Fig. 9.

Gene clustering and co-occurrence between CGFS Grxs and BolA. Analysis of gene co-occurence between CGFS Grx (COG0278) and BolA (COG0271) genes was performed using the “STRING” database (http://string.embl.de/) [15]. From 630 organisms analyzed, only two (Magnetococcus sp. and Giardia lamblia) possess only one of the two genes. Moreover, when CGFS Grx and BolA genes are clustering in all or only some prokaryote organisms of a given phylum, an asterisk has been added. The two genes are clustering in the large cyanobacteria and alpha-proteobacteria genus, whereas, except in a few cases, they do not cluster in beta- and gamma-proteobacteria. The analysis of the clustering of Grx genes was performed using “protein clusters” tool available at the NCBI webpage and the Microbial Genome Database (MGDB, http://mbgd.genome.ad.jp/)