FIG. 3.

Hsp31 overexpression alleviates protein misfolding in cells subjected to aggravated oxidative stress and acid stress. ΔhchA cells harboring either the cloning vector ptetA3 (− lanes) or the Hsp31 expression vector pMM114 (+ lanes) were grown at 37°C in LB-chloramphenicol medium supplemented with 0.05 μg/ml anhydrotetracycline. Cultures were subjected to oxidative stress at 45°C (A) or to acid shock at 37°C (B). Insoluble cell fractions were collected 1 h after imposition of stress. Arrows and braces show the migration positions of proteins that are present at lower levels in the insoluble fraction of Hsp31-overexpressing cells. The panels on the right show the results of a videodensitometric analysis of the gel lanes. Gray lines correspond to the insoluble fraction of Hsp31-overexpressing cells, while black lines correspond to the insoluble fraction of cultures harboring the ptetA3 vector.