Open AccessExpression of acetate permease‐like ( apl ) genes in subsurface communities of Geobacter species under fluctuating acetate concentrations
Author(s) -
Elifantz Hila,
N'Guessan Lucie A.,
Mouser Paula J.,
Williams Kenneth H.,
Wilkins Michael J.,
Risso Carla,
Holmes Dawn E.,
Long Philip E.,
Lovley Derek R.
Publication year - 2010
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.2010.00907.x
Subject(s) - bioremediation , geobacter , biology , chemostat , uranyl acetate , environmental chemistry , microbiology and biotechnology , contamination , chemistry , bacteria , ecology , botany , biofilm , genetics , ultrastructure
The addition of acetate to uranium‐contaminated aquifers in order to stimulate the growth and activity of Geobacter species that reduce uranium is a promising in situ bioremediation option. Optimizing this bioremediation strategy requires that sufficient acetate be added to promote Geobacter species growth. We hypothesized that under acetate‐limiting conditions, subsurface Geobacter species would increase the expression of either putative acetate symporters genes ( apl I and apl II). Acetate was added to a uranium‐contaminated aquifer (Rifle, CO) in two continuous amendments separated by 5 days of groundwater flush to create changing acetate concentrations. While the expression of apl I in monitoring well D04 (high acetate) weakly correlated with the acetate concentration over time, the transcript levels for this gene were relatively constant in well D08 (low acetate). At the lowest acetate concentrations during the groundwater flush, the transcript levels of apl II were the highest. The expression of apl II decreased 2–10‐fold upon acetate reintroduction. However, the overall instability of acetate concentrations throughout the experiment could not support a robust conclusion regarding the role of apl genes in response to acetate limitation under field conditions, in contrast to previous chemostat studies, suggesting that the function of a microbial community cannot be inferred based on lab experiments alone.