Arsenite Oxidation by Bacillus sp. Strain SeaH-As22w
Isolated from Coastal Seawater in Yeosu Bay

Chang, Jin-Soo; Kim, In S.

doi:2010.15.1.15

Environmental Engineering Research 2010;15(1): 15-21. DOI: https://doi.org/10.4491/eer.2010.15.1.015

Arsenite Oxidation by Bacillus sp. Strain SeaH-As22w Isolated from Coastal Seawater in Yeosu Bay

¹Molecular Biogeochemistry Laboratory, Department of Biological and Chemical Engineering, Yanbian University of Science and
²Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro,

Corresponding Author: In S. Kim ,Tel: +82-62-970-2436, Fax: +82-62-970-2434, Email: iskim@gist.ac.kr

Received: March 1, 2010; Accepted: March 15, 2010.

ABSTRACT

This study was conducted to evaluated seawater bacteria and their seasonal characteristics in the arsenic contaminated coastal seawater of Yeosu Bay, the Republic of Korea. Arsenite-oxidizing bacteria play an important role in the seawater of the arsenic contaminated bay, with a variety of arsenic resistance system (ars) genotypes being present during summer. Specifically, Bacillus sp. strain SeaH-As22w (FJ607342), isolated from the bay, were found to contain the arsB, arrA and aoxR type operons, which are involved in arsenic resistance. The isolated bacteria showed relatively high tolerance to sodium arsenite (III; NaAsO₂) at concentrations as high as 50 mM. Additionally, batch seawater experiments showed that Bacillus sp. strain SeaH-As22w completely oxidized 1 mM of As (III) to As (V) within 10 days. Ecologically, the arsenic-oxidizing potential plays an important role in arsenic toxicity and mobility in As-contaminated coastal seawater of Yeosu Bay during all seasons because it facilitates the activity of Bacillus sp. groups.

Keywords: ars genotype | Arsenic-oxidizing bacteria | Arsenic resistance system (ars) | Bacillus sp