Figure 1.

Schematic representation of the mechanistic principle of BN/SDS-PAGE for separation of protein complexes in snake venoms. (a)—Snake venoms contain protein complexes. In this example, four different protein complexes and one monomeric protein (pink in color) are shown. The red line between the baby blue, and the red protein indicates a disulfide bond. The snake venom is diluted in BN-PAGE sample buffer containing Ponceau S. (b)—This mixture is loaded into the wells of sample application gel, previously filled with B+Coomassie buffer. The Coomassie brilliant blue G-250 dye contained in this buffer binds onto the surfaces of protein complex, not allowing them to dissociate. (c)—Protein complexes (blue lines) migrate through the running gel, according to their molecular masses. (d)—Lanes are cut and incubated in SDS-PAGE running buffer, so that SDS binds to proteins, conferring tonto hem very similar charge-to-mass ratios. (e)—The lane and the filter paper containing the molecular mass markers are then inserted over the running gel, fixed with agarose, and electrophoresed. (f)—Except for protein complexes linked by disulfide bonds, the others disassemble and migrate vertically through the running gel, according to their molecular masses. The figure was partially created with biorender.com.