TABLE 1

Intragenic suppressors upstream of the C terminus

Strain no. NCMamtB mutationsSuppressors
4193G393A L394A (double; inactive)2 strains, A179E
4238L394A (inactive)16 strains in 9 positions
4275Frameshift (slightly active)a19 strains in 14 positions
4350Loop mutationb1 strain, V116L
Total38 strains in 20 positionsc
  • a fs lesion: the protein sequence of the wild-type C terminus, beginning with residue 381, is VGLRVPEEQEREGLDVNSHGENAYNA; the protein sequence of the frameshift C terminus is VGLRVPEEQERESGGCQQPRRECL. The fs was obtained as a suppressor of the double.

  • b The only suppressor mutation was obtained in K255A, which lies in loop 7.

  • c The total number of suppressors examined was 116, of which 68 were intragenic (Inwood et al. 2009).