A robust fractionation method for protein subcellular localization studies in Escherichia coli.

Fractionation in Gram-negative bacteria is used to identify the subcellular localization of proteins, in particular the localization of exported recombinant proteins. The process of cell fractionation can be fraught with cross-contamination issues and often lacks supporting data for fraction purity. Here, we compare three periplasm extraction and two cell disruption techniques in different combinations to investigate which process gives uncontaminated compartments from Escherichia coli.