TABLE 2.

Plaque sizes, burst sizes, and DNA copies per PFU synthesized by UL42 mutants

VirusPlaque sizea [mm2] (P value)Burst size, [PFU/cell]b (P value)Virus yieldc [105 PFU/ml] (P value)Virion DNA copies/PFUd (P value)
C700-A1.1 ± 0.0930 ± 0.819 ± 2.8100 ± 10
C700-B1.1 ± 0.1026 ± 2.6NDeND
Q282R-A1.0 ± 0.0919 ± 1.78.6 ± 3.0230 ± 60
Q282R-B1.0 ± 0.09 (<0.01)23 ± 1.8 (<0.05)9.0 ± 3.8 (<0.01)320 ± 80 (<0.05)
D270A/D271A-A0.93 ± 0.1020 ± 2.811 ± 2.5170 ± 2
D270A/D271A-B0.94 ± 0.10 (<0.01)20 ± 0.0 (<0.05)12 ± 0.7 (<0.05)170 ± 20 (>0.05)
Q282R/D270A/D271A-A0.92 ± 0.0919 ± 2.77.1 ± 1.5400 ± 50
Q282R/D270A/D271A-B0.91 ± 0.07 (<0.01)18 ± 0.0 (<0.05)7.2 ± 4.2 (<0.01)400 ± 10 (<0.05)
  • a Plaque size is expressed as average and standard deviation for 20 plaques at 72 h postinfection. Student's t test was used to calculate the P value of the statistical significance of the differences between the mutant (both A and B) and the control viruses (C700-A and C700-B) expressing wild type UL42.

  • b Burst size was calculated by the ratio of peak titer (36 h postinfection) of the single growth curve assay over the number of cells. Data are averages and standard errors for two experiments. An ANOVA test was applied to calculate the P value.

  • c Virus yield was the peak titer of progeny virus harvested at 72 h after infection with an MOI of 0.01. Data are averages and standard errors for two experiments. An ANOVA test was applied to calculate the P value.

  • d Virion DNA copies/PFU and standard errors were calculated by determining the ratio of numbers of DNA copies present in cell-free medium over viral titers at 72 h postinfection with the inoculation of an MOI of 0.01. An ANOVA test was applied to calculate the P value.

  • e ND, not determined.