Sequence alignment of Bacillus d-AATs. Abbreviations: G.SK1, G. toebii SK1; G.KLS1, Geobacillus sp. strain KLS1; G.kau, G. kaustophilus; B.YM1, Bacillus sp. strain YM1, B.sph, B. sphaericus; B.sub, B. subtilis; B.lic, B. licheniformis; B.cer, B. cereus; B.ant, B. anthracis; B.hal, B. halodurans; L.mon, Listeria monocytogenes; S.hae, Staphylococcus haemolyticus. The conserved residues are shaded dark, while similar residues are shaded light. The asterisk indicates the lysine residue that forms a sciff base with pyridoxal 5′-phosphate.