Table 3

Fitness in mice and in LB of SmR and compensated mutants.

StrainMutationCompensation selection conditionRelative fitness in miceRelative fitness in LB
S4*S12*
JB124wtwtNA1.01.0
JB127wtK42N (AAC)NA0.500.79
JB2162Q53LwtNA0.620.68
TH5461Q53LK42NLB1.00.93
TH5664K205NK42NLB0.940.81
TH5604Q53PK42NLB0.910.96
TH5606V200K42NLB0.910.90
TH5516I199NK42NLB0.910.90
TH5667UAG201K42NLB0.910.84
JB1258wtK42R (AGA)Mice1.00.96
  • * Amino acid changes in ribosomal proteins S4 and S12 (11). The nucleotide sequence of codon 42 is shown in parentheses.

  • Growth condition under which the compensated mutants were selected (7).

  • The relative fitness is defined as the generation time of the wild type divided by the generation time of the mutant (19). wt, wild type; NA, not applicable.