Dynamics and Rigidity of an Intact Filamentous Bacteriophage Virus Probed by Magic Angle Spinning NMR.

The capsid dynamics of filamentous bacteriophages is related to their function, stability, and interactions with the genome, and can be assessed by measuring the chemical shift anisotropy (CSA) of 15 N amides, which are sensitive to large amplitude motions. In this study, CSA recoupling experiments under magic-angle spinning NMR were used to probe the dynamics of the y21m capsid mutant of fd bacteriophage. Based on fitting the generated CSA lineshapes, residues located in the N-terminus undergo increased motional amplitudes suggesting its global motion, whereas other backbone residues are rigid, and imply a tight hydrophobic packing of the phage.