Figure 2.

Mutation spectra of Y265C and β-WT. (A) β-WT. (B) Y265C. The sequence of the λ cII gene is shown. All base-substitution mutations and one-base-pair frameshift mutations are shown in the spectra. Base substitutions are above the cII sequence; single base deletions (▵) and single base insertions (▴) are below the sequence at the site at which they were observed. The circled G → A and single base-insertion mutations were present in one cII mutant. These mutations are considered as separate events because they are greater than 15 bases apart (13). Not included in the Y265C spectrum are the deletions occurring between 140–154, 242–244, 226–236, and 230–248; these are shown in Fig. 3. Not included in the β-WT spectrum is the deletion of AA at position 60–61.