Proteome analysis of Escherichia coli periplasmic proteins in response to over-expression of recombinant human interferon α2b

Abstract

The periplasmic proteome of recombinant E. coli cells expressing human interferon-α2b (INF-α2b) was analysed by 2D-gel electrophoresis to find the most altered proteins. Of some unique up- and down-regulated proteins in the proteome, ten were identified by MS. The majority of the proteins belonged to the ABC transporter protein family. Other affected proteins were ones involved in the regulation of transcription such as DNA-binding response regulator, stress-related proteins and ecotin. Thus, the production of INF-α2b acts as a stress on the cells and results in the induction of various transporters and stress related proteins.

Forces Driving Chaperone Action

“…It appears that Spy binds to and releases client proteins in a regulated fashion that uses client protein folding as its own cue for release. The high density of positive charges on Spy’s client-binding site allows for a directed and very rapid binding of unfolded negatively proteins in the periplasm, and most periplasmic proteins are negatively charged (Heidary et al, 2014). After the initial encounter complex, hydrophobic interactions form between Spy and the unfolded client protein, which entropically stabilize the complex and result in a shielding of exposed hydrophobic surface on the client.…”