Fig. 2

Reverse phase HPLC chromatograms showing a “northern” venom phenotype from Montana (a) and a “southern” venom phenotype from Texas (b). Note the size differences between the 22-min myotoxin peak and the 85-min SVMP peaks. c Principal component analysis with 95% confidence intervals of shotgun proteomics log-transformed protein spectral intensity data with proteins binned by protein family (n = 8). d Heatmap of log-transformed protein spectral intensities using Euclidean distance measures and Ward’s clustering method showing significantly different protein abundances (*) based on unpaired T-test (p < 0.05; n = 8). Red = northern phenotype, green = southern phenotype. L-AAO = L-amino acid oxidase, Hyal = hyaluronidase, PDE = phosphodiesterase, CRiSPs = cysteine rich secretory proteins, Thr SVSP = thrombin-like snake venom serine protease, BPP = bradykinin potentiating peptides, PLA2 = phospholipase A₂, SVSP = snake venom serine protease, VNGF = venom nerve growth factor, VF = venom factor, PLB = phospholipase B, CTL = c-type lectin, SVMP = snake venom metalloprotease, VEGF = vascular endothelial growth factor, Kall-SVSP = kallikrein-like snake venom serine protease