Figure 1.

Sequence Similarities between E. coli and Putative Arabidopsis Deformylases.

(A) Pairwise alignments of PurN and PurU from E. coli and At4g17360 and At5g47435. Amino acid residues important for enzyme activity in PurN are highlighted in black. PurN Asn-106, His-108, and Asp-144 are crucial for catalysis (*), while Ser-110 and His-137 are thought to be less important (*^#) (Almassy et al., 1992). The folate binding site includes Met-89, Ileu-91, Leu-118, and Leu-143 ($).

(B) The ACT domains of E. coli and Arabidopsis deformylases. The top row shows the consensus sequence of the ACT domain (Chipman and Shaanan, 2001). Small letters denote the following amino acid groups: b, big (FILMVWYKREQ); c, charged (DEHKR); h, hydrophobic (ACFILMVWY); l, branched (ILV); p, polar (DEHKNQRST); s, small (ACSTDNVGP). Conserved residues are highlighted in black.