Assembly of a Functional Immunoglobulin F v Fragment in Escherichia coli

• DOI: 10.1126/science.3285470
• Publication Date: 2006-10-05T17:21:15Z
• Authors: Arne Skerra; Andreas Plückthun
• Keywords: Phosphorylcholine; Fragment (logic); Protein Engineering

An expression system was developed that allows the production of a completely functional antigen-binding fragment an antibody in Escherichia coli . The variable domains phosphorylcholine-binding McPC603 were secreted together into periplasmic space, where protein folding as well heterodimer association occurred correctly. Thus, assembly pathway for F v E. is similar to whole eukaryotic cell. purified homogeneity with antigen-affinity column single step. correct processing both signal sequences confirmed by amino-terminal sequencing. functionality recombinant demonstrated equilibrium dialysis. These experiments showed affinity constant identical native McPC603, there one binding site phosphorylcholine fragment, and no inactive preparation. This should facilitate future engineering on antibodies.