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E1 E2 metabolism v1

Metadata Updated: November 12, 2020

Feminization of male fish and the role of endocrine-active chemicals in this phenomenon has been an area of intense study for many years. Estrone (E1), a natural steroid, is found in aquatic environments sometimes at relatively high concentrations. However, E1 has been less thoroughly studied than 17β-estradiol (E2) or 17α-ethynylestradiol due in part to a relatively lower potency in metabolically-limited estrogen receptor (ER) binding/activation assays. Recent evidence suggests that in vivo biotransformation of E1 to E2 may occur in fathead minnows (Pimephales promelas) residing in environments with high concentrations of E1, such as near wastewater treatment plants. The enzymes likely responsible for this biotransformation, 17β-hydroxysteroid dehydrogenases (17βHSDs), have been well characterized in mammals but to a lesser extent in fish species. In the current study, a novel systematic analysis of amino acid sequence data from the National Center for Biotechnology Information database demonstrated that multiple 17βHSD isoforms are conserved across different fish species. Experimentally, we showed that metabolically-active hepatic cytosolic preparations from two commercially important salmonid species, rainbow trout and lake trout, biotransformed E1 to E2 to a degree sufficient to alter results of competitive ER binding assays. These results from in silico and in vitro analyses indicate E1 and biotransformation may play a significant role in the feminization of a variety of fish species in contaminated aquatic environments.

This dataset is associated with the following publication: Tapper, M., R. Kolanczyk, C. LaLone, J. Denny, and G. Ankley. Conversion of estrone to 17â-Estradiol: A potential confounding factor in assessing risks of environmental estrogens to fish. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 39(10): 2028–2040, (2020).

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Public: This dataset is intended for public access and use. License: See this page for license information.

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Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020

Metadata Source

Harvested from EPA ScienceHub

Additional Metadata

Resource Type Dataset
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Publisher U.S. EPA Office of Research and Development (ORD)
Data Last Modified 2020-04-14
Public Access Level public
Bureau Code 020:00
Schema Version
Harvest Object Id 7841ca56-37a0-4bab-b9f4-6cf9214e1106
Harvest Source Id 04b59eaf-ae53-4066-93db-80f2ed0df446
Harvest Source Title EPA ScienceHub
Program Code 020:095
Publisher Hierarchy U.S. Government > U.S. Environmental Protection Agency > U.S. EPA Office of Research and Development (ORD)
Related Documents
Source Datajson Identifier True
Source Hash 9f3045c1e552d8e2a9c0602309b5eb5557acd851
Source Schema Version 1.1

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