Skip to main content
. Author manuscript; available in PMC: 2015 Mar 20.
Published in final edited form as: J Mol Biol. 2013 Nov 2;426(6):1220–1245. doi: 10.1016/j.jmb.2013.10.033

Figure 3. Structural comparison of APOBEC family members' crystal structures.

Figure 3

(A) The APOBEC proteins have a canonical deaminase core composed of five β strands and six α helices. As a prototype, the wild-type A3G-CTD monomer structure (PDB entry 3IQS) with the indicated α-helices, β-strands and loops is shown in a ribbon representation. Loop 3, 5, and 7 (L3, L5, and L7, respectively) are shown in blue, orange, and magenta colors, respectively. (B) The active site of A3G-CTD. A zinc atom is coordinated by the three residues H257, C288 and C291, and indirectly via a water molecule (view occluded by zinc atom) with E259. (C) Comparison of ribbon representations of A2 (PDB entry 2NYT), A3A (PDB entry 2M65), A3C (PDB entry 3VOW), A3F-CTD (PDB entry 4IOU), A3G-CTD (PDB entry 3ISQ) and A3G-CTD-2K3A (PDB entry 3IR2) crystal structures. The β1/β2 region is highlighted (blue oval) to emphasize similarities and the conformational plasticity in the β1-β2 loop region across all A3 proteins. The α1 helix (red box) exhibits a similar orientation across all A3 proteins but differs in A2 crystal structure. The corresponding loops (L3, L5, and L7) in Fig. 3A are also labeled in A3A and A3G structures.