ISSN: 1546-962X
CODEN: JAIOAD
Published Online: 29 May 2009
Page Count: 6

Isolation of Tributyltin-Degrading Bacteria Citrobacter braakii and Enterobacter cloacae from Butyltin-Polluted Sediment

Sakultantimetha, A.
Dept. of Civil Engineering, David Livingstone Centre for Sustainability, Univ. of Strathclyde, Glasgow G1 1XN, Scotland

Keenan, H. E.
Dept. of Civil Engineering, David Livingstone Centre for Sustainability, Univ. of Strathclyde, Glasgow G1 1XN, Scotland

Dyer, M.
School of Engineering, Faculty of Engineering, Mathematics and Science, Trinity College Dublin, College Green, Dublin 2

Beattie, T. K.
Dept. of Civil Engineering, David Livingstone Centre for Sustainability, Univ. of Strathclyde, Glasgow G1 1XN, Scotland

Bangkedphol, S.
Dept. of Civil Engineering, David Livingstone Centre for Sustainability, Univ. of Strathclyde, Glasgow G1 1XN, Scotland

Songsasen, A.
Dept. of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Kasetsart Univ., Bangkok,

(Received 15 September 2008; accepted 14 April 2009)

Abstract

Tributyltin compound (TBT) released into the aquatic environment is generally degraded by bacteria in water and sediment. The isolation of TBT-degrading bacteria from TBT polluted sediment leads to the indication of specific potential TBT degraders. Two new strains of bacteria designated as B2 and B3 were successfully isolated using glycerol medium containing tributyltin chloride (TBTC) at 130 μM from contaminated sediment collected from Bowling Basin in Glasgow. The observed degradation after 14 days of the microcosm from the sediment and the isolated bacteria were investigated at an initial concentration of 1 μM TBTC. It was found that TBT was degraded by the bacterial strains B2 and B3 at 8.3 and 16.9 %, respectively. The results indicate that B2 and B3 are effective as TBT degraders. EC₅₀ of B2 and B3 in water were 88.73 and 112.53 μM TBTC, which were significantly higher than the concentration of TBT measured at the basin, suggesting a low effect of TBT on the growth and activity of bacteria. After identification using API 20E and 16S sequencing, the bacterial isolate strain B2 is Citrobacter braakii and B3 is Enterobacter cloacae. Therefore, this study has discovered two species of high resistance TBT degrader which have never been previously studied or isolated based upon TBT degradation ability.

Keywords:
tributyltin, isolation, degradation, Citrobacter braakii, Enterobacter cloacae

Paper ID: JAI102120
DOI: 10.1520/JAI102120
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