Figure 6.

Genes with different phylogenetic affinities in the leucine/isoleucine biosynthesis operon. (a) Operon organization in different prokaryotic species. COG0028 - acetolactate synthase, large subunit; COG0440 - acetolactate synthase, small subunit; COG0059 - ketol-acid reductoisomerase; COG0129 - dihydroxyacid dehydratase; COG0119 - isopropylmalate synthases; COG0473 - isocitrate/isopropylmalate dehydrogenase; COG0066 - 3-isopropylmalate dehydratase, small subunit; COG0065 - 3-isopropylmalate dehydratase, large subunit. The designations are as in Figure 1a. For species abbreviations, see Materials and methods. (b-e) Unrooted maximum-likelihood tree for LeuA (b), LeuB (c), LeuC (d) and LeuD (e); the designations are as in Figure 1b.