passages.id: split_8_test_1716_passage
passages.type: progene_text
passages.text: Surprisingly , neutralization of the gating charges at the outer end of the IIS4 segment by the mutations R850Q , R850C , R853Q , and R853C markedly enhances beta - scorpion toxin action , whereas mutations R856Q , K859Q , and K862Q have no effect .