Journal article
Enantioselective transport and biotransformation of chiral hydroxylated metabolites of polychlorinated biphenyls in whole poplar plants
Environmental science & technology, Vol.48(20), pp.12213-12220
10/21/2014
DOI: 10.1021/es503443e
PMCID: PMC4207536
PMID: 25238141
Abstract
Hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs) have been found to be ubiquitous in the environment due to the oxidative metabolism of their parent PCBs. With more polarity, OH-PCBs may be more toxic and mobile than their parent compounds. However, the behavior and fate of OH-PCBs have been neglected in the environment because they are not the original contaminants. Some of these hydroxylated metabolites are chiral, and chiral compounds can be used to probe biological metabolic processes. Therefore, chiral OH-PCBs were selected to study their uptake, translocation, transformation, and enantioselectivity in plants in this work. Poplars (Populus deltoides × nigra, DN34), a model plant with complete genomic sequence, were hydroponically exposed to 5-hydroxy-2,2',3,4',6-pentachlorobiphenyl (5-OH-PCB91) and 5-hydroxy-2,2',3,5',6-pentachlorobiphenyl (5-OH-PCB95) for 10 days. Chiral 5-OH-PCB91 and 5-OH-PCB95 were clearly shown to be sorbed, taken up, and translocated in whole poplars, and they were detected in various tissues of whole poplars. However, the enantioselectivity of poplar for 5-OH-PCB91 and 5-OH-PCB95 proved to be quite different. The second-eluting enantiomer of OH-PCB95, separated on a chiral column (Phenomenex Lux Cellulose-1), was enantioselectively removed in whole poplar. Enantiomeric fractions in the middle xylem, top bark, top xylem, and stem, reached 0.803 ± 0.022, 0.643 ± 0.110, 0.835 ± 0.087, and 0.830 ± 0.029, respectively. Therefore, 5-OH-PCB95 was significantly enantioselectively biotransformed inside poplar tissues, in contrast to nearly racemic mixtures of 5-OH-PCB95 remaining in hydroponic solutions. Unlike 5-OH-PCB95, 5-OH-PCB91 remained nearly racemic in most tissues of whole poplars during 10 day exposure, suggesting the enantiomers of 5-OH-PCB91 were equally transported and metabolized in whole poplars. This is the first evidence of enantioselectivity of chiral OH-PCBs and suggests that poplars can enantioselectively biotransform at least one chiral OH-PCB: namely, 5-OH-PCB95.
Details
- Title: Subtitle
- Enantioselective transport and biotransformation of chiral hydroxylated metabolites of polychlorinated biphenyls in whole poplar plants
- Creators
- Guangshu Zhai - Department of Civil and Environmental Engineering and IIHR Hydroscience and Engineering, The University of Iowa , Iowa City, Iowa 52242, United StatesSarah M GutowskiHans-Joachim LehmlerJerald L Schnoor
- Resource Type
- Journal article
- Publication Details
- Environmental science & technology, Vol.48(20), pp.12213-12220
- DOI
- 10.1021/es503443e
- PMID
- 25238141
- PMCID
- PMC4207536
- NLM abbreviation
- Environ Sci Technol
- ISSN
- 1520-5851
- eISSN
- 1520-5851
- Publisher
- United States
- Grant note
- P42 ES013661 / NIEHS NIH HHS P42ES013661 / NIEHS NIH HHS P30 ES005605 / NIEHS NIH HHS
- Language
- English
- Date published
- 10/21/2014
- Academic Unit
- Civil and Environmental Engineering; Occupational and Environmental Health; Iowa Neuroscience Institute; Iowa Superfund Research Program
- Record Identifier
- 9983991961302771
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