FIG. 1.

Production of soluble recombinant variola virus B6 in baculovirus. (A) Diagram of full-length VV B5, recombinant protein B5t generated in a previous study (1), and the recombinant variola virus B6t generated in this study. Putative transmembrane regions (TM) are shown as dashed rectangles. The signal peptide of B5 is shown as a black rectangle. Consensus N-glycosylation sites are shown as black lollipops. Numbers refer to the residues at the beginning or end of the protein or the feature depicted within the protein (e.g., TM). Additional residues appended to the recombinant protein as a result of cloning are also shown, as well as a six-histidine tag (H6). (B) Sequence alignment of B5 (WR strain; primary accession number, Q01227) and variola virus B6 (Bangladesh-1975 strain; primary accession number, Q85402). The SCRs are underlined. Residues highlighted in gray are the 23 amino acids that differ between B5 and B6, 21 of which are located in the ectodomain. Black boxes indicate putative N-glycosylation sites. The start of the transmembrane domain (TM) and cytoplasmic tail (CT) are indicated. The alignment was made using ClustalW (24).