Figure 3.

Karyotype analysis confirms partial or complete loss of chromosomes. (A) Contour‐clamped homogeneous electric field (CHEF) gel showing the size and number of chromosomes for strains which have lost chromosome 14 (14‐1, 14‐3, 14‐5 and 14‐6) or a region of chromosome 14 (14‐2, 14‐4 and 14‐7). Chromosome 13 is indicated with an arrowhead for reference. All strains lack the smallest chromosome from the wild‐type (WT) strain (chromosome 15) as well as the normal sized chromosome 14. Strains 14‐2, 14‐4 and 14‐7 have a smaller chromosome absent in the WT strain, indicated with arrows. (B) CHEF gel analysis of strains with partial or complete loss of chromosome 12 (labelled 12‐1–12‐8). Chromosomes 11 and 12, which run closely together, are indicated with an arrowhead. In all the selected strains without GFP (green fluorescent protein gene), the band corresponding to chromosome 12 is missing. Below chromosome 11 in these strains are chromosomes 13–15, in most cases followed by a novel chromosome. This presumed remainder of chromosome 12 is indicated with an arrow in 12‐1. This chromosome is absent in 12‐5, suggesting the complete loss of chromosome 12 in this strain.