Fig 2.
Eight nsp1 sequences from α-CoV and four nsp1 sequences from β-CoVB were aligned separately. The two alignments were subsequently merged by using the three-dimensional structure alignment of TGEV nsp1 and SARS-CoV nsp113–128. The level of sequence conservation within each genus is highlighted with dark background color and white letters. A darker background color indicates a higher level of conservation. Residues conserved between the genera are marked with boxes. Residues likely to be important for α-CoV function are marked by stars. These residues are further highlighted in Fig. 3 and 4. The β-CoVB consensus sequence suggested by Almeida et al. (28) is marked by circles. Secondary structure elements from the TGEV nsp1 structure are displayed above the sequence and colored according to the scheme in Fig. 1. The figure was prepared using the software program Aline (47).