Structure of the coat protein in Pf1 bacteriophage determined by solid-state NMR spectroscopy.
The atomic resolution structure of Pf1 coat protein determined by solid-state NMR spectroscopy of magnetically aligned filamentous bacteriophage particles in solution is compared to the structures previously determined by X-ray fiber and neutron diffraction, the structure of its membrane-bound form, and the structure of fd coat protein. These structural comparisons provide insights into several biological properties, differences between class I and class II filamentous bacteriophages, and the assembly process. The six N-terminal amino acid residues adopt an unusual "double hook" conformation on the outside of the bacteriophage particle. The solid-state NMR results indicate that at 30 degrees C, some of the coat protein subunits assume a single, fully structured conformation, and some have a few mobile residues that provide a break between two helical segments, in agreement with structural models from X-ray fiber and neutron diffraction, respectively. The atomic resolution structure determined by solid-state NMR for residues 7-14 and 18-46, which excludes the N-terminal double hook and the break between the helical segments, but encompasses more than 80% of the backbone including the distinct kink at residue 29, agrees with that determined by X-ray fiber diffraction with an RMSD value of 2.0 A. The symmetry and distance constraints determined by X-ray fiber and neutron diffraction enable the construction of an accurate model of the bacteriophage particle from the coordinates of the coat protein monomers.
Thiriot
David S
DS
Department of Chemistry and Biochemistry, University of California, San Diego, CA 92093-0307, USA.
Nevzorov
Alexander A
AA
Zagyanskiy
Lena
L
Wu
Chin H
CH
Opella
Stanley J
SJ
D025561:Bacteriophage Pf1 / Q000378:metabolism*; D001435:Bacteriophages / Q000378:metabolism; D036022:Capsid Proteins / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009502:Neutrons; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D012984:Software; D013223:Statistics as Topic; D013696:Temperature; D014961:X-Ray Diffraction; D014965:X-Rays
D036022:Capsid Proteins; C071283:coat protein, Pseudomonas phage Pf1