J.S. Blum
R.S. Oremland
S.E. Borglin
M.J. Herbel
2003
<p><span>A selenite-respiring bacterium, </span><i>Bacillus selenitireducens</i><span>, produced significant levels of Se(-II) (as aqueous HSe</span><sup>−</sup><span>) when supplied with Se(0). </span><i>B. selenitireducens</i><span> was also able to reduce selenite [Se(IV)] through Se(0) to Se(-II). Reduction of Se(0) by </span><i>B. selenitireducens</i><span> was more rapid in cells grown on colloidal sulfur [S(0)] or Se(IV) as their electron acceptor than for cell lines grown on fumarate. In contrast, three cultures of selenate-respiring bacteria, </span><i>Sulfurospirillum barnesii</i><span>, </span><i>B. arsenicoselenatis</i><span>, and </span><i>Selenihalanaerobacter shriftii</i><span> either were unable to reduce Se(0) to Se(-II) or had only a very limited capacity to achieve this reduction. Biological reduction of Se(0) to Se(-II) was observed during incubation of estuarine sediment slurries, while no such activity was noted in formalin-killed controls. The majority of the Se(-II) produced was found in the sediments as a solid precipitate of FeSe, rather than in solution as HSe</span><sup>−</sup><span>. These results demonstrate that certain anaerobic bacteria have the capacity to reduce Se(0) to Se(-II), providing a possible biological explanation for the occurrence of the selenide species in some sedimentary rocks.</span></p>
application/pdf
10.1080/713851163
en
Taylor & Francis
Reduction of elemental selenium to selenide: Experiments with anoxic sediments and bacteria that respire Se-oxyanions
article