<p><b>Aligned Middle American Rattlesnake (<i>Crotalus simus tzabcan</i>) C-type lectins (A) and serine proteases (B).</b> A) Four unique venom-based C-type lectin transcripts (asterisks) were identified for <i>C</i>. <i>s</i>. <i>tzabcan</i> and aligned to other crotaline species. Identical nucleotide sequences are shaded and corresponding GenBank accession numbers are as follows: Crotalus_adamanteus (AEJ31974.1), Deinagkistrodon_acutus (AAM22790.1), Crotalus_d_terrificus (Q719L8.1), and Crotalus_o_helleri (AEU60004.1). B) Venom-based serine proteases cDNA sequences (asterisks) were also obtained from <i>C</i>. <i>s</i>. <i>tzabcan</i> and were aligned with toxins from several other species; identical nucleotide sequences are shaded, and the catalytic triad composed of Ser195, Asp102, and His57 associated with thrombin-like activity in snake venom serine proteases are identified (arrowheads). Isoform 3 from <i>C</i>. <i>s</i>. <i>tzabcan</i> is a partial sequence. GenBank accession numbers are as follows: Agkistrodon_p_leucostoma (HQ270466.1), Bothrops_asper (DQ247724.1), Crotalus_d_terrificus7 (EU360954.1), Crotalus_d_terrificus4 (EU360952.1), Crotalus_d_terrificus3 (EU360951.1), Crotalus_d_durissus (DQ164401.1), Sistrurus_c_edwardsi (DQ464239.1), Trimeresurus_mucrosquamatus (X83225.1), Crotalus_adamanteus (HQ414118.1), Calloselasma_rhodostoma (L07308.1), Deinagkistrodon_acutus (AY861382.1), Trimeresurus_stejnegeri (AF545575.1), and Crotalus_atrox (AF227153.1).</p