Multiple sequence alignments (Clustal) of the genes encoding the small subunits of the Group 5 [NiFe]-hydrogenases in P. methylaliphatogenes (PYK22_03064), Solibacter usitatus (Acid_6555), Mycobacterium smegmatis (MSMEG_2720), Streptomyces avermitilis (SAV_7367), and Ralstonia eutropha (PHG064). The subunit ligates a 3Cys1Asp[4Fe4S]proximal (ligands highlighted in green), 4Cys[4Fe4S]medial cluster (ligands highlighted in blue), and a 3Cys1His[4Fe4S]distal cluster (ligands highlighted in pink).