Localization of BiP to translating ribosomes increases soluble accumulation of secreted eukaryotic proteins in an Escherichia coli cell‐free system

The endoplasmic reticulum (ER) resident Hsp70 chaperone, BiP, docks to the Sec translocon and interacts co‐translationally with polypeptides entering the ER to encourage proper folding. In order to recreate this interaction in Escherichia coli cell‐free protein synthesis (CFPS) reactions, a fusion protein was formed between the ribosome‐binding portion of the E. coli protein trigger factor (TF) and BiP. The biophysical affinity to ribosomes as...