Fig. 1From: Adaptive evolution in the toxicity of a spider’s venom enzymesPartial multiple alignment of amino acid sequences of SMase D. In this analysis, sites Cys96 and Cys102 correspond to Cys51 and Cys57, respectively, and form a disulphide bridge in Class I and Class II isoforms. The sites Cys98 and Cys264 (corresponding to Cys53 and Cys201) form an additional bridge in SMase D Class II membersBack to article page