SecB, a remarkable chaperone involved in protein export, binds diverse ligands rapidly with high affinity and low specificity. It plays a crucial role during protein export via the general secretory pathway by modulating the partitioning of precursors between folding or aggregation and delivery to the membrane-bound translocation apparatus. SecB has the potential to participate in functions outside of export acting as a general nonspecific chaperone to provide buffering capacity of the nonnative state of proteins in the cytosolic pool. Recombinant E. coli SecB protein was expressed in E. coli and purified by using conventional chromatography. Alternative Names: SecB protein, Protein export protein secB, Protein export chaperone protein