TABLE 2

G4 nucleotide substitutions observed after 50 passages of selection at 41.5°

MutationGeneAA changeFirst detectedFinal statusa
247 C → TA63Silent6Fixed
3665 C → TF355P → S6Fixed
4988 G → AH142G → D12Polymorphicc
720 C → TA221/A*8T → I18Fixed
4703 C → TH47A → V33Polymorphicc
4967 G → AbH135G → D15Polymorphicd
1269 A → GbA404/A*191N → S42Polymorphice
153 C → TbA32S → F50Polymorphic
  • a These results are based on sequences and oligo probing. The “Final status” classification is based on probing and on sequences of three isolates at G450 before initiating the 44° selection.

  • b Mutations not present in the isolate used to initiate the 44° selection. After an additional 20 passages at 41.5° (beyond passage 50), the indicated sites were fixed, lost, or remained polymorphic (footnotes c, d, and e). Mutation 153T was not detected in the consensus sequence from passage 70 but was never probed for; mutation 125G was present at 80%.

  • c Fixed at passage 70.

  • d Lost at passage 70.

  • e Remained polymorphic at passage 70.