Open AccessEvidence that the potential for dissimilatory ferric iron reduction is widespread among acidophilic heterotrophic bacteria
Author(s) -
Coupland Kris,
Johnson David Barrie
Publication year - 2008
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2007.00998.x
Subject(s) - ferrous , iron bacteria , schwertmannite , heterotroph , bacteria , chemistry , ferric , microbiology and biotechnology , environmental chemistry , biology , inorganic chemistry , goethite , genetics , organic chemistry , adsorption
Nineteen characterized strains and isolates of acidophilic heterotrophic bacteria were screened for their abilities to catalyse the reductive dissolution of the ferric iron mineral schwertmannite, under oxygen‐limiting conditions. Acidocella facilis , Acidobacterium capsulatum , and all of the Acidiphilium , Acidocella and Acidobacterium ‐like isolates that grew in liquid cultures were able to reduce iron. In contrast, neither Acidisphaera rubrifaciens nor three Acidisphaera ‐like isolates tested were found to have the capacity for dissimilatory iron reduction. One of two iron‐oxidizing Frateuria ‐like isolates also reduced iron under oxygen‐limiting conditions. Microbial dissolution of schwertmannite was paralleled with increased concentrations of soluble ferrous iron and sulfate in microbial cultures, together with increased pH values and decreased redox potentials. While dissimilatory ferric iron reduction has been described previously for Acidiphilium spp., this is this first report of this capacity in Acidocella and the moderate acidophile Acidobacterium . The finding has significant implications for understanding of the biogeochemistry of acidic environments.