US EPA

1003602 

Journal Article 

Oxidation of arsenite by two β-proteobacteria isolated from soil 

Bachate, SP; Khapare, RM; Kodam, KM 

2012 

Yes 

Applied Microbiology and Biotechnology
ISSN: 0175-7598
EISSN: 1432-0614 

93 

5 

2135-2145 

English 

21983709 

10.1007/s00253-011-3606-7 

WOS:000300657900031 

Two heterotrophic As(III)-oxidizing bacteria, SPB-24 and SPB-31 were isolated from garden soil. Based on 16S rRNA gene sequence analysis, strain SPB-24 was closely related to genus Bordetella, and strain SPB-31 was most closely related to genus Achromobacter. Both strains exhibited high As(III) (15 mM for SPB-24 and 40 mM for SPB-31) and As(V) (>300 mM for both strains) resistance. Both strains oxidized 5 mM As(III) in minimal medium with oxidation rate of 554 and 558 μM h(-1) for SPB-24 and SPB-31, respectively. Washed cells of both strains oxidized As(III) over broad pH and temperature range with optimum pH 6 and temperature 42°C for both strains. The As(III) oxidation kinetic by washed cells showed K (m) and V (max) values of 41.7 μM and 1,166 μM h(-1) for SPB-24, 52 μM and 1,186 μM h(-1) for SPB-31. In the presence of minimal amount of carbon source, the strains showed high As(III) oxidation rate and high specific arsenite oxidase activity. The ability of strains to resist high concentration of arsenic and oxidize As(III) with highest rates reported so far makes them potential candidates for bioremediation of arsenic-contaminated environment. 

Arsenite oxidation; Achromobacter; Bordetella