Fig. 4

IB formation of TrxA and MBP upon fusion to ssTorA. a E. coli TOP10F’ cells expressing the indicated TrxA constructs were lysed and subjected to differential centrifugation to separate the inclusion bodies (IB)-containing insoluble fraction from the soluble cell fraction (S). Samples of both fractions and corresponding whole cell (WC) samples were analyzed by SDS-PAGE and Coomassie staining. All samples were derived from the same amount of cell material. b Cells expressing indicated MBP constructs processed and analyzed as described under a. c Cells expressing indicated TrxA constructs carrying ssTorA sequence(s) at the C-terminus processed and analyzed as described under a. Full-length expression products (*), a processed product of ssTorA/TrxA (>) and lysozyme added during the fractionation procedure (Lys) are indicated. Molecular mass (kDa) markers are indicated at the left side of the panels. At the bottom of the panels the relative amount of overexpressed protein in the insoluble fraction compared to the whole cell lysates is displayed (% INS) as determined by densitometric quantification of the respective Coomassie stained bands. The following calculation was used: (density of protein band in lane IB/density of protein band in lane WC)*100%