FIG 5.

Reduction of Fe(III) in ferrihydrite in an abiotic control experiment and in incubations of S. deleyianum supplied with 5 mM acetate as a carbon source, 10 mM formate as an electron donor, and 0.1 mM thiosulfate as an electron acceptor. Error bars represent standard deviations based on three replicates. For the setup with 2 mM cysteine and a 1% inoculum, results of six experiments are shown, one experiment with three replicates and three additional independent experiments. For the abiotic setup with 2 mM cysteine, results of three independent experiments are shown. w/o, without; inoc., inoculum.