alexa Bacterial populations associated with the oxidation and reduction of arsenic in an unsaturated soil.
Environmental Sciences

Environmental Sciences

Journal of Bioremediation & Biodegradation

Author(s): Macur RE, Jackson CR, Botero LM, McDermott TR, Inskeep WP

Abstract Share this page

Abstract Microbial populations responsible for the oxidation and reduction of As were examined in unsaturated (aerobic) soil columns treated with 75 microM arsenite [As(III)] or 250 microM arsenate [As(V)]. Arsenite [As(III)] was rapidly oxidized to As(V) via microbial activity, whereas no apparent reduction of As(V) was observed in the column experiments. Eight aerobic heterotrophic bacteria with varying As redox phenotypes were isolated from the same columns. Three isolates, identified as Agrobacterium tumefaciens-, Pseudomonas fluorescens-, and Variovorax paradoxus-like organisms (based on 16S sequence), were As(III) oxidizers, and all were detected in community DNA fingerprints generated by PCR coupled with denaturing gradient gel electrophoresis. The five other isolates were identified (16S gene sequence) as A. tumefaciens, Flavobacterium sp., Microbacterium sp., and two Arthrobacter sp. -like organisms and were shown to rapidly reduce As(V) under aerobic conditions. Although the two A. tumefaciens-like isolates exhibited opposite As redox activity,their 16S rDNA sequences (approximately 1400 bp) were 100\% identical, and both were shown to contain putative arsC genes. Our results support the hypothesis that bacteria capable of either oxidizing As(III) or reducing As(V) coexist and are ubiquitous in soil environments, suggesting that the relative abundance and metabolic activity of specific microbial populations plays an important role in the speciation of inorganic As in soil pore waters.
This article was published in Environ Sci Technol and referenced in Journal of Bioremediation & Biodegradation

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

  • 6th World Congress on Biofuels and Bioenergy
    Sep 5-6, 2017 London, UK
  • 6th World Congress on Biopolymers
    September 7-9, 2017 Paris, France
  • 7th International Conference and Exhibition on Biopolymers and Bioplastics
    October 19-21, 2017 San Francisco, USA

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version