Figure 2

a) Sequence-structure alignment of ORFan R277 and the template mammalian polynucleotide kinase (PDB code: 1yj5, Chain: A). The ATP binding conserved motifs, Walker-A (P-loop) and Walker-B are highlighted in black with green and yellow backgrounds respectively. The conserved arginine motif in 1yj5 and R277 is shown in dark and light pink background respectively. b) Ribbon diagram of predicted model of ORFan R277. The model was generated from FFAS03 [55] and refined using Nest [53]. α-helices and β-strands are numbered numerically. The ATP-binding P-loop is highlighted in red color. The possible ATP interacting arginine residues (R103 and R107) present in the helical lid (helix α5) covering the P-loop are shown as sticks.