Emerging investigator series: environment-specific auxiliary substrates tailored for effective cometabolic bioremediation of 1,4-dioxane

Deng, Daiyong; Pham, Dung Ngoc; Li, Mengyan

doi:10.1039/d2ew00524g

Cited by 3 publications

(8 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For instance, enhanced biodegradation of the pollutant 1,4-dioxane has previously been reported in the Arctic and American deep groundwater samples in the presence of different alcohols, which caused an overall boost in biomass (Deng et al, 2022;Li et al, 2010). In contrast, the presence of Group 2 auxiliary substrates, which possibly share the carbofuran pathway, might, over the long term, enhance carbofuran biodegradation kinetics through enhanced pathway expression or pathway induction (Deng et al, 2022;Sun et al, 2016). Slower degradation of Group 2 auxiliary substrates compared to carbofuran indicates that competitive inhibition does not play a role for carbofuran biodegradation in the presence of Group 2 auxiliary substrates.…”

Section: Biodegradation Mechanisms Of the Different Transformation Gr...mentioning

confidence: 99%

“…In particular, auxiliary substrates that are degraded by the same pathway as OMPs can be beneficial for bioremediation purposes (Deng et al, 2022; Sun et al, 2016). Such substrates can induce and maintain the OMP biodegradation pathway and thus enhance biodegradation kinetics (Deng et al, 2022; Sun et al, 2016), when substrate competition for the degrading enzymes is minor (Rentz et al, 2004). For instance, a recent study found that dioxane biodegradation by Azoarcus sp.…”

Section: Introductionmentioning

confidence: 99%

“…Beyond assessing their biodegradability, investigating the biotransformation mechanisms of growth‐supporting DOM constituents is important as they can impact OMP removal. In particular, auxiliary substrates that are degraded by the same pathway as OMPs can be beneficial for bioremediation purposes (Deng et al, 2022; Sun et al, 2016). Such substrates can induce and maintain the OMP biodegradation pathway and thus enhance biodegradation kinetics (Deng et al, 2022; Sun et al, 2016), when substrate competition for the degrading enzymes is minor (Rentz et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

“…For instance, a recent study found that dioxane biodegradation by Azoarcus sp. DD4 was promoted through pathway induction by the auxiliary substrate propane in microcosm experiments representing different freshwater environments (Deng et al, 2022). Conversely, if OMPs and auxiliary substrates are degraded by different pathways, the presence of auxiliary substrates might increase the growth of the OMP degrader, but not the expression of the OMP biodegradation pathway (Cheyns et al, 2012; Deng et al, 2022; Li et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

“…DD4 was promoted through pathway induction by the auxiliary substrate propane in microcosm experiments representing different freshwater environments (Deng et al, 2022). Conversely, if OMPs and auxiliary substrates are degraded by different pathways, the presence of auxiliary substrates might increase the growth of the OMP degrader, but not the expression of the OMP biodegradation pathway (Cheyns et al, 2012; Deng et al, 2022; Li et al, 2010). Such auxiliary substrates can promote OMP bioremediation through enhanced overall growth as long as they do not repress the OMP biodegradation pathway (Cheyns et al, 2012; Li et al, 2017; Rentz et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Coupling pathway prediction and fluorescence spectroscopy to assess the impact of auxiliary substrates on micropollutant biodegradation

Schittich,

Fenner,

Stedmon

et al. 2024

Environmental Microbiology

View full text Add to dashboard Cite

Some bacteria can degrade organic micropollutants (OMPs) as primary carbon sources. Due to typically low OMP concentrations, these bacteria may benefit from supplemental assimilation of natural substrates present in the pool of dissolved organic matter (DOM). The biodegradability of such auxiliary substrates and the impacts on OMP removal are tightly linked to biotransformation pathways. Here, we aimed to elucidate the biodegradability and effect of different DOM constituents for the carbofuran degrader Novosphingobium sp. KN65.2, using a novel approach that combines pathway prediction, laboratory experiments, and fluorescence spectroscopy. Pathway prediction suggested that ring hydroxylation reactions catalysed by Rieske‐type dioxygenases and flavin‐dependent monooxygenases determine the transformability of the 11 aromatic compounds used as model DOM constituents. Our approach further identified two groups with distinct transformation mechanisms amongst the four growth‐supporting compounds selected for mixed substrate biodegradation experiments with the pesticide carbofuran (Group 1: 4‐hydroxybenzoic acid, 4‐hydroxybenzaldehyde; Group 2: p‐coumaric acid, ferulic acid). Carbofuran biodegradation kinetics were stable in the presence of both Group 1 and Group 2 auxiliary substrates. However, Group 2 substrates would be preferable for bioremediation processes, as they showed constant biodegradation kinetics under different experimental conditions (pre‐growing KN65.2 on carbofuran vs. DOM constituent). Furthermore, Group 2 substrates were utilisable by KN65.2 in the presence of a competitor (Pseudomonas fluorescens sp. P17). Our study thus presents a simple and cost‐efficient approach that reveals mechanistic insights into OMP‐DOM biodegradation.

show abstract