Legend to Figure 2

Alignment of protein phosphatases from , lambda [64], with E. coli diadenosine tetra-phosphatase and representative sequences from Figure 1. The shading protocol is identical to that described in the legend to Figure 1. The line Figure 1 Numbers cross-references positions in this alignment with Figure 1. This alignment has been optimised for the sequences that are shown, as a consequence, the alignment between positions 50 and 60 differs slightly from that shown in Figure 1. The Leu at position 43 (position 67 in Figure 1) is shown as an identity since the only sequence without Leu at this position is PPT (Val). Similarly, the Leu at position 80 (position 121 in Figure 1) is also shown as an identity, since the only sequence withou Leu at this position is PPT (Phe).