Figure 3.

Electron micrographs of recombinant B/Perth D NA heads. Samples were negatively stained with uranyl acetate and show two-dimensional arrays of NA heads: (A) simple square tessellation; (B) “hound’s-tooth” pattern of orthogonal rows and columns but with the square NA heads rotated through 45°; (C) an open square lattice with NA heads oriented on their sides or edges. Scale bars, 50 nm.