FIG. 5.

Role of disulfide bonds in the stability of the SDS-sensitive YscC oligomer. Purified YscC oligomer was incubated in the absence (−) or presence (+) of 20 mM DTT for 10 min at 40°C and was either dissociated into monomers by treatment with TCA and TFA and loaded on a 8% polyacrylamide gel (A) or directly loaded on a seminative 3 to 9% polyacrylamide gradient gel (B). The positions of the reduced and oxidized forms of the YscC monomer and the native and nonnative forms of the YscC oligomer are indicated to the right of the gels. Proteins were visualized by staining with silver.