US EPA

1249005 

Journal Article 

Arsenic bioremediation potential of a new arsenite-oxidizing bacterium Stenotrophomonas sp. MM-7 isolated from soil 

Bahar, MM; Megharaj, M; Naidu, R 

2012 

Yes 

Biodegradation
ISSN: 0923-9820
EISSN: 1572-9729 

23 

6 

803-812 

English 

22760225 

10.1007/s10532-012-9567-4 

WOS:000309345100003 

A new arsenite-oxidizing bacterium was isolated from a low arsenic-containing (8.8 mg kg(-1)) soil. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the strain was closely related to Stenotrophomonas panacihumi. Batch experiment results showed that the strain completely oxidized 500 μM of arsenite to arsenate within 12 h of incubation in a minimal salts medium. The optimum initial pH range for arsenite oxidation was 5-7. The strain was found to tolerate as high as 60 mM arsenite in culture media. The arsenite oxidase gene was amplified by PCR with degenerate primers. The deduced amino acid sequence showed the highest identity (69.1 %) with the molybdenum containing large subunit of arsenite oxidase derived from Bosea sp. Furthermore the amino acids involved in binding the substrate arsenite, were conserved with the arsenite oxidases of other arsenite oxidizing bacteria such as Alcaligenes feacalis and Herminnimonas arsenicoxydans. To our knowledge, this study constitutes the first report on arsenite oxidation using Stenotrophomonas sp. and the strain has great potential for application in arsenic remediation of contaminated water. 

Arsenic; Arsenite oxidizing bacteria; Arsenite oxidase gene (aox); Detoxification