Quasispecies analysis of FU-treated VSV, FMDV and EMCV populations.

a<p>BHK-21 cell monolayers were infected with VSV, FMDV or EMCV at the indicated MOI in the absence or presence of 5-fluorouracil, as detailed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032550#s4" target="_blank">Materials and Methods</a>.</p>b<p>The genomic regions sequenced were nucleotides 5902 to 6569 of the L-coding region of VSV, 6800 to 7350 of the 3D (polymerase)-coding region of FMDV, and 6718 to 7403 pf the 3D (polymerase)-coding region of EMCV.</p>c<p>Titer of VSV, FMDV and EMCV progeny determined at 24 h p.i.</p>d<p>Average number of mutations per nucleotide, counted relative to the corresponding consensus nucleotide sequence. The mutation frequency of VSV increased in the presence of FU, and was 1.9-fold higher at low than at high MOI, but the differences were not statistically significant (p = 0.33; χ² test).</p>e<p>Proportion of different genomic sequences in the mutant spectrum of the quasispecies, calculated as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032550#s4" target="_blank">Materials and Methods</a>. Variations in Shannon entropy followed, the same trend as variations in mutation frequency but, again, the differences were not statistically significant (see footnote d).</p>f<p>The omitted transversion types were not represented in the sequences analyzed.