FIG 3.

Procapsids generated from coat protein N-arm mutants have low or absent scaffolding protein incorporation at 16°C. (A) Analysis of protein profiles from a 5% (top) through 20% (bottom) sucrose gradient by 10% SDS-PAGE from cell lysates generated with WT and D14A, E15A, and E18A mutant coat proteins. Fractions are numbered at the bottom; positions of coat protein (c) and scaffolding protein (s) are indicated on the right. (B) Electron micrographs of the corresponding sucrose gradients (shown on the left). Fractions 16 and 22 usually correspond to procapsids and phage or aberrant morphologies, respectively.