Distribution of rTCA enzymes in Aquificales.

Numbers in each column represent the length of the enzyme in terms of amino acid residues, and the numbers in parentheses are the sequence similarities relative to the T. thermophilus version of those enzymes. Entries ** are for species that have only one copy of that enzyme class, which are aligned with the type to which it has greatest sequence similarity (sequence similarity for alternate alignment also shown for comparison). Families: I - Aquificaceae, II - Hydrogenothermaceae, III - Desulfurothermaceae. Abbreviations: ICDH, isocitrate dehydrogenase; BC, biotin carboxylase; -CoA synthase; LS, large subunit; SS, small subunit; PYR, pyruvate; AKG, -ketoglutarate; SUC-, succinyl-; CIT-, citryl.