title: Optimized expression of full-length IgG1 antibody in a common E. coli strain.
abstract: Multi-polypeptide proteins such as antibodies are difficult to express in prokaryotic systems such as E. coli due to the complexity of protein folding plus secretion. Thus far, proprietary strains or fermenter cultures have been required for appreciable yields. Previous studies have shown that expression of heterologous proteins in E. coli can be enhanced by the reduction of protein translation rates. In this paper, we demonstrate that useful quantities of full-length IgG can be expressed and purified from the common E. coli laboratory strain HB2151 in standard shaking culture using a simple strategy of reduced inducer concentration combined with delayed induction times to modulate translation rates. Purified IgG had only marginally reduced avidity compared to mammalian derived IgG. This indicates that this technique can be used to derive antibodies of potentially equal utility as those expressed in mammalian cell culture, particularly for applications where effector functions mediated by the glycosylated residues in the Fragment Crystallizable (Fc) portion of the immunoglobulin are not required.
authors.affiliation: Medical Countermeasures Biological Laboratory, Defense Medical and Environmental Research Institute, DSO National Laboratories, Singapore.
authors.forename: Conrad En Zuo
authors.initials: CE
authors.lastname: Chan
authors.forename: Angeline Pei Chiew
authors.initials: AP
authors.lastname: Lim
authors.forename: Annie Hoi Yi
authors.initials: AH
authors.lastname: Chan
authors.forename: Paul A
authors.initials: PA
authors.lastname: MacAry
authors.forename: Brendon John
authors.initials: BJ
authors.lastname: Hanson
mesh_terms: D000906:Antibodies; D000915:Antibody Affinity; D003001:Cloning, Molecular / Q000379:methods*; D004926:Escherichia coli / Q000235:genetics*; D007074:Immunoglobulin G / Q000096:biosynthesis*; D007700:Kinetics; D008722:Methods
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G