<p>Members are found in <taxon tax_id="34">Myxococcus xanthus</taxon> (six members), <taxon tax_id="35554">Geobacter sulfurreducens</taxon>, and <taxon tax_id="287">Pseudomonas aeruginosa</taxon>; a short protein homologous to the N-terminal region is found in <taxon tax_id="381">Rhizobium loti</taxon> (Mesorhizobium loti). All sequence are from Proteobacteria. The function is unknown.</p>