Dissimilatory arsenate reductase activity and arsenate-respiring bacteria in bovine rumen fluid, hamster feces, and the termite hindgut

FEMS Microbiology Ecology
By: , and 

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Abstract

Bovine rumen fluid and slurried hamster feces completely reduced millimolar levels of arsenate to arsenite upon incubation under anoxic conditions. This activity was strongly inhibited by autoclaving or aerobic conditions, and partially inhibited by tungstate or chloramphenicol. The rate of arsenate reduction was faster in feces from a population of arsenate-watered (100 ppm) hamsters compared to a control group watered without arsenate. Using radioisotope methods, arsenate reductase activity in hamster feces was also detected at very low concentrations of added arsenate (∼10 μM). Bacterial cultures were isolated from these materials, as well as from the termite hindgut, that grew using H2 as their electron donor, acetate as their carbon source, and arsenate as their respiratory electron acceptor. The three cultures aligned phylogenetically either with well-established enteric bacteria, or with an organism associated with feedlot fecal wastes. Because arsenite is transported across the gut epithelium more readily than arsenate, microbial dissimilatory reduction of arsenate in the gut may promote the body's absorption of arsenic and hence potentiate its toxicity.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Dissimilatory arsenate reductase activity and arsenate-respiring bacteria in bovine rumen fluid, hamster feces, and the termite hindgut
Series title FEMS Microbiology Ecology
DOI 10.1016/S0168-6496(02)00266-0
Volume 41
Issue 1
Year Published 2002
Language English
Publisher Oxford University Press
Contributing office(s) Toxic Substances Hydrology Program
Description 9 p.
First page 59
Last page 67