Changes in catalase proteins and activity in response to heat stress.

<p>(A) Catalase proteins in wild type (WT) and <i>chip, nbr1</i> double mutant collected at indicated hours (h) under heat stress. Total proteins (T), proteins from the first supernatants (S) and last pellets (P) were subjected to SDS-PAGES and probed with anti-catalase monoclonal antibody 3B6. Both a shorter (upper panel) and a longer (lower panel) exposure of the blot were shown so that the relative levels of both low and high molecular weight catalase proteins could be better visualized. (B) Catalase activity in wild type (WT) and <i>chip, nbr1</i> double mutant collected at indicated hours (h) under heat stress. Total proteins (T) and proteins from the first supernatants (S) were assayed for catalase activity using a spectrophotometric procedure. Error bars indicate SE (n = 3).