Quasispecies analysis of FU-treated LCMV populations.

aBHK-21 cell monolayers were infected at the indicated MOI in the absence or presence of 5-fluorouracil, as detailed in Materials and Methods.bThe genomic regions sequenced were the entire Z-coding region and residues 3654 to 4260 of the L-coding region.cTiter of LCMV progeny determined at 48 h p.i.dQuantification by real time RT-PCR of LCMV RNA in progeny, extracellular virus at 48 h p.i. in molecules/ml.eRatio of virus titer and number of viral RNA molecules per ml of cell culture supernatant determined at 48 h p.i.fAverage number of mutations per nucleotide, counted relative to the corresponding consensus nucleotide sequence.gProportion of different genomic sequences in the mutant spectrum of the quasispecies, calculated as described in Materials and Methods.hThe omitted transversion types were not represented in the sequences analyzed.