4RWC

Racemic M2-TM crystallized from racemic detergent

Summary for 4RWC

• Entry DOI: 10.2210/pdb4rwc/pdb
• Related: 4RWB
• Descriptor: Matrix protein 2, octyl beta-D-glucopyranoside (3 entities in total)
• Functional Keywords: transmembrane peptide, proton channel, membrane, membrane protein
• Biological source: Influenza A virus
• Cellular location: Virion membrane : O70632
• Total number of polymer chains: 1
• Total formula weight: 3356.23

Authors

Mortenson, D.E.,Steinkruger, J.D.,Kreitler, D.F.,Gellman, S.H.,Forest, K.T. (deposition date: 2014-12-02, release date: 2015-10-14, Last modification date: 2020-07-29)

Primary citation

Mortenson, D.E.,Steinkruger, J.D.,Kreitler, D.F.,Perroni, D.V.,Sorenson, G.P.,Huang, L.,Mittal, R.,Yun, H.G.,Travis, B.R.,Mahanthappa, M.K.,Forest, K.T.,Gellman, S.H.
High-resolution structures of a heterochiral coiled coil.
Proc.Natl.Acad.Sci.USA, 112:13144-13149, 2015

PubMed Abstract: Interactions between polypeptide chains containing amino acid residues with opposite absolute configurations have long been a source of interest and speculation, but there is very little structural information for such heterochiral associations. The need to address this lacuna has grown in recent years because of increasing interest in the use of peptides generated from d amino acids (d peptides) as specific ligands for natural proteins, e.g., to inhibit deleterious protein-protein interactions. Coiled-coil interactions, between or among α-helices, represent the most common tertiary and quaternary packing motif in proteins. Heterochiral coiled-coil interactions were predicted over 50 years ago by Crick, and limited experimental data obtained in solution suggest that such interactions can indeed occur. To address the dearth of atomic-level structural characterization of heterochiral helix pairings, we report two independent crystal structures that elucidate coiled-coil packing between l- and d-peptide helices. Both structures resulted from racemic crystallization of a peptide corresponding to the transmembrane segment of the influenza M2 protein. Networks of canonical knobs-into-holes side-chain packing interactions are observed at each helical interface. However, the underlying patterns for these heterochiral coiled coils seem to deviate from the heptad sequence repeat that is characteristic of most homochiral analogs, with an apparent preference for a hendecad repeat pattern.

PubMed: 26460035
DOI: 10.1073/pnas.1507918112

Experimental method

X-RAY DIFFRACTION (1.05 Å)