Structure and mechanism of the influenza A M218–60 dimer of dimers - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of the American Chemical Society Année : 2015

Structure and mechanism of the influenza A M218–60 dimer of dimers

Résumé

We report a magic angle spinning (MAS) NMR structure of the drug-resistant S31N mutation of M218–60 from Influenza A. The protein was dispersed in diphytanoyl-sn-glycero-3-phosphocholine lipid bilayers, and the spectra and an extensive set of constraints indicate that M218–60 consists of a dimer of dimers. In particular, ∼280 structural constraints were obtained using dipole recoupling experiments that yielded well-resolved 13C–15N, 13C–13C, and 1H–15N 2D, 3D, and 4D MAS spectra, all of which show cross-peak doubling. Interhelical distances were measured using mixed 15N/13C labeling and with deuterated protein, MAS at ωr/2π = 60 kHz, ω0H/2π = 1000 MHz, and 1H detection of methyl–methyl contacts. The experiments reveal a compact structure consisting of a tetramer composed of four transmembrane helices, in which two opposing helices are displaced and rotated in the direction of the membrane normal relative to a four-fold symmetric arrangement, yielding a two-fold symmetric structure. Side chain conformations of the important gating and pH-sensing residues W41 and H37 are found to differ markedly from four-fold symmetry. The rmsd of the structure is 0.7 Å for backbone heavy atoms and 1.1 Å for all heavy atoms. This two-fold symmetric structure is different from all of the previous structures of M2, many of which were determined in detergent and/or with shorter constructs that are not fully active. The structure has implications for the mechanism of H+ transport since the distance between His and Trp residues on different helices is found to be short. The structure also exhibits two-fold symmetry in the vicinity of the binding site of adamantyl inhibitors, and steric constraints may explain the mechanism of the drug-resistant S31N mutation.

Dates et versions

hal-01363607 , version 1 (10-09-2016)

Identifiants

Citer

Loren B Andreas, Marcel Reese, Matthew T Eddy, Vladimir Gelev, Qing Zhe Ni, et al.. Structure and mechanism of the influenza A M218–60 dimer of dimers. Journal of the American Chemical Society, 2015, 137 (47), pp.14877-14886. ⟨10.1021/jacs.5b04802⟩. ⟨hal-01363607⟩
97 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More