Figure 1

A. Rate of synthesis of GroEL in E. coli MPh42 cells at different instants of growth in the presence of 50 μM CCCP. Pulse-label at 0, 5, 10, 15, 20, 30, 40 and 50 minutes of cell growth and subsequent immunoprecipitation experiment using anti-GroEL antibody was performed as described in 'Methods'. B. The level of sigma-32 in the CCCP-treated E. coli MPh42 cells. Log phase grown cells were divided into three parts. One part was grown at 30°C, one part was grown at 50°C and the other part was grown in the presence of 50 μM CCCP at 30°C. After 20 min of growth, 1 ml cell aliquot was withdrawn from each set. Cellular proteins were extracted by boiling the cells with SDBME buffer [18] and equal amount of protein from each extract, estimated by Bradford method [37], was electrophoresed on 12% SDS-polyacrylamide gel and subsequently the western blot study was performed using anti-sigma-32 antibody. Lane a: cells grown at 30°C; lane b: cells grown at 50°C and lane c: cells grown at 30°C in the presence of 50 μM CCCP.