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Updated: Aug 1, 2026

Expression, Detergent Solubilization, and Purification of a Membrane Transporter, the MexB Multidrug Resistance Protein
Published on: December 3, 2010
Transport and cleavage of bacterial pre-beta-lactamase by mammalian microsomes
Abstract:
Eucaryotic endoplasmic reticulum and bacterial inner cell membranes use strikingly similar mechanisms to transport proteins from one cellular compartment to another. Using a mammalian linked transcription-translation system, we show here that canine pancreatic microsomes accurately cleave off the signal sequence of beta-lactamase, a secreted bacterial protein. We suggest that the apparent differences between bacterial and eukaryotic protein transport may involve only minor modulations of a profoundly conserved mechanism.
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