Figure 1.

Growth medium conditions that extend chronological life span. (A) Relative to growth in SC 2%, reducing the glucose present in the medium, use of glycerol as the carbon source, transfer to water, or addition of sorbitol increases cell survival. On the indicated days, the aging culture was serially diluted ten-fold in rich YPD medium, and 5 ul of each dilution was spotted onto YPD agar plates and incubated for 48 hours at 30°C. A single representative biological experiment for each condition is depicted; triplicate biological replicates were performed. SC 2%, SC 0.5% and SC 0.05% = synthetic complete medium at the indicated glucose concentration; SG 3% = synthetic complete 3% glycerol; SC 2% H₂O Txfr = SC 2% cells washed and transferred to distilled water at day 2; SC 2% + 18% sorbitol = SC 2% supplemented with 18% sorbitol. (B) Glucose is depleted in logarithmically growing cultures. The diploid strain BY4743 was grown overnight in YPD, and back-diluted 1:100 (starting density = ∼1.4 × 10⁶ cells/ml) in SC 2% or SC 0.05% medium. Error bars are standard deviation of biological duplicates.