For the numbering above, the A3A amino acid sequences were extracted from the corresponding pdb files (4xxo and 5sww). The other A3 enzyme sequences were from their pdb files as shown in Table : A3B (5cqd),A3C (3vm8), A3D (alphafold modeled from the q96ak3 Uniprot sequence after removal of the first 200 amino acids), A3F (5hx5),A3G (3v4k),A3H (6b0b) and AID (5w0z). Activationinduced cytidine deaminase (AID) participates in antibody diversification by class switch recombination and somatic hypermutation. The human AID enzyme is very similar to other APOBEC3 enzymes. AID has been included in this work because of its importance on antibody response. Clone Manager was employed for the alignements using CLUSTAL W (1.7).*, conserved amino acids.---, alignements gaps. XXX, amino acids nearby 4 Å of the dAdTdCdGdGdG ssDNA oligomer merged from A3A 5sww.pdb. Red rectangles, conserved Cysteins. Green rectangles, highly conserved amino acids around Cysteins or ssDNA.