FIG 7 .

Gene clusters encoding putative porin-multiheme cytochrome c complex (PCC). The IMG gene locus tag for the first gene in each presented gene cluster is indicated in parentheses. The vertical line indicates the end of a contig, and horizontal lines below gene designations indicate predicted cellular locations of their encoded proteins. These putative PCC genes are in 18.1-, 9.0-, 6.1-, 18.4-, 70.0-, 10.6-, and 10.8-kbp-long contigs. A hypothesized model of extracellular electron transfer is shown on the right, with yellow arrows indicating electron flows. “IM” and “OM” refer to inner and outer membranes, respectively, “ET in IM” refers to electron transfer in the inner membrane, and “EA_(ox)” and “EA_(red)” refer to oxidized and reduced forms of the electron acceptor, respectively.