Figure 4

Denaturation of MS2 VLPs. (A) Coincidence of VLP disassembly, as determined by loss of the VLP band on an agarose gel, and coat protein denaturation, determined by disappearance of soluble protein as a function of temperature. "MS2 WT" denotes the wild-type coat protein, while "MS2 sc-dimer" refers to the MS2 coat protein single-chain dimer. "Soluble" indicates whether the data points were obtained by measuring the amount of soluble protein remaining after treatment and "VLP" identifies data points showing the quantity of intact VLP. (B) Denaturation of various recombinant VLPs as a function of temperature. "F13/14" and "F13/16" refer to VLPs displaying the Flag epitope at two different locations in the AB-loop (see the text). "ECL2" and "V3" refer to VLPs displaying the extracellular loop 2 of CCR5 and the V3 loop of the HIV envelope protein, respectively. "Random 10mer" identifies results obtained using a complex library of random-sequence 10mer insertions. (C) Denaturation of the indicated MS2 VLPs as a function of time at 55°C.