Figure 5.—

An increase in minisatellite tract alteration takes place after a growth arrest in the Δzrt1 strain. (Top) Wild-type (WT) vs. Δzrt1 growth curves. The zrt1 null strain DTK878 and its parent DTK271 were grown in rich liquid media at 30° for 132 hr. The OD₆₀₀ was measured (circles for DTK271, squares for DTK878) every 12 hr. Data represent an average of three independent experiments. (Bottom) Frequency of white CFUs in WT vs. Δzrt1. Cultures from the growth curves (top) were diluted and plated every 12 hr as described above. Data shown represent an average of three independent experiments. Chi-squared analysis showed a significant difference between the percentage of white CFUs in the zrt1 deletion strain (solid bars) and the wild-type parental strain (striped bars) for all time points from 48 hr on (P < 0.01).