Overproduction of membrane proteins in the E. coli strains generally induce cell death. The multiple mutant C43 (DE3) derivative of BL21 (DE3) strain was selected to resist this overproduction. In this mutant, the membrane protein of interest continues to be overproduced without cell death or even stop growing, but, more, the cells accumulate, after a few hours of growth, intracellular membrane system, not connected to the plasma membrane of the cell, wherein the overexpressed membrane protein is inserted. This phenomenon of cell proliferation, described for the first time in the bacterium Escherichia coli, evokes, at least from the cytological point of view, the structures observed in the mitochondria.
Project in collaboration with Bruno Miroux and Marc Uzan,
UMR7099. Laboratoire de Physico-Chimie Moléculaire des Membranes Biologiques
Institut de Biologie Physico-chimique
13 rue Pierre et Marie Curie. 75005. Paris