title: Forceful large-scale expression of "problematic" membrane proteins.
abstract: We developed an Escherichia coli expression system for overproduction of a highly toxic membrane protein that is impossible to overexpress by traditionally used approaches. The method is based on combination of the genetic modifications of a bicistronic expression plasmid, stabilization of a synthesized protein, and selection of a compatible expression host. This enabled us to enhance the expression level of a toxic membrane protein 30-50 times compared with expression in the native state and to obtain 3-5mg of a highly purified functionally active protein per liter of culture. We describe the method for the amplified expression of membrane proteins, using the Pseudomonas aeruginosa multidrug resistance protein, MexY, as an example. The amplified MexY was correctly folded in the cytoplasmic membrane of the E. coli without forming inclusion bodies. This method can be applicable to the large-scale expression of the other problematic membrane proteins that are otherwise extremely difficult to overproduce.
authors.affiliation: Department of Molecular Life Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Ekaterina I
authors.initials: EI
authors.lastname: Mokhonova
authors.forename: Vladislav V
authors.initials: VV
authors.lastname: Mokhonov
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Akama
authors.forename: Taiji
authors.initials: T
authors.lastname: Nakae
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D018432:Drug Resistance, Multiple; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C402263:OprM protein, Pseudomonas aeruginosa