TABLE 3

C-terminal suppressors

Strain no. NCMSuppressorBackgroundTotal occurrencesDoubling timea (min)
4424R384Lfsb1150
4283E387 stopcDoubled fs3110
4443R185A110
447290
4277, 4295E388 stopcDouble4100
4355L394A100
4468R185A90
4285Q389 stopcDouble2110
4383L394A110
4365E390 stopcL394A2110
4462E121A110
4261, 4262eR391 stopcDouble9130f
4473E121A110
4464R122A130f
4358E392 stopcL394A1100
4275G393 (fs)cDouble1160g
4357E401 stopL394A190
4410E402 stophfs190
4281A403DDouble2100
4382L394A100
4474Y404NE121A190
4278Y404 stopDouble290
4471R185A90
  • a The doubling time of ΔC-terminal varied from 100 to 120 min in different experiments.

  • b “fs” refers to the frameshifted protein. See footnote e of Table 1.

  • c Suppressors that remove the original mutation.

  • d “Double” refers to G393A L394A.

  • e There are five additional strains with this genotype: 4263, 4264, 4280, 4288, and 4294.

  • f These longer doubling times may be due to a problem of charge balance because three of the four residues preceding R191 are E (Figure 3).

  • g Doubling time increased as ammonium decreased.

  • h Removal of three C-terminal residues from frameshifted protein.