FIG 5 .

ImcH homologues are widely distributed. Only proteins with at least 75% total of the sequence length of Geobacter sulfurreducens’ ImcH were included. Alignment was performed using the default settings in the ClustalO program, with FigTree v 1.4.0 used to generate the graphical representation of the alignment. Clusters with 50% or greater identity were collapsed. Clusters in which pure culture-based evidence for extracellular electron transfer has been found are shown in red, with the representative species/strain names also shown in red.