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Title: Biotransformation and Incorporation into Proteins along a Simulated Terrestrial Food Chain

Abstract

Selenium is an essential trace element in vertebrates, but there is a narrow concentration range between dietary requirement and toxicity threshold. Although a great deal is known about the biochemistry of Se from a nutritional perspective, considerably less attention has been focused on the specific biochemistry of Se as an environmental toxicant. Recent advances in hyphenated analytical techniques have provided the capability of quantifying specific chemical forms of Se in biological tissues as well as the distribution of Se among macromolecules. We applied liquid chromatography coupled to inductively coupled plasma mass spectrometry to investigate biotransformations of selenomethionine along a simulated terrestrial food chain consisting of selenomethionine exposed crickets (Acheta domesticus) fed to western fence lizards (Sceloporus occidentalis). Evidence was obtained for selenomethionine biotransformation as well as for sex-specific differences in the metabolism of Se compounds and their subsequent incorporation into proteins in the lizard. The results demonstrate the complexities involved in trophic transfer of Se due to the potential for extensive biotransformation and the species- and even sex-specific nature of these biotransformations.

Authors:
Publication Date:
Research Org.:
Savannah River Ecology Laboratory (SREL), Aiken, SC
Sponsoring Org.:
USDOE
OSTI Identifier:
908665
Report Number(s):
SREL-3034
Journal ID: ISSN 0013-936X; ESTHAG; TRN: US200722%%852
DOE Contract Number:
DE-FC09-07SR22506
Resource Type:
Journal Article
Resource Relation:
Journal Name: Environmental Science and Technology; Journal Volume: 41
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; BIOCHEMISTRY; CHROMATOGRAPHY; DISTRIBUTION; ELEMENTS; FENCES; FOOD CHAINS; LIZARDS; MASS SPECTROSCOPY; METABOLISM; PLASMA; PROTEINS; SELENIUM; TOXICITY; VERTEBRATES

Citation Formats

Unrine, J.M., B.P. Jackson and W.A. Hopkins. Biotransformation and Incorporation into Proteins along a Simulated Terrestrial Food Chain. United States: N. p., 2007. Web. doi:10.1021/es062073+.
Unrine, J.M., B.P. Jackson and W.A. Hopkins. Biotransformation and Incorporation into Proteins along a Simulated Terrestrial Food Chain. United States. doi:10.1021/es062073+.
Unrine, J.M., B.P. Jackson and W.A. Hopkins. Mon . "Biotransformation and Incorporation into Proteins along a Simulated Terrestrial Food Chain". United States. doi:10.1021/es062073+.
@article{osti_908665,
title = {Biotransformation and Incorporation into Proteins along a Simulated Terrestrial Food Chain},
author = {Unrine, J.M., B.P. Jackson and W.A. Hopkins},
abstractNote = {Selenium is an essential trace element in vertebrates, but there is a narrow concentration range between dietary requirement and toxicity threshold. Although a great deal is known about the biochemistry of Se from a nutritional perspective, considerably less attention has been focused on the specific biochemistry of Se as an environmental toxicant. Recent advances in hyphenated analytical techniques have provided the capability of quantifying specific chemical forms of Se in biological tissues as well as the distribution of Se among macromolecules. We applied liquid chromatography coupled to inductively coupled plasma mass spectrometry to investigate biotransformations of selenomethionine along a simulated terrestrial food chain consisting of selenomethionine exposed crickets (Acheta domesticus) fed to western fence lizards (Sceloporus occidentalis). Evidence was obtained for selenomethionine biotransformation as well as for sex-specific differences in the metabolism of Se compounds and their subsequent incorporation into proteins in the lizard. The results demonstrate the complexities involved in trophic transfer of Se due to the potential for extensive biotransformation and the species- and even sex-specific nature of these biotransformations.},
doi = {10.1021/es062073+},
journal = {Environmental Science and Technology},
number = ,
volume = 41,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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