FIG. 2.

Amino acid sequences of proteases from TL-3 escape mutants resistant to TL-3 at passages (P) 21, 31, 37, 44, and 56. The fraction of clones containing non-wild-type R8 protease sequences is indicated in the rightmost column. The sequence of the R8 virus is shown in the top row. Identity with R8 at individual amino acid positions is indicated by dashes. Superscripts: a, not applicable (NA) since the PCR product was sequenced directly; b, position 53 was ambiguous at passage 56, but clonal analysis demonstrated two independent mutations to L (codons CTT and TTG).