Figure 6.

Schematic representation of mutations generated within the IglE N–terminus. Numbers 1–42 indicate the nucleotide triplet positioned with respect to the start codon of IglE. (A) Frameshift mutants FS1 to 4 covering the first 38 residues of IglE are shown. Residues altered via frameshift mutations are shaded in black, inserted nucleotides are boxed. To generate FS1, the nucleotide ‘T’ at position 4 was removed, which was compensated by the insertion of a ‘G’ immediately after the sixteenth nucleotide of IglE. To generate FS2, the nucleotide ‘C’ was inserted immediately after the eighteenth nucleotide of codon 6. This insertion was compensated by the removal of a ‘G’ at position 54 to restore the reading frame after codon 1718. FS3 was generated by omission of nucleotide 67 (an ‘A’) and insertion of ‘G’ after nucleotide 95 of codon 32. FS4 was generated by removal of nucleotide 97 (an ‘A’) followed by the insertion of ‘T’ after nucleotide 114 of codon 38. None of the Frameshift mutations overlapped with the lipidation site, LSSC, which is shaded in gray. All lipobox residues were individually substituted by alanine (see open triangles), while residues within the FS4 region were replaced individually or in pairs with the corresponding residues of the FS4 frameshift mutation (see filled triangles) (B) Frameshift mutants FS5 to 13 covering the first 6 residues of IglE are shown. Residues altered via frameshift mutations are shaded in black, inserted nucleotides are boxed. To generate mutant FS5, the nucleotide ‘T’ at position 4 was removed, which was compensated by the insertion of an ‘A’ immediately after the sixth eight nucleotide of IglE. To generate FS6, the nucleotide ‘T’ at position 4 was removed, which was compensated by the insertion of an ‘A’ immediately after the ninth tenth nucleotide. To generate FS7, the nucleotide ‘T’ at position 4 was removed, which was compensated by the insertion of a ‘T’ immediately after the twelfth thirteenth nucleotide. FS8, was generated by removing ‘T’ at position 4 and inserting ‘T’ after the fifteenth sixteenth nucleotide. FS9 was generated by removing ‘A’ at position 7 and inserting ‘T’ after the fifteenth sixteenth nucleotide. To generate FS10, ‘A’ at position 7 was removed and compensated by insertion of ‘G’ after the sixteenth nucleotide. To generate FS11, ‘A’ at position 10 was removed and compensated by insertion of ‘G’ after the sixteenth nucleotide. To generate FS12, ‘T’ at position 13 was removed and compensated by insertion of ‘G’ after the sixteenth nucleotide. To generate FS13, ‘T’ at position 16 was removed and exchanged to ‘G’.“