FIGURE 3.

Mutated Cosmc has little effect on restoration of denatured T-synthase activity. A, depiction of the 6×His-sCosmc and 6×His-msCosmc constructs, where the latter has a point mutation E152K. B, SDS-PAGE analysis of purified recombinant soluble human 6×His-sCosmc and 6×His-msCosmc, as indicated. Lane 1, molecular weight standards; lane 2, 6×His-msCosmc (∼8 μg); lane 3, human N-terminal 6×His-sCosmc (∼4 μg). A densitometry scan of the protein bands in lanes 2 and 3 showed that the amount of protein corresponding to the apparent molecular mass of ∼35 kDa for both 6×His-smCosmc and 6×His-sCosmc were similar. C, renaturation of heat-denatured HPC4-sT-syn (DT-syn) was initiated by addition of 6×His-msCosmc and with recombinant 6×His-sCosmc, and percent T-synthase activity was determined. In C, each assay was performed in duplicate, three replicate experiments were performed, and data represent the average of all experiments. Error bars, ± 1 S.D. from the average. The vertical line separates experiments done at two different time points.