Origin of UlaGL from an ancient MBL RNase sequence. A. Structures of E. coli UlaG (PDB code 2wym, left), tRNA maturase RNase Z (PDB code 1y44, center) and B. anthracis ElaC homolog (PDB code 1zkp, right), with the conserved core domain shown in gray. Unique structural features are highlighted in green (UlaG), blue (1y44), and violet (1zkp). The Mn2+ ion (violet) in UlaG and the Zn2+ ions (orange) in the two RNases are shown as spheres. B. Multiple sequence alignment of UlaGL sequences (E. coli UlaG on top) and related RNase Z sequences obtained by structure-guided sequence searching and manual correction of the resultant alignments.
Fernandez et al. BMC Evolutionary Biology 2011 11:273 doi:10.1186/1471-2148-11-273