Is a potent and selective inhibitor of alpha-1/beta-1 (ITGA1/ITGB1) integrin. It blocks the adhesion of alpha-1/beta-1-expressing K562 cells to immobilized collagens IV and I with IC(50) of 2 and 0.5 nM, respectively. Potently inhibits angiogenesis in chicken and in mouse model and reduces tumor development by half. Is 25-fold less potent than viperistatin. Monomer. Expressed by the venom gland. Does not show inhibitory activity toward alpha-2/beta-1 (ITGA2/ITGB1), alpha-IIb/beta-3 (ITGA2B/ITGB3), alpha-V/beta-3 (ITGAV/ITGB3), alpha-4/beta-1 (ITGA4/ITGB1), alpha-5/beta-1 (ITGA5/ITGB1), alpha-6/beta-1 (ITGA6/ITGB1), and alpha-9/beta-1 (ITGA9/ITGB1), alpha-4/beta-7 (ITGA4/ITGB7) integrins. Belongs to the disintegrin family. Short disintegrin subfamily.