from industrial effluents

“…This enables the cell to express the respective pathways only in the presence of an inducing substrate. In addition, proteome analysis has suggested that the induction of catabolic enzymes during growth on high concentrations of the potentially toxic organics as phenol could be a component of the response to chemostress in microorganisms which is able to metabolize these compounds [5]. This induction probably provides resistance against phenol poisoning by lowering the intracellular concentrations of phenol and catechol.…”

Adaptations in microbiological populations exposed to dinitrophenol and other chemical stressors

“…The reduction in biomass attributable to transfer alone is equated with the biomass reduction in the control vessels for the same phase in the experiment. For V 12 , the value of f t_12 is thus equated with f t_10 , which is determined from biomass reduction observed in the control vessels V 00 ! V 10 .…”

“…Microorganisms that are effective at degrading pollutants can be stressed by exposure to these chemicals, as has been observed for Methylocystis sp. M and trichloroethylene [11], Acinetobacter calcoaceticus and phenol [12], Pseudomonas sp. B4 and polychlorinated biphenyls [13], and Pseudomonas putida KT2440 and toluene [14].…”