{'fraction_non_alphanumeric': 0.023026315789473683, 'fraction_numerical': 0.004111842105263158, 'mean_word_length': 6.034682080924855, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Structural journey of an insecticidal pore-forming protein targeting western corn rootworm

Broad adoption of transgenic crops has revolutionized agriculture. However, resistance to insecticidal proteins by agricultural pests poses a continuous challenge to maintaining crop productivity and new proteins are urgently needed to replace existing transgenic traits. We identified an insecticidal membrane attack complex/perforin (MACPF) protein, Mpf2Ba1, with strong activity against western corn rootworm larvae and a novel site of action. By integrating X-ray crystallography, cryo-EM, and modelling, we determined monomeric, pre-pore and pore structures, revealing changes between structural states at atomic resolution. We discovered a monomer inhibition mechanism, a molecular “switch” associated with pre-pore activation/oligomerization upon gut fluid incubation and solved the highest resolution MACPF pore structure to-date. Our findings provide a mechanistic basis for Mpf2Ba1 effectiveness as an insecticidal protein with potential for biotechnology development. One-Sentence Summary The molecular mechanism of an insecticidal protein is revealed through 3D structures of the three main pore formation states