Agitoxin-2 (AgTx2) from scorpion venom is a potent blocker of K+ channels. Researchers have now observed the binding dynamics of AgTx2 to the KcsA channel using high-speed atomic force microscopy. Single-molecule kinetic analyses revealed that the affinity of the channel for AgTx2 increased during persistent binding and decreased during persistent dissociation. The researchers propose a four-state model with relevant rate constants. An induced-fit pathway was dominant and accelerated binding by 400 times.
Click here for original story, Mechanism of scorpion toxin inhibition of K+ channel elucidated using high-speed AFM
Source: Phys.org