Figure 4.

Long-lived strains are resistant to lethal heat-stress or oxidative insult. (A) Mid-log cells were treated with a 2-min, 55°C heat shock, and survival was calculated relative to untreated isogenic strains. The mep2Δ and gln3Δ strains were significantly protected compared with the parental strain (P < 0.0159 for mep2Δ and P < 0.0001 for gln3Δ). (B) Mid-log cells were inoculated into media containing 1 mM of the free-radical-generating drug paraquat, and growth was compared with untreated isogenic strains after 15 h. Deletion of MEP2 or GLN3 affords significant protection from paraquat (P = 0.002 for mep2Δ and P < 0.0001 for gln3Δ). For all groups, n = 6, and bars are mean ± SEM.