Fig. 5. (A) Cpc1 sequences predicted to fold into an EF hand, with residues important for coordination of Ca²⁺ underlined. (B) Alignment of portions of the Cpc1 adenylate kinase domain with the complete sequence of human adenylate kinase isoform 2 (AAC52061). Identical residues are shaded black, conservative replacements in grey. Cpc1 sequences homologous to adenylate kinase are separated into four segments, with segment 1 spanning the phosphate binding loop (P-loop, Walker A motif) and segment 3 encompassing the highly conserved Walker B motif. Arrows (segments 1 and 4) indicate arginine residues that may be important for substrate interactions. The RxxH sequence in segment 4, part of the LID domain, is common to most eukaryotic adenylate kinases.