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Insect resistance to insecticides is an increasingly serious problem, and the resistant mechanisms are complicated. The resistance research based on the chemosensory pathway is one of the hot problems at present, but the specific binding mechanism of chemosensory genes and insecticides remains elusive. The binding mechanism of AlepGOBP2 (belong to insect chemosensory gene) with two insecticides was investigated by computational and experimental approaches. Our calculation results indicated that four key residues (Phe12, Ile52, Ile94, and Phe118) could steadily interact with these two insecticides and be assigned as hotspot sites responsible for their binding affinities. The significant alkyl−π and hydrophobic interactions involved by these four hotspot residues were found to be the driving forces for their binding affinities, especially for two residues (Phe12 and Ile94) that significantly contribute to the binding of chlorpyrifos, which were also validated by our binding assay results. Furthermore, we also found that the AlepGOBP2–chlorpyrifos/phoxim complexes can be more efficiently converged in the residue-specific force field-(RSFF2C) and its higher accuracy and repeatability in protein dynamics simulation, per-residue free energy decomposition, and computational alanine scanning calculations have also been achieved in this paper. These findings provided useful insights for efficient and reliable calculation of the binding mechanism of relevant AlepGOBPs with other insecticides, facilitating to develop new and efficient insecticides targeting the key sites of AlepGOBP2.

We calculate the complete form of the dimension-8 condensate contributions in the two-point correlator of the (1−+,0++) light hybrid current considering the operator mixing under renormalization. We find the inclusion these higher power corrections as well as the update of 〈g3G3〉increase the QCD sum rule mass prediction for the 1−+light hybrid. The obtained conservative mass range 1.72–2.60 GeV does not favor the π1(1400)and the π1(1600)to be pure hybrid states and suggests the π1(2015)observed by E852 is more likely to have much of a hybrid constituent. We also study the b1πand ρπdecay patterns of the 1−+light hybrid with light-cone QCD sum rules. We obtain a relatively large partial decay width of the b1πmode, which is consistent with the predictions from the flux tube models and lattice QCD. More interestingly, using the tensor interpolating current we find the partial decay width of the ρπmode is very small due to the lack of the leading twist contribution in the light-cone expansion of the correlation function.

Some pentapeptides with higher alpha-helical tendency possess typical sequence pattern, such as “ - - - ”, “ - - - - ”, “ - - - - ”, and “- - - - ” (“” D,N,E,Q,K,R,T,C, or H; “-” L,I,V, or A), especially symmetrical motifs (a pair of reverse sequences beside palindromic segments), such as ALALA, QQAQE/EQAQQ, and REALE/ELAER, hint that the nascent peptide can fold a certain conformation in a two-way folding fashion.