Table 2.

Drug susceptibilities of recombinant HCMVs expressing single and double mutations in the UL54 gene

UL54 genotypeIC50(μM)a
GCVCDVPFAADV
Wild type3.50.754542
F412C 15 (4.3) 13 (17)54 (1.2) 10 (−4.2)
L802M3.9 (1.1)0.7 (0.9) 140 (3.1) 120 (2.8)
F412C L802M 22 (6.2) 12 (16) 140 (3.1)25 (−1.7)
K513E 17.5 (5.0) 6.9 (9.2)50 (1.1)20 (−1.9)
D588E4.2 (1.2)0.8 (1.1) 110 (2.4) 84 (2.0)
K513E D558E 23 (6.6) 8.3 (11.1) 120 (2.7)33 (−1.3)
K805Q3.5 (1.0) 1.7 (2.2) 8.0 (−5.6) 8.9 (−4.8)
T821I 15.8 (4.5)1.4 (1.9) 950 (21) 260 (6.4)
K805Q T821I 15.1 (4.3) 1.6 (2.1) 455 (10.1) 170 (4.0)
  • a The IC50 values represent averages from at least three determinations with two independently generated recombinant viruses. In all cases, the standard error was less than 35%. The boldface numbers indicate a significant (i.e., at least twofold) change in HCMV drug susceptibility. Positive and negative numbers in parentheses represent fold increases and decreases, respectively, in the IC50 values of the mutant virus relative to that for the UL54 wild-type recombinant virus.