2KSJ

Structure and Dynamics of the Membrane-bound form of Pf1 Coat Protein: Implications for Structural Rearrangement During Virus Assembly

Summary for 2KSJ

• Entry DOI: 10.2210/pdb2ksj/pdb
• Descriptor: Capsid protein G8P (1 entity in total)
• Functional Keywords: membrane protein, capsid protein, host membrane, membrane, transmembrane, virion, viral protein
• Biological source: Pseudomonas phage Pf1 (Bacteriophage Pf1)
• Cellular location: Virion (Potential): P03621
• Total number of polymer chains: 1
• Total formula weight: 4612.39

Authors

Park, S.,Marassi, F.,Black, D.,Opella, S.J. (deposition date: 2010-01-05, release date: 2010-11-10, Last modification date: 2024-05-01)

Primary citation

Park, S.H.,Marassi, F.M.,Black, D.,Opella, S.J.
Structure and dynamics of the membrane-bound form of Pf1 coat protein: implications of structural rearrangement for virus assembly.
Biophys.J., 99:1465-1474, 2010

PubMed Abstract: The three-dimensional structure of the membrane-bound form of the major coat protein of Pf1 bacteriophage was determined in phospholipid bilayers using orientation restraints derived from both solid-state and solution NMR experiments. In contrast to previous structures determined solely in detergent micelles, the structure in bilayers contains information about the spatial arrangement of the protein within the membrane, and thus provides insights to the bacteriophage assembly process from membrane-inserted to bacteriophage-associated protein. Comparisons between the membrane-bound form of the coat protein and the previously determined structural form found in filamentous bacteriophage particles demonstrate that it undergoes a significant structural rearrangement during the membrane-mediated virus assembly process. The rotation of the transmembrane helix (Q16-A46) around its long axis changes dramatically (by 160 degrees) to obtain the proper alignment for packing in the virus particles. Furthermore, the N-terminal amphipathic helix (V2-G17) tilts away from the membrane surface and becomes parallel with the transmembrane helix to form one nearly continuous long helix. The spectra obtained in glass-aligned planar lipid bilayers, magnetically aligned lipid bilayers (bicelles), and isotropic lipid bicelles reflect the effects of backbone motions and enable the backbone dynamics of the N-terminal helix to be characterized. Only resonances from the mobile N-terminal helix and the C-terminus (A46) are observed in the solution NMR spectra of the protein in isotropic q > 1 bicelles, whereas only resonances from the immobile transmembrane helix are observed in the solid-state (1)H/(15)N-separated local field spectra in magnetically aligned bicelles. The N-terminal helix and the hinge that connects it to the transmembrane helix are significantly more dynamic than the rest of the protein, thus facilitating structural rearrangement during bacteriophage assembly.

PubMed: 20816058
DOI: 10.1016/j.bpj.2010.06.009

Experimental method

SOLID-STATE NMR
SOLUTION NMR